CA1110374A - Compositions containing hydrogenated block copolymers and engineering thermoplastic resins - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

A composition containing a partially hydrogenated block copolymer comprising at least two terminal polymer blocks of a monoalkenyl arene, and at least one intermediate polymer block of a conjugated diene, in an amount of 4 to 40 parts by weight; a polyamide and 5 to 48 parts by weight of a dissimilar engineering plastic, in which the weight ratio of the polyamide to the engineering thermoplastic resin is greater than 1:1, thereby forming a poly blend wherein at least two of the polymers form at least partial continuous interlocked networks with each other. This interlocked structure results in a dimensionally stable poly blend that will not delaminate upon extrusion and subsequent use.

Description

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The invention relates to a composition containing a partially hydrogenated block copolymer comprising at least two terminal polymer blocks A of a monoalkenyl arene having an average molecular weight of from 5,000 to 125,000 and at least one intermediate polymer block B of a conjugated diene having an average molecular weight of from 10,000 to 300,000, in which the terminal polymer blocks A constitute from 8 to 55% by weight of the block copolymer and no more than 25% of the arene double bonds of the polymer blocks A
and at least 80% of the aliphatic double bonds of the polymer blocks B have been reduced by hydrogenation.
Engineering thermoplastic resins are a group of polymers that possess a balance of properties comprising strength, stiffness, impact resistance, and long term dimensional stability that make them useful as structural materials.
Engineering thermoplastic resins are especially attractive ~` as replacements for metals because of the reduction in weight that can often be achieved as, for example, in automotive applications.
~;~ 20 For a particular application, a single thermoplastic ; resin may not offer the combination of properties desired ; and, therefore, means to correct this deficiency are of interest. One particularly appealing route is through ~r ` blending together two or more polymers (which individually have the properties sought) to give a material with the desired combination of properties. This approach has been , "~, .

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successful in :Linl;tod cases, such as in the improvement of irnpact resistance L'or thermoplastic resins, e.g., polystyrene, polypropylene and poly(vinyl chloride), using special b]ending procedures or additives for this purpose. However, in general, blending of thermoplastic resins has not been a sueeessful route to enable one to eombine into a single material the desirable individual eharacteristics of two or more polymers. Instead, it has often been found that such blending results in~'combining the worst features of' eaeh with the result being a material of sueh poor properties as not to be of any praetieal or eommereial value. The reasons for this failure are rather well understood and stem in part from the faet that thermodynamies teaehes that most eombinations of poly~ler pairs are not miscible, although a number of ~ ;~
notable exceptions are known~ More importantly, most polymers adhere poorly to one another. As a result, the interf'aces between component domains (a result of their , . ~
immiscibility) represent areas of severe weakness in blends and, therefore, provide natural flaws and cracks whieh result in faclle meehanieal failure. Beeause of this, '~ most polymer pairs are said to be "incompatible". In some instances the term eompatibility is used synonymously with miseibility, however, compatibility is used here in a more general way that deseribes the ability to eombine two polyrners together for benefieial results and may or may not eonnote miseibility.

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One method wh:icll may be used to circumvent this problem in polymer blends is to "compatibilize" the two polymers by blending in a third component, often referred to as a "compatibilizing agent", that possesses a dual solubility nature for the two polymers to be blended.
Examples of this third component are obtained in block ~ -or graft copolymers. As a result of this characteristic, this agent locates at the interface between components ; and greatly improves interphase adhesion and thér~fore increases stability to gross phase separation.
The invention covers a means to stabilize multi-polymer blends that is independent of the prior art ~ ;
compatibilizing process and is not restricted to the necessity for restrictive dual solubility characteristics.
The materials used for this purpose are special block co-polymers capable oP thermally reversible self-cross-linking.
~ Their action in the present invention is not that visualized ^i~ by the usual compatibilizing concept as evidenced by the general ability of these materials to per~orm similarly for a wide range of blend components which do not conform to the solubility requirements of the previous concept.
- Now, the invention provides a composition containing a partially hydrogenated block copolymer comprising at least two terminal polymer blocks A of a monoalkenyl arene having an average molecular weight of from 5,000 to 125,000, and at least one intermediate polymer block B of a con~ -~ .
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jugated diene having an average molecular weight of from 10,000 to 300,000, ~.
in which the terminal polymer blocks A constitute from 8 to 55% by weight of the block copolymer and no more than 25% of the arene double bonds o:E the polymer blocks A and at least 80% of the aliphatic double bonds of the polymer blocks B have been reduced by hydrogenation, which composition is characterized in that the composition comprises:
(a) 4 to 40 parts by weight of the partially hydrogenated block copolymer;
(b) a polyamide having a number average molecular weight in excess of ~ :~
10,000, (c) 5 to 48 parts by weight of at least one dissimilar engineering thermo-plastic resin being selected from the group consisting of polyolefins, thermolplastic polyesters, thermoplastic cellulosic esters, poly ~`
(arylethers), poly(aryl sulphones)~ polycarbonates, acetal resins, thermoplastic polyurethanes, halogenated thermoplastics, and nitrile :~
~ resins, :~ in which the weight ratio of the polyamide to the dissimilar engineering thermoplastic resin is greater than 1:1 so as to form a polyblend wherein at . ~
least two oE the polymers form at least partial continuous interlocked net- ~ :works with each other.
The block copolymer of the invention effectively acts as a ~:
mechanical or structural stabili~er which interlocks .~ .'.

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the various polymer structure networks and prevents the consequent separaticn of the po]ymers during processing and their subsequent use. As defined more fully herein-after, the resulting structure o~ the polyblend (short for "polymer blend'l) is that of at least two partial continuous interlocking networks. This interlocked structure results in a dimensionally stable polyblend that will not delaminate upon extrusion and subsequent use. :
To produce stable blends it is necessary that at ;~ least two of the polymers have at least partial continuous networks which interlock with each other. Preferably, the block copolymer and at least one other polymer have partial continuous interlocking network structures. In an ideal situation all of the polymers would have complete con-tinuous networks which interlock with each other. A ;
partial continuous network means that a portion of the polymer has a continuous network phase structure while the other portion has a disperse phase structure. Prefer-ably, a major proportion (greater than 50% by weight) of the partial continuous network is continuous. As can be readily seen, a large variety of blend structures is .
possible since the structure of the polymer in the blend may be completely continuous, completely disperse, or partially continuous and partially disperse. Further yet, ;-~
the disperse phase of one polymer may be dispersed in a ,' . ~.
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second polymer and not in a third polymer. To illustrate some of the structures, the following lists the various combinations of polymer structures possible where all structures are complete as opposed to partial structures.
Three polymers (A, B and C) are involved. The subscript "c" signifies a continuous structure while the subscript ; "d" signifies a disperse structure. Thus, the designation ''ACB'' means that p~ymer A is continuous with polymer B, and the designation "BdC" means that polymer B is disperse ;~ 10 in polymer C, etc.

: c AcC BCC , ,.
d AcC BcC
. ACB AcC BdC
d AcC BCC
BdC AcB ACC
C A AcB ACC
,, CdB AcB ACC :, Through practice of the invention~ it is possible to ,~, prepare polyblends that possess a much improved balance of ~ 20 properties as compared to the individual properties of the --~ separate polymers. For example, the invention permits the -~ blending of a large amount of a polyamide with a smaller - amount of a more expensive engineering thermoplastic resin, such as poly(butylene terephthalate), resulting in a polymer blend that retains much of the desirable properties of the more expensive engineering thermoplastic resins at a fraction of the cost.

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It is particularly surprising that even just small amounts of the block copolymer are sufficient to stabilize the structure of the polymer blend over very wide relative concentrations. ~or example, as little as four parts by weight of the block copolymer is suf`ficient to stabilize a blend of 5 to 90 parts by weight polyamide with 90 to 5 parts by weight of a dissimilar engineering thermoplastic.
In addition, it is also surprising that the block co-polymers are useful in stabilizing polymers of such a wide variety and chemical make-up. As explained more fully hereinafter, the block copolymers have this ability to stabilize a wide variety of polymer over a wide range of ~ concentrations since they are oxidatively stable, possess '.''! essentially an infinite viscosity at zero shear stress, and retain network or domain structure in the melt. -~
; Another significant aspect of the invention is that the ease of processing and forming the various polyblends . ' .
`~ is greatly improved by employing the block copolymers as ~;
; stabilizers.
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The block copolymers employed in the composltion according to the invention may have a variety of geometrical -~ structure, since the invention does not depend on any ~ `~
-~ specific geometrical structure, but rather upon the chemical constitution of each of the polymer blocks. Thus, -the block copolymers may be linear, radial or branched.
Methods for the preparation of such polymers are known in .: . .. ..

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the art. The structurc of the polymers 3 S determined by ~;
their metllods Or Ijo.Lymori~cltion. I~lor oxample, li.near polymers result by sequential introduction of the desired monomers into the reaction vessel when using such initiators as lithium-alkyls or dilithio-stilbene, or by coupling a two-segment block copolymer with a difunctional coupling agent. Branched structures,on the - other hand, may be obtained by the use of suitable ..
i coupling agents having a functionality with respec.k to the precursor polymers of three or more. Coupling may be effected with multifunctional coupling agents, such as -~ dihaloalkanes or -alkenes and divinyl benzene as well as certain polar compounds, such as silicon halides~ siloxanes or esters of monohydric alcohols with carboxylic acids.
` 15 The presence of any coupling residues in the polymer may be ignored for an adequate description of the polymers forming a part of the compositions of this invention.
Likewise, in the generic sense, the specific structures also may be ignored. The invention applies especially ~ 20 to the use of selectively hydrogenated polymers having ;:'f~ the~con~iguration before hydrogenation of the following : typlcal species~
~ polystyrene-polybutadiene-polystyrene (SBS) :- polystyrene-polyisoprene-polystyrene (SIS) ;~ 25 poly(alpha-methylstyrene)polybutadiene-poly(alpha-methylstyrene) and ' ~ ~

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poly(alpha-methylstyrenc)polyisoprene-poly(alpha-methylstyrene).
Both polymer blocks A and B may be either homopolymer or random copolymer blocks as long as each polymer block predominates in at least one class o~ the monomers charac-terizing the polymer blocks. The polymer block A may comprise homopolymers of' a monoalkenyl arene and co-~' polymers Or a monoalkenyl arene with a conjugated diene as long as the polymer blocks A individually pred-ominate`'' ,~
~` 10 in monoalkenyl arene units. The term "monoalkenyl arene"
'.' will be taken to include especially skyrene and its ' .~ analogues and homologues including alpha-methylstyrene and ring-substituted styrenes, particularly ring-methyl-ated styrenes. The preferred monoalkenyl arenes are '~
~s' 15 styrene and alpha-methylstyrene, and styrene is --~ particularly pre~erred. The polymer blocks B may comprise ' homopolymers of a conjugated diene, such as butadiene or isoprene, and copolymers of a conjugated diene with a i monoalkenyl arene as long as the polymer blocks B pre-dominate in conjugated diene uni~s. When the monomer employed is butadiene, it is preferred that between 35 and 55 mol. per cent of the condensed butadiene units in the butadiene polymer block have 1,2-conriguration. Thus, when such a block is hydrogenated~ the resulting product is, or resembles, a regular copolymer block of ethylene and butene-1 (EB). I~ the conjugated diene employed is isoprene, the resulting hydrogenated product is or resembles a regular copolymer block of ethylene and propylene (EP).
Hydrogenation of the precursor block copolymers is preferably effected by use of a catalyst comprising the reaction products of an aluminium alky.l compound with nickel or cobalt carboxylates or alkoxides under such ~ ;
- conditions as to substantially completely hydrogenate at least 80% of the aliphatic double bonds, while hydrogenating no more than 25% of the alkenyl arene aromatic double bonds. Preferred block copolymers are those where at least 99% of the aliphàtic double bonds are hydrogenated while less than 5% of the aromatic .
double bonds are hydrogenated.
The average molecular weights of the individual blocks may vary within certain limits. The block co-polymer present in the composition according to the invention has at least two terminal polymer blocks A of a monoalkenyl arene having a number average molecular weight of f~om 5,000 to 125,000, preferably from 7,000 to 60,000, and at least one intermediate polymer block B
of a conjugated diene having a number average molecular weight of from 10,000 to 300,000, preferably from 30,000 to 150,000. These molecular weights are most accurately ;
determined by tritium counting methods or osmotic pressure measurements.

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The proportion of the polymer blocks A of the mono-alkenyl arene should be between 8 and 55% by weight of the block copolymer, preferably between 10 and 30% by weight.
~y polyamide is meant a condensation product whlch contains recurring aromatic and/or aliphatic amide groups ~ ~;
as integral parts of the main polymer chain, such products being known generically as "nylons". A polyamide may be obtained by polymerizing a mono-aminomonocarboxylic acid or an internal lactam thereof having at least two carbon atoms between the amino and carboxylic acid groups; or by polymerizing substantially equimolar proportions of a diamine which contains at least two carbon atoms between -. ' , .
the amino groups and a dicarboxylic acid; or by polymer-! izing a mono-aminocarboxylic acid or an internal lactam ~-thereof as defined above together with substantially equi-molar proportions of a diamine and a dicarboxylic acid.
.
The dicarboxylic acid may be used in the form of a ~unctional derivative thereof, for example an ester.
The term "substantially equimolecular proportions"
(of the diamine and of the dicarboxylic acid~ is used to cover both strict equimolecular proportions and the slight departures therefrom which are involved in conventional ~

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techniques for stabilizing the viscosity Or the resultant polyamides ~ As examples of the said mono~aminomonocarboxylic acids ; or lactams thereof there may be mentioned those compounds ~ ;
containing from 2 to 16 carbon atoms between the amino and carboxylic acid groups, said carbon atoms forming a ring with the -- CO.NH - group in the case of a lactam. As particular examples of aminocarboxylic acids and lactams there may be mentioned ~-aminocaproic acid, buty'rolactam,`'' pivalolactam, caprolactam, capryl-lactam, enantholactam, - ~ .
undecanolactam, dodecanolactam and 3- and 4-amino benzoic acids.
Examples of the said diamines are diamines of the general formula H2N(CH2)nNH2, wherein n is an integer o~ -from 2 to 16, such as trimethylenediamine, tetramethylene-diamine, pentamethylenediamine, octamethylenediamine, decamethylenediamine~ dodecamethylenediamine, hexadeca-methylenediamine, and especially hexamethylenediamine.
C-alkylated diamines, e.g., 2,2-dimethylpentamethylene-diamine and 2~2,4-and 2, Ll, 4-trimethylhexamethylenediamine are further examples. Other diamines which may be mentioned as examples are aromatic diamines, e.g., p-pheny]ene-diamine, 4,4'-diaminodiphenyl sulphone, 4,4'-diaminodi-phenyl ether and 4,4'-diaminodiphenyl sulphone, 4,4'-di-aminodiphenyl ether and 4,4'-diaminodiphenylmethane; and cycloaliphatic diamines, for example diaminodicyclohexyl-methane.

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3~4 The said dicarboxylic acids may be aromatic, for ~;
example isophthalic and terephthalic acids. Preferred dicarboxylic acids are of the formula HOOC.Y.COOH, wherein Y represents a divalent aliphatic radical containing at least 2 carbon atoms, and examples of such acids are sebacic acid, octadecanedioicacid, ;
suberic acid, azelaic acid, undecanedioic acid, glutaric acid, pimelic acid, and especially adipic acid. Oxalic acid is also a preferred acid.
Specifically the following polyamides may be in-corporated in the thermoplastic polymer blends of the inventîon:
polyhexamethylene adipamide (nylon 6:6) polypyrrolidone (nylon 4) polycaprolactam (nylon 6) polyheptolactam (nylon 7) polycapryllactam (nylon 8) polynonanolactam (nylon 9) polyundecanolactam (nylon 11) polydodecanolactam (nylon 12) ~ polyhexamethylene azelaiamide (nylon 6:9) - polyhexamethylene sebacamide (nylon 6:10) polyhexamethylene isophthalamide (nylon 6:iP) polymetaxylylene~ipamide (nylon MXD:6) polyamide of hexamethylene diamine and n-dodecanedioic acid (nylon 6:12) -15- 3L`~ 3~7~

; polyamide of dodecamethylenediamine and n-dodecanedioic acid (nylon 12:12).
Nylon copolymers may also be used~ for example co~
polymers of the following:
hexamethylene adipamide/caprolactam (nylon 6:6/6) hexamethylene adipamide/hexamethylene-isophthalamide (nylon 6:6/6ip) hexamethylene adipamide/hexamethylene-terephthalamide (nylon 6:6/6T) , . .................. .
trimethylhexamethylene oxamide/hexamethylene oxamide (nylon trimethyl 6:2/6:2) hexamethylene adipamide/hexamethylene-azelaiamide (nylon 6:6/6:9) hexamethylene adipamide/hexamethylene~azelaiamide/
caprolactam (nylon 6:6/6:9/6). `
Also useful is nylon 6:3. This polyamide is the product of the dimethyl ester of terephthalic acid and a mixture of isomeric trimethyl hexamethylenediamine.
Preferred nylons ~nclude nylon 6,6/6, 11, 12, 6/3 and 6/12.
The number average molecular weights of the polyamides should be above 10,000.
The term "dissimilar engineering thermoplastic resin"
refers to engineering thermoplastic resins different from those encompassed by the polyamides present in the com-positions according to the invention.

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The term "engineering thermoplastic resin" encompasses ~
the various polymers found in the classes listed in Table A :
below and thereafter defined in the specification.

: TABLE A

1. Polyolefins 2. Thermoplastic polyesters : 3. Poly(aryl ethers) and poly(aryl sulphones)

4. Polycarbonates

5. Acetal resins

6. Thermoplastic polyurethanes

7. Halogenated thermoplastics

8. Nitrile resins Preferably, these engineering thermoplastic resins have glass transition temperatures or apparent crystalline melting points (defined as that temperature at which the :
modulus, at low stress, shows a catastrophic drop) o~ :
over 120C, preferably between 150C ~d 350C, and are capable of forming a continuous network structure through ~ ~ :
a thermally reversible cross-linklng mechanism. Such thermally reversible cross-linking mechanisms include crystallites, polar aggregations, ionic aggregations, : lamellae, or hydrogen bonding. ln a specific embodiment, -where the viscosity of the block copolymer or blended :~
block copolymer composition at processing temperature Tp `~
and a shear rate of 100 s 1 is n, the ratio of the viscosity of the engineering thermoplastic resins, or ;, 37~
blend of engineering therrnoplastic resin with viscosity modifiers to ~ may be between 0.2 and 4.o, preferably o.8 and 1.2. As used in the specification and claims, the viscosity of the block copolymer, polyamide and the thermoplastic engineering resin is the "me]t viscosity"
obtained by employing a piston-driven capillary melt rheometer at constant shear rate and at some consistent temperature above melting, say 260C. The upper limit (350C) on apparent crystalline melting point or glass transit~n temperature is set so that the resin may be processed in low to medium shear rate equipment at com-mercial temperature levels of 350C or less. -The engineering thermoplastic resin includes also blends of various engineering thermoplastic resins and blends with additional viscosity modifying resins.
These various classes of engineering thermoplastics are defined below.
The polyolefins present in the compositions according to the invention are crystalline or crystallizable. ~hey may be homopolymers or copolymers and may be derived from an alpha-olefin or l-olefin having 2 to 5 carbon atoms.
Examples of particular useful polyolefins include low- ;
density polyethylene, high-density polyethylene, iso-tactic polypropylene, poly(l-butene), poly(4-methyl-1-pentene), and copolymers of 4-methyl-1-pentene with linear or branched alpha-olefins. A crystalline or :

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crystallizable structure is important in order for the polymer to be capable of forming a continuous structure with the other polymers in the polymer blend according ::
to the invention. The number average molecular weight of the polyolefins is preferably above 10,000, more prefer-ably above 50,000. In addition, it is preferred that the apparent crystalline melting point is above 100C, prefer-ably between 100C and 250C, and more preferably between 140C and 250C! The preparation of these various poly- ~-olefins are well known. See generally "Olefin Polymers", Volume 14, Kirk-Othmer Encyclopedia of Chemical Technology, pages 217-335 (1967). .
When a high density polyethylene is employed, it has an approximate crystallinity of over 75% and a density in "/
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kilograms per litre (kg/l) of between 0.94 and 1.0 while when a low density polyethylene is employed, it has an approximate crystallinity of over 35% and a density of between 0.90 kg/1 and 0.94 kg/l. The composition ac-cording to the invention may contain a polyethylene havinga number average molecular weight of 50,000 to 500~000.
When a polypropylene is employed, it is the so- -called isotactic polypropylene as opposed to atactic polypropylene. The number average molecular weight-of thë
10polypropylene employed is in excess of 100,000. The poly-propylene may be prepared using methods of the prior art. Depending on the specific catalyst and polymer-ization conditions employed, the polymer produced may contain atactic as well as isotactic~ syndiotactic or so-called stereo-block molecules. These may be separated by selective solvent extraction to yield products of low atactic content that crystallize rnore completely.
The preferred commercial polypropylenes are generally .
;~;prepared using a solid, crystalline, hydrocarbon-in-soluble catalyst made from a titanium trichloride com-;position and an alumini~m alkyl compound, e.g., tri-ethyl aluminium or diethyl aluminium chloride. If . ~
desired, the polypropylene employed is a copolymer -containing minor (1 to 20 per cent by weight) amounts of ethylene or another alpha-olefin as comonomer.

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-20 ~ 374 The poly(l-butene) preferably has an isotactic structure.
The catalysts used in preparing the poly(l-butene) are preferably organo-metallic compounds commonly referred to as Ziegler-Natta catalysts. A typical catalyst is the interacted product resulting from mixing equimolar quan-tities of titanium tetrachloride and triethylaluminium.
The manufacturing process is normally carried out in an inert diluent such as hexane. Manufacturing operations, ; in all phases of polymer formation, are conducted in such a manner as to guarantee rigorous exclusion of water even ` in trace amounts.
One very suitable polyolefin is poly(4-mekhyl-1-pentene). -Poly(4-methyl-1-pentene) has an apparerlt crystalline melt-ing point of between 240 and 250C and a relative density of between 0.80 and 0.85. Monomeric 4-methyl-1-pentene is commercially manufactured by the alkali~metal catalyzed dimerization of propylene. The homopolymerization of 4-methyl-1-pentene with Ziegler-Natta catalysts is described in the Kirk-Othmer Enclopedia of Chemical Technology, Supplement volume, pages 789-792 (second edition, 1~71).
However, the isotactic homopolymer of 4-methyl-1-pentenè
has certain technical defects, such as brittleness and -inadequate transparency. Therefore, commercially available poly(4-methyl-1-pentene) is actually a copolymer with minor proportions of other alpha-olefins, together with the addition of suitable oxidation and melt stabilizer ~.

3~74 :
systems. These copolymers are described in the Xirk-Othmer Encyclopedia of Chemical Technology, Supplement volume, pages 792-907 (second edition, 1971), and are available under the trade name TPX ~ resin. Typical alpha-olefins are linear alpha-olefins having from ~ 4 to 18 carbon atoms. Suitable resins are copolymers ; of 4-methyl-1-pentene with from 0.5 to 30% by weight of a linear alpha-olefin. ;
If desired, the polyolefin is a mixture of various polyolefins. However, the much preferred polyolefin is ~
` isotactic polypropylene. ` ~;
The thermoplastic polyesters, if present in the com-positions according to the invention, have a generally crystalline structure, a melting point over 120C, and ;
are thermoplastic as opposed to thermosetting.

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One particularly userul ~roup of polyesters are those ~- thermoplastic polyesters prepared by condensing a di-;
carboxylic acid or the lower alkyl ester, acid halide, or anhydride derivatives thereof with a glycol, according to methods well known in the art.
-~ Among the aromatic and aliphatic dicarboxylic aeids - suitable for preparing polyesters are oxalic acid, malonie aeid, sueeinie acid, glutaric acid, adipic acid, suberic aeid, azelaic acid, sebaeie acid, terephthalic acid, iso- ~
phthalic acid, p-carboxyphenoacetie acid, p,p'~icarboxydiphenyl, ;;
p,p'-diearboxydiphenylsulphone, p-carboxyphenoxyacetic aeid, p-earboxyphe~oxypropionic acid, p-carboxyphenoxybutyrie acid, p~carboxyphenoxyvaleric aeid, p-earboxyphenoxyhexanoic aeid, p,p'-diearboxydiphenylmethane, p,p diearboxydiphenylpropane, -p,p'-diearboxydiphenyloctane, 3-alkyl-4~ earboxyethoxy)~
benzoic aeid, 2,6-naphthalene diearboxylie aeid, and 2,7-naphthalene dicarboxylic acid. Mixtures of dicarboxylie acids can also be employed. Terephthalie acid is particularly preferred. -~he glyeols suitable for preparing the polyesters include straight-chain alkylene glyco:ls of 2 to 12 earbon atoms, sueh as ethylene glycol, 1,3-propylene glycol, 1,6-hexylene glycol, 1,10-decamethylene glycol, and 1,12-dodecamethylene glycol. Aromatic glyeols can be substituted in whole or in part. Suitable aromatic dihydroxy compounds inelude p-xylylene glyeol, pyroeateehol, resoreinol, :. : ;~, .i ; -23- ~ 3~74 hydroquinone, or alkyl-substituted derivatives of these compounds. Another suitable glycol is 1,4-cyclohexane dimethanol. Much preferred glycols are ~e straight-chain alkylene glycols having 2 to 4 carbon atoms.
:
A preferred group of polyesters are poly(ethylene ; terephthalate), poly(propylene terephthalate), and poly-(butylene terephthalate). A much preferred polyester is poly(bukylene terephthalate). Poly(butylene terephthalate), a crystalline copolymer3 may be formed by the polycondensation of 1,4-butanediol and dimethyl terephthalake or terephthalic acid, and has the generalized formula: ;

n where n varies from 70 to 140. The average molecular weight cf the poly(butylene terephthalake) preferably varies from 20,000 to 25,000. ~`
Commercially available poly(butylene terephthalate) is ayailable under the trade name VALOX ~ thermoplastic polyester. Other commercial polymers include CELANEX
TENITE ~ and VITUF ~ .
Other useful polyesters include the cellulosic esters.
; The thermoplastic cellulosic esters employed herein are widely used as moulding, coating and film-forming materials .
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, , and are well known. These materials include the solid thermoplas-tic forms of cellulose nitrate, cellulose acetate (e.~., cellulose diacetate, cellulose tri-acetate), cellulose butyrate, cellulose acetate butyrate, cellulose propionate, cellulose tridecanoate~ carboxy-methyl cellulose, ethyl cellulose~ hydroxyethyl cellulose and acetylated hydroxyethyl cellulose as described on pages 25-28 of ~odern Plastics Encyclopedia, 1971-72, and references listed therein. -Another useful polyester is a polypivalolactone. Poly- -pivalolactone is a linear polymer having recurring ester ;
structural units mainly of the formula:
- CH2--C~CH3)2 - C(O)O
i.e., units derived from pivalolactone. Preferably, the poly-ester is a pivalolactone homopolymer. Also included, however, are the copolymers of pivalolactone with no more than 50 mol.%, preferably not more than 10 mol.% of another beta-propio-lactone, such as beta-propiolactone, alpha,alpha-diethyl-beta-propiolactone and alpha-methyl-alpha-ethyl-beta-propio-lactone. The term "beta-propiolactones" refers to beta- ~
propiolactone (2-oxetanone) and to derivatives thereof which ~;
carry no substituents at the beta-carbon atom of the lactone ring. Preferred beta-propiolactones are those containing a tertiary or quaternary carbon atom in the alpha-position relative to the carbonyl group. Especially preferred are the alpha,alpha-dialkyl-beta-propiolactones wherein each of the alkyl groups lndependently has from one to four carbon atoms.
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Examples of useful monomers are:
alpha-ethy]-alpha-methyl-beta-propiolactone, alpha-methyl-alpha-isopropyl-beta-propiolactone, alpha-ethyl-alpha-n-butyl-beta-propiolactone, alpha-chloromethyl-alpha-methyl-beta-propio].actone, alpha,alpha-bis(chloromethyl)-beta-propiolactone, and alpha,alpha~dimethyl-beta-propiolactone (pivalolactone).
These polypivalolactones have an average molecular weight in excess of 20,000 and a melting point in excess of 120C.
Another useful polyester is a polycaprolactone.
Preferred poly(~-caprolactones) are substantially linear polymers in which the repeating unit is: ~;
r 0 t CH2 CH2 CH2 CH2 CH2 c _ These polymers have similar properties to the polypivalo-lactones and may be prepared by a similar polymerization mechanism.
Various polyaryl polyethers are also useful as engineer-ing thermoplastic resins. The poly(aryl polyethers) which may be present in the composition according to the invention include the linear thermoplastic polymers composed of re-curring units having the formula:

(0 G 0 - G') - I

wherein Gisthe residuum of a dihydric phenol selected from the group consisting o~:

' ' .

, ~, '"' ', ' ' _ ~ II

~ ~' and - ::

- ~ -R

;
wherein R represents a bond between aromatic carbon atoms~
- O , S , - s-s-,or a divalent hydrocarbon radical : ~ .
having from 1 to 18 carbon atoms inclusive, and G' is the ~ :
residuum of a dibromo or di-iodobenzenoid compound selected from the group consisting of: ..

/ ~ - IV

and - R' = V ~ ~
:' whereln R' represents a bond between aromatic carbon atoms, ~: -. - O ~ S- - , - S- S - ,:or a divalent hydrocarbon ; 10 radical having from 1 to 18 carhon atoms inclusive, with ~:~ the provisions that when R is - O , R' is other than O ; when R' is - O , R is other than - O
when G is II, G' is V, and when G' is IV, G is III.
., ~
: ' j ,; ~
, , "

. , ~ ,. ~ , , . ;
, , ,, ~ , . , .: ::

-27~ 37~

Polyarylene polyethers of this type exh;bit excellent physical properties as well as excellent thermal oxidative and chemical stability. Commercial poly(aryl polyethers) are available under the trade name ARYLON T ~ Polyaryl ethers, having a melt temperature of between 280C and 310C.
Another group of useful engineering thermoplastic resins include aromatic poly(sulphones) comprising re-peating units of the formula:
...
Ar S02 -:~ in which Ar is a bivalent aromatic radical and may vary from unit to unit in the polDmer chain (so as to form co-polymers of various kinds). Thermoplastic poly(sulphones) generally have at least some units of the structure:
~ i ~/X~
, ,...... ' SO2 in which Z is oxygen or sulphur or the residue of an aromatic diol, such as a 4,4' bisphenol. One example of such a poly(sulphone) has repeating units of the formula: :

--0~\> SO2 : ~

, , ; , -~ 3~7~ :

another has repeating units of the formula:

~/ 3-S-~3-so2 ~ ~
; and others have repeating units of the formula:

~-SO2 C~ rC~
or copolymerized units in various proportions of the formula:
-SOz- `~
and ~

~ ~--~--SO2--~

The thermoplastic poly~sulphones) may also have repeating units having the formula:

Poly(ether sulphones) having repeating units of the following structure:

' :~ ' ~ ' -29~ 37 4 ~ 2~ ~

and poly(ether sulphones) having repeating units of the fol].owing structure: -so2 ~,~; o~3 c~3~oL
¦ ~ CH~ ~n are also useful as engineering thermoplastic resins.
; The polycarbonates which may be present in the com-:~ 5 positions according to the invention are of the general ~ formulae:
O
: "
(Ar- A-Ar- O- C- O) n : :
and . , (Ar- 0-~ - O) II
:~ n ,;; ,. , . wherein Ar represents a phenylene or an alkyl, alkoxy, :; halogen or nitro-substituted phenylene group; A represents a carbon-to-carbon bond or an alkylidene, cycloalkylidene, :-:
alkylene, cycloalkylene, azo, imino, sulphur, oxygen, sulphoxide or sulphone group, and n is at least two.

~, , , : :

~ 37 4 The preparation o~ the polycarbonates is well known.
A preferred method of preparation is based on the reaction carried out by dissolving the dihydroxy component in a base, such as pyridine and bubbling phosgene into the stirred solution at the desired rate. Tertiary amines may be used to catalyze the reaction as well as to act as acid acceptors throughout the reaction. Since the reaction is normally exothermic, the rate of phosgene addition can be used to control the reaction temperature. The reactions generally utilize equimolar amounts of phosgene and di-hydroxy reactants, however, the molar ratios can be varied dependent upon the reaction condltions. ;~
In the formulae I and II mentioned, Ar and A are, ~ preferably, p-phenylene and isopropylidene, respectively.
- 15 This polycarbonate is prepared by reacting para,para'~so-propylidenediphenol with phosgene and is sold under the ~-trade mark LEXAN(R) and under the trade mark MERLON ~.
This commercial polycarbonate has a molecular weight of around 18,000, and a melt temperature of over 230C.
Other polycarbonates may be prepared by reacting other dihydroxy compounds, or mixtures of dihydroxy compounds, ~ with phosgene. The dihydroxy compounds may include aliphatic - dihydroxy compounds although for best high temperature properties aromatic rings are essential. The dihydroxy ~;
compounds may include within the structure diurethane linkages. Also, part o~ the structure may be replaced by siloxane linkage.

. . .

~ 3 The acetal resins which may be present in the com-positions according to the invention include the high molecular weight polyacetal homopolymers made by polymer-izing formaldehyde or trioxane. These polyacetal homo-polymers are commercially available under the trade nameDELRIN ~. A related polyether-type resin is available under the trade name PENTON ~ and has the structure:

CH2Cl _ -O CHz C CH2-;~ CH2Cl n The acetal resin prepared from formaldehyde has a high molecular weight and a structure typified by the following:

- H- o ( CH2- O- CH2- ) ~ H -x where terminal groups are derived from controlled amounts of water and the x denotes a large (preferably 1500) number of -formaldehyde uni~s linked in head-to-tail fashion. To in-crease thermal and chemical resistance, terminal groups are typically converted to esters or ethers.
Also included in the term polyacetal resins are the polyacetal copolymers. These copolymers include block co-polymers of formaldehyde with monomers or prepolymers of other materials capable of providing active hydrogens, -32~ i37~

such as alkylene glycols, polythio]s, vinyl acetate-acrylic acid copolymers, or reduced butadiene/acrylonitrile polymers.
Celanese has commercially available a copolymer of formaldehyde and ethylene oxide under the trade name CELCON
that is useful in the blends of the present invention. These copolymers typically have a structure comprising recurring units having the formula:

~ :, ~~

wherein each R1 and R2 is selected from the group consisting of hydrogeng lower alkyl and lower halogen substituted ~: .
alkyl radicals and wherein n is an integer from zero to three and wherein n is zero in from 85% to 99.9% of the reourring units.
Formaldehyde and trioxane can be copolymerized with other aldehydes, cyclic ethers, vinyl compounds, ketenes a :. `-.
cyclic carbonates, epoxldes, isocyanates and ethers. These compounds include ethylene oxide, 1,3-dioxolane, 1,3-dioxane, 1,3-dioxepene, epichlorohydrin, propylene oxide, isobutylene oxide, and styrene oxide.

~'.
.

, .

.,. . . ~ , , Polyurethanesg otherwise known as isocyanate resins, also can be employed as engineering thermoplastic resin as long as they are thermoplastic as opposed to thermo-setting. ~or example, polyurethanes formed from toluene di-isocyanate (TDI) or diphenyl methane 4,4-di-isocyanate (MDI) and a wide range of polyols, such as, polyoxyethylene glycol~ polyoxypropylene glycol, hydroxy-terminated poly-esters, polyoxyethylene-oxypropylene glycols are suitable.
These thermoplastic polyurethanes are available under the trade name Q-THANE ~ and under the trade name PELETHANE ~ CPR.
Another group of useful engineering thermoplastics include those halogenated thermoplastics having an essentially crystalline structure and a melt point in excess of 120C. ; .
These halogenated thermoplastics include homopolymers and copolymers derived from tetrafluoroethylene, chlorotrifluoro-ethylene, bromotrifluoroethylene, vinylidene fluoride, and vinylidene chloride.
Polytetrafluoroethylene (PTFE) is the name given to fully fluorinated polymers of the basic chemical formula ( -CF CF ) which contain 76% by weight fluorine.
These polymers are highly crystalline and have a crystalline ~34~ ~ 3 melting point o~ over 300C. Commercial PTFE is available ~ !
under the trade name TEFLON ~ and under the trade name FLUON ~ . Polychlorotrifluoroethylene (PCTFR) and poly-bromotrifluoroethylene (PBTFE) are also available in high molecular weights and can be employed in the present in-vention.
Especially preferred halogenated polymers are homo-polymers and copolymers of vinylidene fluoride. Poly~
(vinylidene fluoride) homopolymers are the partially fluorinated polymers of the chemical formula ( CH2 - CF2 ~ .
These polymers are tough linear polymers with a crystalline melting Point at 170C. Commercial homopolymer is available under the trade name KYNAR ~ The term "poly(vinylidene fluoride)" as used herein refers not only to the normally solid homopolymers of vinylidene fluoride, but also to the normally solid copolymers of vinylidene fluoride containing at least 50 mol.% of polymerized vinylidene fluoride units, preferably at least 70 mol.% vinylidene fluoride and more preferably at least 90 mol.%. Suitable comonomers are , halogenated olefins containing up to 4 carbon atoms, for example~ sym. dichlorodifluoroethylene, vinyl fluoride, vinyl chloride, vinylidene chloride, perfluoropropene,per- ~ `
fluorobutadiene, chlorotrifluoroethylene, trichloroethylene and tetrafluoroethylene.
Another useful group of halogenated thermoplastics include homo~olymers and copolymers derived from vinylidene chloride. Crystalline vinylidene chloride copolymers are ~' .. , .. ,.. ,............... ... , . . . ~

-35- ~ 4~7 ~

especially proLorred. Tlle normally crystalline vinylidene chloride copolymers that are useful in the present in-vention are those containing at least 70% by weight of vinylidene chloride together with 30% or less of a co-polymerizable monoethylenic monomer. Exemplary of suchmonomers are vinyl chloride, vinyl acetate, vinyl propionate, acrylonitrile, alkyl and aralkyl acrylates having alkyl and aralkyl groups of up to about 8 carbon atoms, acrylic acid, acrylamide, vinyl alkyl ethers, vinyl alkyl ketones, acrolein, allyl ethers and othe~s, butadiene and chloropropene. Known ternary compositions also may be employed advantageously. Representative of such polymers are those composed of at least 70% by weight of vinylidene chloride with the remainder made up of, for example, acrolein and vinyl chloride, acrylic acid and acrylonitrile, a]kyl acrylates and a:lkyl methacrylates, acrylonitrile and butadiene, acrylon:itrile and itaconic acid, acrylonitrile and vinyl acetate, vinyl propionate or vinyl chloride, allyl esters or ethers and vinyl chloride, butadiene and vinyl acetate, vinyl propionate, or vinyl chloride and vinyl ethers and vinyl chloride.
Quaternary polymers of similar monomeric composition will also be known. Particularly useful for the purposes ~
the present invention arc copolymers of from 70 to 95% by weight vinylidene chloride with the balance being vinyl chloride. Such copolymers may contain conventional amounts ,'` :

.~ .
. . .

"
. , . . ', 36 1~37~

and types of plasticizers, stabilizers, nucleators and extrusion aids. Further, blends of two or more of such norrnally crystalline vinylidene chloride polymers may be used as well as blends comprising such normally ~
crystalline polymers in combination with other polymeric ;
modifiers, e.g., the copolymers of ethylene-vinyl acetate, ; styrene-maleic anhydride, styrene-acrylonitrile and poly-~ ethylene.
: : ~
The nitrile resins useful as engineering thermoplastic resin are those thermoplastic materials having an alpha,beta- -;
olefinically unsaturated mononitrile content of 50% by weight or greater. These nitrile resins may be homopolymers, copolymers, grafts of copolymers onto a rubbery substrate, ~; or blends of homopolymers and/or copolymers. `
The alpha,beta-olefinically unsaturated mononitriles encompassed herein have the structure CE2 = C - CN
R ;
where R lS hydrogen, an alkyl group having from 1 to 4 carbon atoms, or a halogen. Such compounds include acrylo-nitrile, alpha-bromoacrylonitrile, alpha-fluoroacrylo-20~ nitrlle, methacrylonitrile and ethacrylonitrile. The most preferred olefinically unsaturated nitriles are acrylo-~ nitrile and methacrylonitrile and mixtures thereof.
; These nitrile resins may be divided into several classes on the basis of complexity. The simplest molecular , . I .
.` ;', ,'' ,~

' ' ~" '' ' , : , :

-37~ '3~ 4 structure is a random copolymer, r~redominantly acrylonitrile or methacrylonitrile. The most common example is a styrene-acrylonitrile copolymer. Block copolymers Or acrylonitrile, in which long segments of polyacrylonitrile alternate with segments of polystyrene, or of polymethyl methacrylate, are also known.
Simultaneous polymerization of more than two co-monomers produces an interpolymer, or in the case of three components, a terpolymer. A large number of co- `
monomers are known. These include alpha-olefins of from 2 to 8 carbon atoms, e.g., ethylene, propylene, iso- ~
butylene, butene-1, pentene-1, and their halogen and ~ -aliphatic substituted derivatives as represented by vinyl chloride and vinylidene chloride; monovinylidene aromatic hydrocarbon monomers of the general formula~

` ~1 :, H2C ---C~

wherein R1 is hydrogen, chlorine or methyl and R2 is an aromatic radical of 6 to 10 carbon atoms which may also contain substituents, such as halogen and alkyl groups attached to the aromatic nucleus, e.g., styrene, alpha-methyl styrene, vinyl toluene, alpha-chlorostyrene, ortho-chlorostyrene~ para-chlorostyrene, meta-chlorostyrene, :, ortho-methy] styrene, para-methyl styrene, ethyl styrene, .",~ ~.

:........................................................................ ..
i.~
~i .

:' .
'. ' :: ~

. . .
.: , ,.

isopropyl styrene, dich~ll)rostyrene and vinyl naphthalene.
Especially preferred cc)monomers are isobutylene and styrene.
Another group of comonomers are vinyl ester monomers of the general formula:

H
3 , ; C=O

~ R3 ~ 5 wherein R3 is selected from the group comprising hydrogen, alkyl groups of from 1 to 10 carbon atoms, aryl groups of from 6 ko 10 carbon atoms including the carbon atoms in ring-substituted alkyl substituentsj e.g., vinyl formate, ; vinyl acetate, vinyl propionate and vinyl benzoate.
Similar to the foregoing and also useful are the vinyl ether monomers of the general formula: ~-; 2 wherein RLI is an alkyl group of from 1 to 8 carbon atoms, an aryl group of from 6 to 10 carbons, or a monovalent -~

aliphatic radical of from 2 to 10 carbon atoms, which aliphatic radical may be hydrocarbon or oxygen-containing, e.g., an aliphatic radical with ether linkages9 and may also contain other substituents, such as halogen and carbonyl. Examples of these monomeric vinyl ethers include vinyl methyl ether, vinyl ethyl ether, vinyl n-butyl ether, vinyl 2-chloroethyl ether, vinyl phenyl ether, vinyl isc-., - ':

~' ~
:; ' 39 ~ 374 butyl ether, vinyl cyclohoxyl ether, p-butyl cyelohexyl ether, vinyl ether or p-chlorophenyl glycol.
Other comonomers are those comonomers which contain a mono- or dinitrile function. Examples of these include methylene glutaronitrile, (2,4-dicyanobutene-1)~ vinyl-idene cyanide, crotonitrile, fumarodinitrile, maleodi-nitrile.
Other comonomers inelude the esters of olefinieally unsaturated earboxylie aeids,preferably the lower al~yl esters of alpha,beta-olefinieally unsaturated earboxylie aeids and more preferred the esters having the strueture:

.
wherein Rl is hydrogen, an alkyl group having from 1 to 4 earbon atoms, or a halogen and R2 is an alkyl group having from 1 to 2 earbon atoms. Compounds of this type inelude methyl aerylate, ethyl aerylate, methyl methaerylate, ethyl methacrylate and methyl alpha-chloro acrylate. Most ~-preferred are methyl acrylate, ethyl acrylate~ methyl metha-crylate and ethyl methacrylate.
Another class of nitrile resins are the graft co-polymers which have a polymeric backbone on which branches of another polymeric chain are attached or grafted.
~- Generally the backbone is preformed in a separate reaction.
, ~ Polyacrylonitrile may be grafted with chains of styrene, " ::

' ,:

~4~

viny] acetate, or methyl methacrylate, for example. The backbone may consist of one, two, three, or more com-ponentsa and the grafted branches may be composed of one, two, three or more comonomers.
-~ 5 The most promising products are the nitrile co-polymers that are partially grafted on a preformed rubbery substrate. This substrate contemplates the use ; of a synthetic or natural rubber component such as poly-butadiene, isoprene, neoprene, nitrile rubbers, natural 1~ rubbers, acrylonitrile-butadiene copolymers, ethylene-propylene copolymers, and chlorinated rubbers which are used to strengthen or toughen the polymer. This rubbery component may be incorporated into the nitrile containing polymer by any of the methods which are well known to those skilled in the art, e.g., direct polymerization of monomers, grafting the acrylonitrile monomer mixture onto the rubber backbone or physical admixtures of the rubbery component. Especially preferred are polymer blends derived by mixing a graft copolymer of the acrylonitrile and co-monomer on the rubber backbone with another copolymer of : ~ :
acrylonitrile and the same comonomer. The acrylonitrile-based thermoplastics are frequently polymer blends of a - grafted polymer and an ungrafted homopolymer.

Commercial examples of nitrile resins include ~AREX

210 resin, an acrylonitrile-based high nitrile resin con-~ taining over 65% nitrile, and LOPAC ~ resin containing .: ' ~ ;
.

, -41~ 7~

over 70% nitrile, thr(?e-l`ourt~ls o~ it derived f'rom metha-crylonitrile.
In order to better match the viscosity characteristics of the thermoplastic engineering resin~ the polyamide and the block copolymer, it is sometimes useful to first blend the dissimilar thermoplastic engineering resin with a viscosity modifier bef'ore blending the resulting mixture with the polya~'ide and block copolymer. Suitable viscosity modifiers have a relatively high viscosity, a melt témper- ¦~
ature of over 230 C, and possess a viscosity that is not very sensitive to changes in temperature. Examples of suit- "
able viscosity modifiers include poly(2,6-dimethyl-1,4-phenylene)oxide and blends of poly(2,6-dimethyl-1,4-phenyl-ene)oxide with polystyrene.
The poly(phenylene oxides) included as possible viscosity modifiers may be presented by the following formula: ~ ~
R1 ~ -~ l _ O-;~ L 1 ~m ~

wherein R1 is a monovalent substituent selected from the group consisting Or hydrogen, hydrocarbon radicals ~ree of ' 20 a tertiary alpha-carbon atom, halohydrocarbon radicals "~

:. ~ .

having at least two carbon atoms between the halogen atom and phenol nucleus and being free of a tertlary alpha-carbon atom, hydrocarbonoxy radicals free of aliphatic, tertiary alpha-carbon atoms, and halohydro- -carbonoxy radicals having at least two carbon atoms -between the halogen atom and phenol nucleus and being free of an aliphatic, tertiary alpha-carbon atom, R'1 is the same as R1 and may additionally be a halogen; m is an --integer equal to at least 50, e.g., from 50 to 800 and -~
preferably 150 to 300. IncIuded among these preferred polymers are polymers having a molecular weight in the range of between 6,ooo and 100,000, preferably 40,000.
; Preferably, the poly(phenylene oxide) is poly(2,6-di-methyl-1,4-phenylene)oxide.
; 15 Commercially, the poly(phenylene oxide) is available as a blend with styrene resln. These blends typically comprise between 25 and 50% by weight polystyrene units, ;
and are available from General Electric Company under the ; trade name NORYL ~ thermoplastic resin. The preferred ~20 ~ molecular weight when employing a poly(phenylene oxide)/
polystyrene blend is between 10,000 and 50,000, preferably "~ around 30,000.
The amount of viscosity modifier employed depends primarily upon the difference between the viscosities of 25 the block copolymer and the engineering thermoplastic resin at the temperature-Tp. The amounts may range from O to 100 `
:: :
`

' ~

~: . , , , ., , , ~
,, , ~

_43~ '37~ :

parts by weight viscosity modifier per 100 parts by weight engineering thermoplastic resin, preferably from 10 to 50 parts by weight per 100 parts of engineering thermoplastic resin.
There are at least two methods (other than the absence of delamination) by which the presence of an interlocking network can be shown. In one method, an interlocking net-work is shown when moulded or extruded objects made from the blends of this invention are placed in a refluxing solvent that quantitatively dissolves away the block co-polymer and other soluble components, and the remaining polymer structure (com~rising the thermoplastic engineer-ing resin and polyamide) still has the shape and con-, ;; tinuity of the moulded or extruded object and is intact structurally without any crumbling or delamination, and the refluxing solvent carries no insoluble particulate matter. If these criteria are fulfilled, then both the unextracted and extracted phases a~e interlocking and -continuous. The unextracted phase must be continuous because it is geometrically and mechanically intact.
The extracted phase must have been continuous before , - ~
extraction, since quantitative extraction of a dispersed -i phase from an insoluble matrix is highly unlikely.

` Finallys interlocking networks must be present in order to have simultaneous continuous phases. Also, confirmation -~ of the continuity of the unextracted phase may be ~-,'. ,' ,;. .
:' , .

44 ~ qh~3~ ~

confirmed by microscopic examination. In the present blends containing more than two components, the interlocking nature and continuity of each separate phase may be established by selective extraction. For example, in a blend containing block copolymer, polypropylene and nylon 6, -the block copolymers may be first extracted by refluxing toluene, leaving the polypropylene and nylon phases. Then the nylon may be extracted by hydrochloric acid leaving the polypropylene phase. Alternatively, the nylon may be extracted first and then the block copolymer. Phase continuity and the interconnecting of holes may be microscopically examined -after each extraction.
In the second method, a meehanical property such as tensile modulus is measured and compared with that expected ~- ~
from an assumed system where each continuous iso- ;
tropically distributed phase contributes a fraction of -~/
;` . : .
~ the mechanical response, proportional to its compositional , . ~ . .
fraction by volume. Correspondence o~ the two values indicates presence of the interlocking network, whereas, if the interlocking network is not present, the measured value is different than that of the predicted value.
',:' An important aspect of the present invention is that the relative proportions of the various polymers in the blend can be varied over a wide range. The relative proportions ofthe polymers are presented below in parts - by weight (the total blend comprising 100 parts):
, -45- ~ 37 ~

Parts Preferred by weight parts by _ weight Dissimilar engineering thermoplastic resin 5 to 48 10 to 35 5Block copolymer 4 to 40 8 to 20 The polyamide is present in an amount greater than the amount of the dissimilar engineering thermoplastic, i.e., the weight ratio of polyamide to dissimilar engineer-ing thermoplastic is greater than 1:1. Accordingly, the amount of polyamide may vary from 30 parts by weight to 91 parts by weight, preferably from 48 to 70 parts by weight. Note that the minimum amount of block copolymer necessary to achieve these blends may vary with the ~- particular engineering thermoplastic.
;~ 15 The dissimilar engineerlng thermoplastic resin, polyamide and the block copolymer may be blended in any ,''''3'~manner that produces the interlocking network. For example, the resin, polyamide and block copolymer may be dissolved in a solvent common for all and coagulated by admixing in a solvent in which none of the polymers are soluble. But~ a particularly useful procedure is to intimately mix the polymers in the form of granules and/or ;~
powder in a high shear mixer. "Intimately mixing" means ~ -to mix the polymers with sufficient mechanical shear and thermal energy to ensure that interlocking of the various , ~ 37 4 networks is achieved. Intimate mixing is typically achieved by employing h:igh shear extrusion compounding machines9 such as twin screw compounding extruders and thermoplastic extruders having at least a 20:1 I./D ratio ~; -and a compression ratio of 3 or L~
The mixing or processing temperature (Tp) is selected in accordance with the particular polymers to be blended.
~or example, when melt blending the polymers instead of -solution blendinga it will be necessary to selêct a processing temperature above the melting point of the ~-.
highest melting point polymer. In addition, as explained more fully hereinafter, the processing tempe~ature may -~
also be chosen so as to permit the isoviscous mixing of the polymers. The mixing or processing temperature may be between 150 C and 400C, pre~erably between 230C and 300C.
l Another parameter that is important in melt blending -~ to ensure the rOrmation of interlocklng networks is matching the viscosities of the block copolymer, polyamide and the dissimilar engineering thermoplastic resin (isoviscous ~` mixing) at the temperature and shear stress of the mixing ~` process. The better the interdispersion of the engineering resin and polyamide in the block copolymer network, the better the chance for formation of co-continuous inter-locking networks on subsequent cooling. Therefore, it has been found that when the block copolymer has a viscosity ... . . . .......... ... ... ....... ... . ........... ..... . . . . ..

~374 ~ poise at temperature Tp and shear rate of 100 s 1, it is preferred that the engineering thermoplastic resin and/or the polyamide have such a viscosity at the temper-ature Tp and a shear rate of 100 s 1 that the ratio of the viscosity of the block copolymer divided by the viscosity of the engineering thermoplastic and/or polyamide be between 0.2 and 4.0, preferably between o.8 and 1.2.
Accordinglyg as used herein, isoviscous mixing means that the viscosity of the block copolymer divided by the`
viscosity of the other polymer or polymer blend at the temperature Tp and a shear rate of 100 s 1 is between 0.2 and 4Ø It should also be noted that within an extruder, there isawide distribution of shear rates.
Therefore, isoviscous mixing can occur even though the . . .
` 15 viscosity curves of two polymers differ at some of the shear rates.
In some cases, the order of mixing the polymers is ',! critical. Accordingly~ one may choose to mix the block copolymer with the polyamide or other polymer first, and then mix the resulting blend with the dissimilar engineer-ing thermoplastic, or one may simply mix all the polymers -~
at the same time. There are many variants on the order of mixing that can be employed, resulting in the multi-component blends of the present invention. It is also clear that the order of mixing can be employed in order to better match the relative viscosities of the various polymers.

3~4 The block co~)olymer or block copolymer blend may be selected to essentially match the viscosity of the engineering thermoplastic resin and/or polyamide Optionally~ the block copolymer may be mixed with a rubber compounding oil or supplemental resin as --described hereinafter to change the viscosity charac-teristics of the block copolymer.
The particular physical properties of the block copolymers are important in forming co-continuous~inter-` 10 locking networks. Specifically~ the most preferred block copolymers when unblended do not melt in the ordinary ~-sense with increasing temperature, since the viscosity of these polymers is highly non-Newtonian and tends to increase without limit as zero shear stress is approached.
~urther, the viscosity of these block copolymers is also relatively insensitive to temperature. This rheological behavlour and inherent thermal stability o~ the block co-polymer e~hances its ability to retain its network (domain) structure in the melt so that when the various 2~ blends are made,interlocking and continuous networks are ~ormed.
The viscosity behaviour of the engineering thermoplastic resins, and polyamides on the other hand, is more sensitive to temperature than that of the block copolymers. Ac-cordingly, it is often possible to select a processing ; temperature Tp at which the viscosities of the block ' , li37~

coPolymer and dissimilar engineering resin and/or poly~
amide fall within the required range necessary to form interlocking networks. Optionally, a viscosity modifier, as hereinabove described, may first be blended with the engineering thermoplastic resin or polyamide to achieve the necessary viscosity matching.
The blend of partially hydrogenated block copolymer, ~ ~
polyamide and dissimilar engineering thermoplastic resin -may be compounded with an extending oil ordinarily used`
in the processing of rubber and plastics. Especially preferred are the types of oil that are compatible w1th the elastomeric polymer blocks of the block copolymer.
While oils of higher aromatics content are satisfactory, those petroleum-based white oils having low volatility and less than 50% aromatics content as determined by the clay gel method (tentative ASTM method D 2007) are particularly preferred. The oils preferably have an initial boiling point above 260C.
The amount of oil employed may vary from O to 100 phr (phr = parts by weight per hundred parts by weight of - ;
block copolymer), preferably from 5 to 30 phr.
The blend of partially hydrogenated block copolymer~
polyamide and dissimilar engineering thermoplastic resin may be further compounded with a resin. The additional resin may be a flow promoting resin such as an alpha- ;~
methylstyrene resin and an end-block plasticizing resin.

~ 37 _50_ Suitable end block plasticizing resins include coumarone-indene resins, vinyl toluene-alpha-methylstyrene co~
polymers, polyindene resins and low molecular weight polystyrene resins.
The amount of additional resin may vary from 0 to 100 phr, preferably from 5 to 25 phr.
Further the composition may contain other polymers, fillers, reinforcements, anti-oxidants, stabilizers, fire retardants, anti-blocking agents and other r~bber and plastic compounding ingredients.
Examples of fillers that can be employed are mentioned in the 1971-1972 Modern Plastics Encyclopedia, pages 2L~0-247.
- Reinforcements are also useful in the present polymer blends. A reinforcement may be defined as the material that is added to a resinous matrix to impro~e the strength of the polymer. Most of these reinforcing materials are in- ;
organic or organic products of high molecular weight. -~
Examples of reinforcements are glass fibres, asbestos, boron fibres, carbon and graphite fibres, whiskers, quartz ;
and silica fibres, ceramic fibres, metal fibres, natural ;
organic fibres, and synthetic organic fibres. Especially preferred are reinforced polymer blends containing 2 to 80 per cent by weight of glass fibres, based on the total weight of the resulting reinforced blend.
The polymer blends of the invention can be employed as metal replacements and in those areas where high performance is necessary.

3~7~

In the illustrative Examples and the comparative Example given below, various polymer blends were prepared by mixing the polymers in a 3.125 cm Sterling~ Extruder having a Kenics~ Nozzle.
The extruder has a 24:1 L/D ratio and a 3.8:1 compression ratio screw.
The various materials employed in the blends are listed below:
1) Block copolymer - a selectively hydrogenated block copolymer according to the invention having a structure S-EB-S and block molecular weights of 7,500-38,000-7,500.
2) Oil - TUFFLO~ 6056 rubber extending oil.
3) Nylon 6 - PLASKO ~ 8207 polyamide~
4) Nylon 6-12 - ZYTEL~ 158 polyamide.
5) Polypropylene - an essentially isotactic polypropylene having a melt flow index of 5 (230C/2.16 kg).
6) Poly(butylene terephthalate) ("PBT") - VALO ~ 310 resin.
7) Polycarbonate - MERLO ~ M-40 polycarbonate.
20 8~ Poly(ether sulphone) - 200 P.

9) Polyurethane - PELLETHAN ~ CPR.

10) Polyacetal - DELRI ~ 500.

11) Poly(acrylonitrile-co-styrene) ~ BAREX~ 210.

12) Fluoropolymer - TEFZEL~ 200 poly(vinylidene fluoride) ~-copolymer.

, .

, . .. : ,. . :, - 5 ~ 37~

In all blends containing an oil component, the block copolymer and oil were premixed prior to the addition of the other polymers.
Illustrative Example I
Various polymer blends were prepared according to the present invention. In each case, the polymer blend was easily mixed, and the extrudate was homogeneous in appearance. Further, in each case, the resulting poly~
blend had the deslred continuous, interlocking networks as established by the criteria hereinabove descrlbed.
The compositions, conditions and test results are presented below in Table I. The compositions are listed in percent by weigh~.

.

~ ' ~:
:'~

.~$:~tl!3~7~

~.
,`' :, . .
_ _ ____ _ , ~ ~ ~ oo o o .
~ ~ _ ~ ~ _ ___ __ ___ ~;,','"`' ': ~ : ~ ~ U~ o o : :: , l `~ ~L~
~, :

T OD _ ~ _ ~ er _ _ _ _ r~ ~
~1 ~ a~, Lr~ _ ul ___ _ _ o ~ C N : V : td i ~ ~J O ~ V
- Z O ~9 ~1 O Q Pi Q ~_ ~ ~d ~ o - p ~ h : ~
~ O ~ ~ ~: P~ _ ~ _ ~ ~ _~ S~ X ~0~
~ ~ o æ' ~ ~ o ~ P~ ~ Q P~ ~ O

.. '~ '~
.' ,. .
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o o r.~l I~ r~
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cn O -- O Ir~ N _ ~ _ ._ ~ C _ N _ _ ~ _ _ U~ .

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_ S _ _ l _ - _- O~ ~.
~uo â) o ~ ~rl S~ S
I s,, ~ ~ ~ ul a~
a)a) td ~ ~ O ~ ~ ~ a O r,~J ~1~1~1 1~: S~ t~ ~1 ~1 u~ ~ a) S~
. l ~1 :~~ ~ O a) ~: ~d ~ I ~ ~ :~ ::
O O l ~ ~ ~ Q ~: ~) ~ S~ O O ~ .
z; t) ~ ~9 o::~ ~ s~ ~ a) a) o o ~ (d ~1 ~ ~ 1:~ SJ~_ Q I ') a) a) S-l (15 a) O ~ al ~
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a) o ~ ~ ~ s~ ~ ~1 o ~ ~ ~ J ~ ~c r ~ ~ .~ ~ ~ o o a) o o ~ o o o s~ ~ ~1 a) m ~ ~ z z; ~ ~4 ~ ~ ~ Q ~ _B:L ~ ~1 ~

., . , .

~55~ ~ 3 Illustrative Example II
~,~
100 parts by weight of the blend number 52 from ~ -Illustrative Example I was reinforced with 65.6 parts by ~ -weight PP~ 0.625 cm glass fi.bre strands by melt blending ! 5the glass fibres with the polymer blend in the extruder ~ -at a temperature of' 240C. The resulting composition had the following properties:
Young's modulus x 103, kPa 7431 Yieldg kPa 50188 ;.; -Tensile at break, kPa 50188 : Ultimate elongation at break, % 1.58 ~-Flex modulus x 103, kPa6081 -Notched Izod impact strength, J/cm o.69 ~ -Illustrative Example III
Glass reinforced blends similar to the one prepared ;;~
in Illustrative Example II were prepared, except that all ~
: four major components plus the glass fibre were dry blended : ~:
;.
together at the same time i.nstead of first preparing the :~
polyblend and then adding the glass fibres.
The various compositions, conditions and test results .
-:
: are presented below in:Table II. In all cases, the resulting :~
polyblends possessed the desired;interlocking network structure.

:

-56- ~ 374 ;:
TABLE II
Blend No. 56 58 Component~ parts by weight Block copolymer 3.5 6.8 Oil o 7 1.7 Nylon 6 15.0 Nylon 6-12 - 26.1 ;
Polypropylene 41.0 26.1 Glass fibres 39.8 39.2 -; 10 Extrusion temperature,aC 240 240 Properties ~ j . .
Young's modulus x 10~
kPa 7487 5522 ~::
Yield, kPa 51498 52877 ~ ~
Tensile at break, kPa 51498 52877 : .
Ult:imate elongation at break, % 1.21 1.78 Flex modulus x 103, -kPa 5943 ~ 4957 ~Notched Izod lmpact strength, J/cm0.72 ~ o.63 .
~ - Illustrative Example IV ~ :
..
Vari~ous polymer blends contain1ng Nylon 6:were:prepared. ~ :~
This Example shows that the presence of the block copolymer : 25 is essential for the success of the invention. All blends ~:
; were prepared by mixing on the extruder at 230C. ~he '' _57~ 3~ 4 compositions are presented below in Table III. (Note, some blends are also presented in Table I).
Blends 18, 12 and 41 are presented for comparison purposes and contain either Nylon 6 by itself or Nylon 6 with polypropylene, while blends 14-17 and 43 reveal blends of the present invention having at least two continuous interlocking networks.
TABLE III
Blend No. 18 12 14 1516; 17 41 43 -~lO Component, parts by weight . ,;
Block copolymer - - 4.2 8.3 12.5 25.0 - 25.5 Oil - _ o.8 1.7 2.5 s.o - 11.5 Nylon 6 loo 50 47 - 5 4542.5 35 50 35 PBT ~- - - - ~ ~ 50 35 Polypropylene - 50 47.5 45 42.5 35 ~ - -Toluene solubles Expected (%w) O 0 5 lo 15 30 o 30 Found (%w)1.2 3.1 4.9 10.7 14.0 28.3 o.4 29.2 `-~
HCl solubles ~ .
Expected (%w) 100 50 47.5 45.o 42.5 35 50 35 Found (%w) 98.8 17.8 45.o 42.9 47.6 28.6 2.3 35.3 , The presence (or absencej of a continuous interlocking network was examined by a selective extraction technique.
In this technique, the polymer blend is subjected to a 16-hour Soxhlet extract;on with hot refluxing toluene.
::

.. . . . . ...

5 ~ 3~

Ideally, the hot toluene should extract the block co-polymer and oil, but should not dissolve the PBT or nylon. Then the unextracted portion of the blend is placed in a vessel contalning 6 molar hydrochloric acid (HCl) and shaken for about 20 hours at room temperature. The HCl should dissolve the Nylon 6, but not the poly-propylene or PBT. The unextracted portion of the blend after each extraction is weighed and the weight loss compared with the expected values.
In blend 18, 1.2% of the Nylon 6 was solublë in hot toluene compared to an expected 0% (well within the accuracy of the technique). The remainder of the polymer completely dissolved in the HCl.
Extraction of blends 12 and 41 not containing any of the claimed block copolymer reveals the absence of con-tinuous interlocking networks. In blend 12, 3.1% of the ~
blend was soluble in hot toluene compared to an expected ;;
0%, also well within the accuracy of the technique. How-ever~ only 17.8~ of the extracted blend was soluble in HCl compared to an expected 50%. This indicates that a large portion of nylon was so encapsulated in the poly-propylene as to be inaccessible to the HCl, i.e., there was no continuous network of nylon that would be accessible to the HCl. In blend 41, 0.4% of the blend of PBT and Nylon 6 was soluble in hot toluene compared to a theoretical 0%. However, only 2.3% of the extracted blend -5~ i374 was soluble in HC1 compared to an expected 50%, ln-dicating a lack of a continuous interlocking network since apparently only a small portion of nylon was accessible to the HCl.
Contrary to the results in blends 12 and 41, the extraction technique reveals the presence of continuous interlocking networks in blends 14-17 and 43, wherein the block copolymer of the instant invention is employed.
For example, in blend 14, 4.2 parts by weight block co-polymer are employed. The toluene extracted 4.9%~
compared to an expected 5%, and most significantly, the HCl extracted 47.5% compared to an expected 45.0%, all within the accuracy of the technique. This indicates that the nylon was present as a continuous network since apparently all the nylon was accessible to the HCl as would be expected from a completely connected phase. :
Similar results are shown for the other polymer blends prepared according to the present invention.
Comparative Example I
In the comparative Example I~ various blends of Nylon 6 and other engineering thermoplastics were prepared in the absence~of the present block copolymer.
The various blends are presented below in Table IV
along with individual remarks concerning the blend.

.

., , ~
.:. ' ,; . ::' -60~ 3~

TABLE IV ~ ~-Blend Engineering Weight Processing Comments No. thermoplastic ratio of temperature resin (Eng. Nylon 6 (C) th.) to Eng.
Th.
:
12 Polypropylene 1:1 235 Grainy appearance 41 PBT 1:1 240 Weak melt hand take off 68 PBT 1:1 265 Not strandable ~
110 Polycarbonate 1:3 270 Melt fracture, ~ ;
extreme die swell surging 114 Polyurethane 3:1 240 Surging, grainy 115 Polyacetal 3:1 ~ 230 Die swell, surging~
melt fracture .
116 PBT 3:1 245 Die swell, slight melt fracture ~; ~ 117 Polycarbonate 3:1 270 Surging, gross melt fracture, die swell 118 Poly(ether 3:1 300 Slight surging, sulphonej strand dimpling (ca~itation) slight melt fracture -61~ 3'~

TABLE IV (cont'd) Blend Engineering Weight Processing Comments No. thermoplastic ratio of temperature resin (Eng. Nylon 6(C) :~
th.) to Eng.
Th.
__ 121 Fluoropolymer 3:1 300 Surging extreme, knobby gross ., . ,~
profile ~:~
176 Poly(acrylo- 1 3 250 No comparison :~ ~ nitrile-co- made ; .
~ styrene) :

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.

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-~:

Claims (32)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A composition containing a partially hydrogenated block copolymer comprising at least two terminal polymer blocks A of a monoalkenyl arene having an average molecular weight of from 5,000 to 125,000, and at least one intermediate polymer block B of a conjugated diene having an average mole-cular weight of from 10,000 to 300,000, in which the terminal polymer blocks A constitute from 8 to 55% by weight of the block copolymer and no more than 25% of the arene double bonds of the polymer blocks A and at least 80% of the aliphatic double bonds of the polymer blocks B have been reduced by hydrogenation, characterized in that the composition comprises:
(a) 4 to 40 parts by weight of the partially hydro-genated block copolymer;
(b) a polyamide having a number average molecular weight in excess of 10,000;
(c) 5 to 48 parts by weight of at least one dissimilar engineering thermoplastic resin being selected from the group consisting of polyolefins, thermoplastic polyesters, thermoplastic cellulosic esters, poly (aryl ethers), poly(aryl sulphones), polycarbonates, acetal resins, thermoplastic polyurethanes, halo-genated thermoplastics, and nitrile resins, in which the weight ratio of the polyamide to the dissimilar engineering thermoplastic resin is greater than 1:1 so as to form a polyblend wherein at least two of the polymers form at least partial continuous interlocked networks with each other.

2. A composition as claimed in claim 1, in which the polymer blocks A have a number average molecular weight of from 7,000 to 60,000 and the polymer blocks B have a number average molecular weight of from 30,000 to 150,000.

3. A composition as claimed in claim 1, in which the terminal polymer blocks A constitute from 10 to 30% by weight of the block copolymer.

4. A composition as claimed in claim 1, in which less than 5% of the arene double bonds of the polymer blocks A and at least 99% of the aliphatic double bonds of the polymer blocks B have been reduced by hydrogenation.

5. A composition as claimed in claim 1 in which the dis-similar engineering thermoplastic resin has an apparent crystal-line melting point in excess of 120°C.

6. A composition as claimed in claim 5, in which the dis-similar engineering thermoplastic resin has an apparent crystal-line melting point of between 150°C and 350°C.

7. A composition as claimed in claim 1, in which the dis-similar engineering thermoplastic resin is a polyolefin having a number average molecular weight in excess of 10,000 and an apparent crystalline melting point of above 100 C.

8. A composition as claimed in claim 7, in which the polyolefin is a homopolymer or copolymer derived from an alpha-olefin or 1-olefin having 2 to 5 carbon atoms.

9. A composition as claimed in any one of claim 7 or 8, in which the number average molecular weight of the polyolefin is in excess of 50,000.

10. A composition as claimed in any one of claim 7 or 8, in which the apparent crystalline melting point of the polyole-fin is between 140°C and 250°C.

11. A composition as claimed in claim 7, in which the com-position contains an isotactic polypropylene.

12. A composition as claimed in claim 7, in which the com-position contains a polypropylene being a copolymer which contains ethylene or another alpha-olefin as comonomer in an amount in the range of from 1 to 20% by weight.

13. A composition as claimed in claim 7, in which the com-position contains poly(1-butene) as polyolefin.

14. A composition as claimed in claim 7, in which the com-position contains as polyolefin a homopolymer of 4-methyl-1-pentene having an apparent crystalline melting point of between 240 and 250°C and a relative density of between 0.80 and 0.85.

15. A composition as claimed in claim 7, in which the com-position contains as polyolefin a copolymer of 4-methyl-1-pentene and an alpha-olefin.

16. A composition as claimed in claim 19, in which the composition contains as polyolefin a copolymer of 4-methyl-1-pentene and a linear alpha olefin having from 4 to 18 carbon atoms, the linear alpha-olefin being present in an amount in the range of from 0.5 to 30% by weight.

17. A composition as claimed in claim 1, in which the dis-similar engineering thermoplastic resin is a thermoplastic poly-ester having a melting point in excess of 120°C.

18. A composition as claimed in claim 1 or 17, in which the dissimilar engineering thermoplastic resin is poly(ethylene terephthalate), poly(propylene terephthalate) or poly(butylene terephthalate).

19. A composition as claimed in claim 1 or 17, in which the dissimilar engineering thermoplastic resin is poly(butylene terephthalate) having an average molecular weight in the range of from 20,000 to 25,000.

20. A composition as claimed in claim 1, in which the engineering thermoplastic resin is a polycarbonate having the general formula:

I
or II

wherein Ar represents a phenylene or an alkyl, alkoxy, halogen or nitro-substituted phenylene group, A represents a carbon-to-carbon bond or an alkylidene, cycloalkylidene, alkylene, cyclo-alkylene, azo, imino, sulphur, oxygen, sulphoxide or sulphone group, and n is at least two.

21. A composition as claimed in claim 1, in which the engineering thermoplastic resin is a homopolymer of formaldehyde or trioxane.

22. A composition as claimed in claim 1, in which the engineering thermoplastic resin is a polyacetal copolymer.

23. A composition as claimed in claim 1, in which the engineering thermoplastic resin is a homopolymer or copolymer derived from tetrafluoroethylene, chlorotrifluoroethylene, bromotrifluoroethylene, vinylidene fluoride and vinylidene chloride.

24. A composition as claimed in claim 1 in which the engineering thermoplastic resin is a nitrile resin having an alpha,beta-olefinically unsaturated mononitrile content of greater than 50% by weight.

25. A composition as claimed in claim 24, in which the alpha,beta-olefinically unsaturated mononitrile has the general formula:

wherein R represents hydrogen, an alkyl group having from 1 to 4 carbon atoms or a halogen.

26. A composition as claimed in claim 24 or 25, in which the nitrile resin is a homopolymer, a copolymer, a graft of a co-polymer onto a rubbery substrate or a blend of homopolymers and/
or copolymers.

27. A composition as claimed in claim 1, in which the composition contains the block copolymer and the dissimilar thermoplastic resin in an amount of from 8 to 20 parts by weight and from 10 to 35 parts by weight, respectively.

28. A composition as claimed in claim 1, in which the com-position contains an extending oil in an amount of from 0 to 100 phr.

29. A composition as claimed in claim 28, in which the composition contains an extending oil in an amount of from 5 to 30 phr.

30. A composition as claimed in claim 1, in which the composition contains a flow-promoting resin as additional resin in an amount of from 0 to 100 phr.

31. A composition as claimed in claim 30, in which the composition contains a flow-promoting resin as additional resin in an amount of from 5 to 25 phr.

32. A composition as claimed in claim 40 or 41, in which the composition contains an additional resin selected from the group consisting of an alpha-methylstyrene resin, coumarone-indene resins, vinyl toluene-alpha-methylstyrene copolymers, polyindene resins and low molecular weight polystyrene resins.