EP0221908A1

EP0221908A1 - Thermoplastic articles receptive to automotive paints

Info

Publication number: EP0221908A1
Application number: EP86901628A
Authority: EP
Inventors: John F. Aleckner, Jr.; David J. Cherry; Lee R. Spencer, Jr.
Original assignee: RESEARCH POLYMERS INTERNATIONAL
Current assignee: RESEARCH POLYMERS INTERNATIONAL
Priority date: 1985-02-21
Filing date: 1986-02-19
Publication date: 1987-05-20
Also published as: WO1986004912A1; JPS62502265A; KR880700016A; EP0221908A4

Abstract

Un procédé de formation d'objets ayant une réceptivité élevée aux peintures pour automobiles comprend le moulage de mélanges des composants (A), (B) et (C), la combinaison de (A) + (B) + (C) étant telle que: 0,18 <= B/(A + B) ,+ 0,91 et 0,43 <= C/(A + B) <= 1,51. A est un copolymère d'un acide carboxylique éthyléniquement insaturé et d'éthylène, B est un élastomère compatible avec les composants (A) et (C) et C est un polymère ou un copolymère cristallin de propylène. Ces parties ainsi formées ont une excellente réceptivité à la peinture, une large plage de valeurs de rigidité et une résistance élevée aux impacts et aux tensions. Elles conviennent pour des applications modernes de l'industrie automobile, telles que des pare-chocs, calandres et des couvre-roues.A method of forming objects having high receptivity to automotive paints comprises molding mixtures of components (A), (B) and (C), the combination of (A) + (B) + (C) being such that: 0.18 <= B / (A + B), + 0.91 and 0.43 <= C / (A + B) <= 1.51. A is a copolymer of an ethylenically unsaturated carboxylic acid and ethylene, B is an elastomer compatible with components (A) and (C) and C is a crystalline polymer or copolymer of propylene. These parts thus formed have an excellent receptivity to painting, a wide range of stiffness values and a high resistance to impacts and tensions. They are suitable for modern applications in the automotive industry, such as bumpers, calenders and wheel covers.

Description

THERMOPLASTIC ARTICLES RECEPTIVE TO AUTOMOTIVE PAINTS

This application is a continuation-in-part of our co- pending United States Patent Application Serial No. 703,833 filed February 21, 1985, entitled Paintable Thermoplastic Polymer Blends With Polypropylene.

BACKGROUND OF THE INVENTION A method of forming articles having a high receptivity toward automotive paints by molding blends of (A) , (B) , and (C) components, the combination of (A) + (B) + (C) being such to satisfy:

0.18 < B/(A + B) < 0.91 and,

0.43 < C/(A + B) < 1.51 and A is a copolymer of an ethylenically unsaturated carboxylic acid and ethylene,

B is an elastomer compatible with components (A) and (C) and C is a crystalline polymer or copolymer of propylene. Such formed parts have excellent paintability, a broad range of stiffness values and high impact and tensile strengths suitable for modern motor vehicle applications such as bumpers and facias and wheel covers. References cited:

4,480,065 10/84 Kawai et al.

4,439,573 3/84 Fukui et al.

4,412,016 10/83 Fukui et al.

This invention relates to a method of forming articles having a high receptivity toward automotive paints by molding blends of (A), (B) , and (C) components and to such articles.

The polymer arts are replete with various disclosures of polymer blends. One particularly desirable class of polymer blends is one which can be used to form lightweight and durable articles. Such lightweight and durable articles have wide utility in the fabrication of finished products, such as in the fabrication of automobile parts, housings for various types^* or equipment, toys and other types of finished products. When such lightweight and durable blends are uti¬ lized in producing the finished products it is often desirable to paint such articles. Unfortunately, it has been found that with polymer blends that include components such as polypropylene and rubber, it is very difficult to paint articles formed therefrom with the paint being securely and durably adhered to the finished articles. The problem of paint adhesion is particularly difficult to solve when such polymer compositions as the well known TPO (thermoplastic olefin) compositions are utilized.

Kawai U.S. Patent 4,480,065 identifies TPO blends as being generally very desirable for such applications as ". . automobile bumpers, bumper skirts, trims, etc. . ."

In fact, it is well known that the TPO blends have very desirable properties for many automotive applications. The one major disadvantage of all TPO blends has been the poor adhesion of automotive paints to formed TPO articles.

The patent literature contains many examples of TPO com¬ positions which claim improved paint adhesion over previous compositions. Fukui et al. U.S. Patent 4,412,016 and Fukui et al. U.S. Patent 4,439,573 both claim improved TPO blends for bumper applications which exhibit improved "lacquer-bonding property."

These references are cited to demonstrate that TPO blends are useful for a wide variety of automotive applica¬ tions and that many inventors have worked toward improving the paint receptivity of these materials. The utility of TPO blends would be expanded in automo¬ tive and other markets should the adhering of paints, sealants and adhesives to them be made easier. Other pro¬ mising non-typical applications include flocked sheets for trunk liners and decorative rub strips which are now made of other plastics such as PUC to which paints adhere more readily.

It is well known in the art that TPO type compositions are thermoplastic blends which are in effect mechanically blended compositions of synthetic rubber and polyolefins, such as polypropylene and polyethylene. TPO compositions are widely used in industry for fabricating lightweight and durable products for„ use in the automotive industry and in various other applications. TPO type products have gained wide acceptance in the automotive industry as a replacement for steel bumpers, body parts and the like. Because of the desirability of such materials for applications in the auto¬ motive industry, it is highly desirable to be able to paint such articles in such a fashion that there is little visible difference between such articles and the metallic parts of the vehicle.

Unfortunately, when polymer compositions are formulated that contain relatively high amounts of polypropylene and/or rubber, it is often difficult to paint products from such compositions with the paint adhering to the products for long periods of time. It has been observed that when pro¬ ducts are produced from compositions that have high amounts of polypropylene and/or rubber therein that the paint will either not initially adhere to the product or it will peel or chip away under normal field use or under high humidity conditions, or in the presence of fuels or solvents.

Various methods have been used to make products that have relatively high amounts of polypropylene and/or rubber therein more paint receptive. The use of primers such as chlorinated polyolefins and plasma surface treatment or other electronic surface treatments have met with good suc¬ cess. However, such conventional methods for increasing the paint receptive nature of molded articles that have relati¬ vely high amounts of polypropylene and/or rubber therein are expensive, and time consuming.

As noted, previous attempts to improve paint receptivity of TPO have involved the use of chlorinated polymers as adhesion promoters. See Fukui et al. U.S. Patent 4,439,573. These chlorinated adhesion promoters are required to achieve adhesion suitable for motor vehicle application. Nevertheless, even with the use of adhesion promoters, the gasoline and solvent resistance of these painted TPO parts is marginally suitable for parts which may be exposed to gasoline.

It is therefore apparent that there is a need to produce polymer compositions that can be utilized to form paint receptive, durable and lightweight products which do not require surface pre-treat ent.

Blends similar to those utilized in accordance with the invention have been used for years for film and packaging applications. What is novel, however, is the use of these blends to achieve remarkable and unexpected improvements in paint receptivity with automotive paints, while at the same time preserving the other desirable properties of TPO blends.

SUMMARY OF THE INVENTION

It is an object of this invention to provide a polymer blend that can be formed to produce various articles with such formed articles having paint receptive surfaces. (The term "paint" is used herein to include all types of coatings such as primers, surface treatments, adhesives, sealants and anything that may be applied to the surface of an article formed from these polymer blends, for the purpose of effecting adhesion to it.) It is yet another object of this invention to provide a polymer blend that can be utilized to form lightweight and durable finished articles which have a paint receptive surface that will allow such articles to be painted, the paint coating being very durable.

It is another object of this invention to provide appropriate coating systems and coating additives and sur¬ face treatments that may be employed to achieve the desired adhesion to the polymer blend of the invention.

What has been discovered is a method of forming func¬ tional and decorative parts such as automobile bumpers, bumper skirts, trims, wheel covers, motorcycle fenders, etc. for use on motor vehicles, the parts being painted with paint systems used in the automotive industry and the painted parts exhibiting excellent appearance, and durabi¬ lity.

The parts are formed by molding a blend of (A) , (B) , and (C) components, the combinations of (A) + (B) + (C) being specific and identified, such that:

(A) is a copolymer of ethylene and an ethylenically unsaturated carboxylic acid,

(B) is an elastomer which is compatible with components (A) and (C) and

(C) is a crystalline polypropylene homopolymer or crystalline polypropylene copolymer of ethylene. The mixing ratio of these components is such as to satisfy:

0.18 < B/(A + B) < 0.91 and,

0.43 < C/(A + B) < 1.51 and preferably to satisfy:

0.62 < B/(A + B) < 0.77 and

0.54 < C/(A + B) 1.31 In addition to the aforementioned required components, other compatible polymers, fillers, reinforcing agents, pigmenting agents, stabilizers and the like can be added to the composition.

In fact, some processing aids such as the metal car- boxylates improve paint adhesion. Also found to improve paint adhesion is the use of titanate coupling agents on the fillers. The polymer compositions of this invention can be molded or otherwise formed to produce finished articles that are lightweight, durable and have surfaces that are paint receptive whereby the finished articles can be painted and the paint cured at temperatures up to 300° F. and the paint coat will adhere to the articles to produce a durable and attractive finish. In accordance with the invention, compositions are employed which can withstand an elevated temperature, for example 300° F. A composition withstands such a temperature when it does not thermally degrade, as by charring, or distort in shape to the point when it is not usable for its intended function (including fitting with other parts) at that temperature or when cooled down.

It has also been discovered that coatings such as paint, primers, sealants, adhesives and surface treatments which give the best adhesion to this polymer blend are those which have carboxylic acid functional group of the ethylene acry¬ lic acid and ethylene methacrylic acid copolymers. Examples of some of these reactive components include but are not limited to epoxy resins, carbodiimides, enamines, keti ines, amines, and isocyanates. These and other components capable of reacting with carboxylic acid functional groups are well known in the coatings industry and have been used for years not only to impart adhesion to many substrates but also to react with free acid in some formulations to prevent unde¬ sirable acid catalyzed reactions.

Polymer compositions useful for producing shaped, paint receptive motor vehicle parts such as wheel covers, for example, are molded from a blend of (A), (B) , and (C) components. Various other compatible polymers, fillers, reinforcing agents, stabilizers and pigment materials can be added to the polymer composition with the resulting polymer blend being capable of being formed into finished articles that have highly paint receptive surfaces.

Component (A) is a copolymer of ethylene and an ethyle¬ nically unsaturated carboxylic acid such as acrylic acid or methacrylic acid.

The preferred acid copoylmers are ethylene acrylic acid copolymers (EAA) or ethylene methacrylic acid copolymers (EMAA) . When utilized in the instant invention, they can be any conventional ethylene and acrylic acid copolymer or any conventional ethylene and methacrylic acid copolymer. Blends of these may be used. Such materials are readily available in the market place. Such copolymers are normally produced by the free radical copolymerization of ethylene with acrylic acid or ethylene with methacrylic acid. The resulting copolymers have carboxylic acid groups along the backbone and/or side chains of the copolymer. The preferred ethylene acrylic acid copolymers or ethylene methacrylic acid copolymers that are used in the instant invention have at least about 5 percent by weight of acrylic acid or methacrylic acid monomer units in the polymer chain. Copolymers of the lower acid content may be also be suitable; however, they were not commercially available for evaluation. Also, other higher homologs of the above described ethy¬ lene methacrylic acid copolymers such as ethylene ethacrylic acid or ethylene propacrylic acid copolymers may be suitable for use in this invention. They are not presently commer¬ cially available, so this could be not confirmed.

The melt index of the ethylene acrylic acid or ethylene methacrylic acid copolymers is in the range of from about 1 to 300. The preferred melt index is between 5 and 30 ASTM 1238 condition E.

Component (B) , the elastomer component of the instant invention, can be virtually any elastomer that is compatible or can be rendered compatible with the remaining ingredients of the blend. For example, the elastomer component can be ethylene propylene, ethylene-propylene diene monomer, styrene-butadiene-styrene, acrylonitrile butadiene, bromo- butyl rubber, etc. The term "compatible" is intended to mean that when the components of the blend are combined, the resultant blend can be molded or extruded or formed into parts that have commercial utility.

Table 1 is a list of commercially available elastomers which were evaluated for use in the invention with positive results. TABLE 1

COMMERCIAL ELASTOMERS

GIVING POSITIVE RESULTS

NAME Type SUPPLIER

Polysar 306 Ethylene-Propylene Polysar Polysar X2 Bromobutyl Polysar Krynac 19.65 Nitril Rubber Polysar Nordel 2722 Ethylene-Propylene-Hexadiene DuPont Vistalon 719 Ethylene-Propylene Exxon Kraton G 11650 Styrene Ethylene Butadiene Shell

Styrene

Stereon 840 A Styrene Butadiene Firestone GE 7340 Hydrogenated Styrene Butadiene Goldsmith & Eggleton

Natsyn2200 Polyisoprene Goodyear

The elastomer composition of this invention is pre¬ ferably comprised of an uncured ethylene-higher-=s-olefin copolymer which consists essentially of 40-85% ethylene and 15-60% of propylene, and having Mooney viscosity ML (1 & 8) at 250°F from 10 - 80; The ethylene-higher^-olefin copolymer may additionally contain up to about 12% of a diene such as 1,4 - hexadiene, norbornenes, alkylidene norbornenes, alke¬ nyl norbornenes, dicyclopentadiene and the like. The higher -olefin which is polymerized with ethylene to form the elastomer component can be any dissimilar °^*<-olefin of 3-12 carbon atoms such as propylene, pentene-1, hexene-1, heptene-1, octene-1, dodecene, 4-methylpentene-l, 3-methylbutene-1, vinylcyclohexane and the like. Preferably the dissimilar higher^~<-olefin is propylene. The ethylene °<-olefin, especially propylene copolymers, and methods of their preparation are well known in the art as for example, in U.S. Pat. No. 2,824,090.

The polypropylene component, component (A) , of the pre¬ sent invention can be any conventional polypropylene. The preferred polypropylene components of the instant invention are polypropylenes having a melt index of from about 0.1 up to about 30. It has been found that polypropylene having a melt index in this range can be effectively blended with the other components of the invention to produce polymer blends that can be effectively molded or extruded, or otherwise formed to produce relatively low cost, lightweight and durable finished products that are paint receptive. The polypropylene component of the invention can be either a homopolymer of propylene or it can be a copolymer of propy¬ lene. When a copolymer of propylene and ethylene is uti¬ lized as the polypropylene component of this invention, the copolymer can either be a random or block copolymer.

We have found that 1-20 MFR (ASTM D1238 Condition E) polypropylene homopolymers and 2-12 MFR random PP copolymers give the best paint adhesion and overall physical properties when used with an ethylene-propylene rubber.

It has been found that when the polypropylene component of the instant invention is increased beyond about 53 weight percent of the entire blend, that the paint adhesion proper¬ ties of the final molded products will decrease significant¬ ly. It has also been found that if the elastomer component of the polymer blend decreases below 10 weight percent, that the paint adhesion properties of the final molded products will drastically decrease. By increasing the elastomer content of the polymer blends above 10 weight percent of the blend, paint adhesion of the final formed product can be further improved. Therefore, in a more preferred embodiment of the invention, the rubber content of the blend is more in the range of about 15 - 60 weight percent. The upper limit of the ethylene acrylic acid or ethylene methacrylic acid copolymer is not particularly critical so long as the other polypropylene and rubber components are present in the above stated amounts. A minimum amount of 6% acid copolymer was required to achieve the desired results in all cases.

It has been found that various other materials can be added to the polymer blends of this invention if desired. Such other materials may include other compatible polymers, such as polyethylene, ethylene ethyl acrylate, ethylene vinyl acetate, etc., and fillers and reinforcing agents such as mica, glass fibers, talc, calcium carbonate, barium sulfate and the like. In some instances, it may also be desirable to add pigmenting agents such as carbon black and the like to the blends of this invention. It has been found that the use of certain acidic carbon blacks enhances the adhesion properties of some of these blends. Also in some instances, it may be desirable to add conventional stabili¬ zers and anti-oxidants to the compositions of this inven¬ tion.

It will of course be understood that mixtures of various materials that fall within the aforementioned components can also be used. For example, the polypropylene component of the invention can be a blend or a mixture of various polypropylenes such as a blend of homopolymer polypropylene along with various propylene copolymers.

The blending or mixing of various components of the instant invention can be carried out using conventional mixing equipment such as Banbury mixers, as well as extru¬ sion mixing equipment. It will be understood that the polymer blends of the instant invention can be blended and then pelletized for easy storage, shipment and subsequent use.

The polymer blends of this invention can be formed into useful articles by any known means such as by extruding the polymer blends, injection molding, blow molding, or thermo- forming. The preferred method is injection molding. Once the blends have been formed into final finished articles, they can be painted with conventional types of paint which contain components which will react with the carboxylic acid in the blend and be sufficiently reactive with the paint, or be of sufficiently high molecular weight so as to anchor themselves in the polymer matrix of the paint. As mentioned previously such components may be epoxides, carbodiimides, enamines, ketimines, amines, iso¬ cyanates or any material that has functional groups capable of reacting with carboxylic acids.

The finished articles may also be treated with any addi¬ tive that will react with the carboxylic acid prior to painting for the purpose of improving paint adhesion. Such treatment may include primers such as epoxy or urethane primers and their components. The paint will adhere to the finished products to form a durable and tough finish that will resist peeling, chipping, high humidity conditions and gasoline. It has been found that the polymer blends of this invention are especially useful for producing finished articles that are painted with u ethane-polyester paints, such as PPG Industries Durethane 700 HSE (High Solids Enamel) .

In order to demonstrate the paint receptive properties of articles made from the polymer blends of this invention, several examples are hereafter reported. In all of the examples, the various polymer blends were prepared by com¬ bining the stated components in the amounts so stated and thereafter subjecting the materials to intensive mixing in a Banbury mixer.

Following the mixing of the materials to prepare a blend of materials, the blends were then used to form test plaques. The test plaques measured approximately 3" x 6" and were approximately 0.125" thick.

In preparing the test plaques for painting, the surfaces of the test plaques were first wiped clean with 1, 1, 1 trichloroethane (TCE). After the TCE evaporated from the surface, the test plaques were all painted by a procedure wherein PPG industries Durethane 700 HSE enamel was applied to the surface of the test plaque. The application of the Durethane 700 HSE was made by spraying the paint in two passes, to entirely coat the plaque surface with each pass. A 1.5 to 2 minute flash time was allowed between each of the passes. The dry film thickness of the paint was between about 1.5 to about 1.8 mils. The PPG Industries Durethane 700 HSE paint that was utilized in all of the tests is a high solids elastomeric enamel that is composed of a polyester urethane backbone. Following the application of both coats of the paint to the surface of the test plaques, the plaques were cured by baking at 250°F for one hour.

Four separate tests we made to evaluate the paint recep¬ tive qualities of the test plaques.

TEST I

In the first evaluation, adhesion 24 hours after painting was tested by taking a test plaque and using a razor knife, X-shaped cross hatch marks were cut through the paint film to the surface of the plaque. Thereafter, 3M Company number 610 tape was applied to the cut area while pressing the tape down with a fingernail or by rubbing the backside of the tape with a pencil eraser. The tape was then removed by rapidly pulling the tape at a 90° angle to the surface to the test plaque. Following the removal of the tape, the plaque surface was examined to detect paint removal. Any paint removal from the test plaque was an indication that the force to remove the paint from the pla¬ que was between 0.3 and 0.7 lbs/inch as determined by Test IV, described herein. This first test was used as a quick screening method to evaluate various blends. TEST II

In the next test to evaluate paint adhesion, a solvent resistance test was utilized. This solvent resistance test has been referred to in the automotive industry as the "Fisher-Body" method. In conducting the test, a painted plaque was immersed in a mixture of 55% naphtha with 45% toluene. Following the immersion in the naphtha-toluene mixture for 10 seconds, the test plaque was removed and allowed to be air dried for 20 seconds. During the drying cycle, scratches with a fingernail or dull knife were attempted over the painted surface. The solvents resistance test was repeated for a number of cycles wherein the test plaque was alternately dipped in the naphtha-toluene for 10 seconds and then allowed to air dry for 20 seconds while the scratching is carried out. Any paint removal as a result of such scratching terminated the test. The results of the solvent resistance tests are given in the number of cycles occurring until there is a removal of the paint from the test plaque.

TEST III

The third test that was utilized to observe the paint adhesion of paint to the polymer blends of this invention utilized test plaques that were painted in accordance with the above-mentioned procedure. The painted plaques were then placed in a humidity chamber that was maintained at 100% humdity at 38°C. The test plaques were removed after 96 hours of exposure and examined for blisters, dulling of paint or any change in paint appearance. Thereafter a razor knife was used to cut X-shaped cross hatches through the paint film to the surface of the plaque and 3 M Company number 610 tape was applied to the cut area while pressing down with a fingernail or rubbing the backside of the tape with a pencil eraser. The tape was then removed by rapidly pulling the tape at a 90 degree angle to the surface of the test plaque. Any removal of the paint from the cut area correlated with a 0.3 - 0.7 lb/inch adhesion value as deter¬ mined by Test IV. In carrying out the humidity resistance test, the examination of the appearance and adhesion was carried out within 10 minutes of the removal of the test plaque from the humidity chamber.

TEST IV Test IV quantitatively measures the force in lbs./in. to peel a 1" wide strip of coating from the molded test pla¬ ques. The test was initiated by pressing a 1" wide strip of tape onto the painted surface. A scribe along each side of the tape is made in the opposite direction of pull. The delamination of the paint from the plaque is initiated by raising the leading edge of the paint with a sharp metal blade. Once started, tape is attached to the backside of the delaminated paint and secured to the traversing clamp of an Instron unit. Using an Instron with a load cell of 0-20 lbs. the paint was pulled at a 90° angle to the plaque.

Using coating thickness of 1.5 - 2.0 mils, values up to 5.0 lbs/in. were measured. It was determined that Test I, a method used by the automotive industry to evaluate paint durability, gave paint delamination at adhesion levels up to 0.7 lbs/in. In some cases, however, paints that had adhe¬ sion values of only 0.3 lbs/in. passed Test I. This appears to be caused by the tendency of the razor blade to force the coating into some of the softer substrates, thereby making it more difficult for the tape to pull it free.

Using the automotive industry guidelines, adhesion levels of 0.8 lbs/in. or greater were considered as being highly durable.

EXAMPLES

Chart I demonstrates the use of homopolymer and copo¬ lymer polypropylene with two ethylene-propylene rubbers and various ethylene acrylic acid copolymers. It can be seen that initial paint adhesion is always improved by the addi- tio of ethylene acrylic acid to the formula. Chart II demonstrates the wide variety of commercial methylene - ethylenically unsaturated carboxylic acid copo¬ lymers which may be successfully used in this invention.

Chart III demonstrates the wide variety of elastomers which can be used in this invention. It was generally found that any elastomer which is or can be made compatible with polypropylene can be used in this invention. Even some incompatible blends demonstrated improved paint receptivity. They were commercially unsuitable, however.

Chart IV demonstrates the superior solvent resistance of the formula containing Primacor 3440. This solvent resistance test. Test II is used to predict paint lift off from gasoline.

Chart I Examples parts by weight

Profax 8623,

2.0 MFI

Copolymer 49 49 49 49 49 49 49

Profax 6723,

0.8 MFI

Homopolymer 49 49 49 49

Nordel 2622 20 5 3 30 33 30 5 20 5 30 36

Polysar 306 26 5 18 15 13 10 5 26 5 15 15

Primacor 3440,

10 MI, 9% Acid

Comonomer 36

Primacor 1410,

1.5 MI, 9% Acid

Comonomer 36 36

Talc 5 5 5 5 5 5 5

Test I F P F P F P P F P P F

Test II - 11 - 20+ - 20+ 9 - 18 20+ 3

Test III - F - F F F - P F

Test IV - 3.2 0 .1 NP 0.1 1.7 1.5 - 1.3 1.5 0.1

Test Codes

NP = Not Able to Peel Coating from Substrate

P = Pass i.e. no paint squares removed

F = Fail i.e. at least one square of paint removed

CHART II EXAMPLES parts by weight

Profax 8623, 2.0 MFI

Copolymer 46 30 30 30 30 30 51 51 53

Nordel 2722 20 20 20 20 20

Polysar306 10 20 20 20 20 20 10

Vist_alon 719 20 20 39 39

Black Concentrate 9 9

Nucrel 0901, 10 MI,

9% Acid Ccmoncmer 15 8

Nucrel 925, 21 MI,

15% Acid Ccmonαner 30

Nucrel 035, 35 MI,

9% Acid Ccmoncmer 30

Primacor 3440, 10 MI,

9% Acid Cbmoncmer 30

Primacor 1410, 1.5 MI t

9% Acid Ccmoncmer 30

Primacor 5981300 MI,

20% Acid Comonomer 30

Primacor 459,9MI,

6.5% Acid Ccmonomer 10 10

Test I P P P P P P P P P

Test II 20+ 20+ 20+ 20+ 20+ 20+ 6 20+ 20+

Test III P P P P P P P F P

Test IV - NP NP NP NP NP - - -

Test Codes

NP = Not Able to Peel Coating from Substrate

P = Pass i.e. no paint squares removed^'

F = Fail i.e. at least one squcire of painit removed

Chart III Examples parts by weight

Profax SB 786,r

8.0 MFI,

Copolymer 45 45 45 45 45 45 45 45 45 45 45 45

Krynac 19.65 30 60

GE 7340 30 60

Polysar SS255 30 60

Polysar X2 30 60

Kraton G 30 60 30

Primacor 3440 30 30 30 30 30

Stereon 840A 30 60

Test I P F P P P P P F P F

Test IV 1.7 0.3 4.2 1.5 4.2 2.8 2.3 0.4 1.1 0.2 NP* 0.1

Test Codes

P = Pass

F = Fail

*NP = Not Able to Peel Coating from Substrate

Chart IV Examples parts by weight

Profax 8623 50 50

Polysar 306 20 35

Primacor 3440 15 -

10MI, 9% acid

HDPE 10 15

Talc 5 5

Painted with PPG Durethane HSE 8574 Over Chlorinated Adhesion Promoter

Test I P P

Test II <3 <3

Test III P P

Paint with PPG Durethane HSE 8574 No adhesion Promoter

Test I P F

Test II <20 <3

Test III P F

In accordance with the invention, the methods of making functional or decorative articles which are used for the manufacture of motor vehicles may include use of various additives selected from anti-oxidants, ultraviolet ray absorbing agents, flame retardants, pigments, lacquer- bonding enhancers, platicizers, lubricants and anti-static agents in the blends.

The anti-oxidants, if employed, may be selected from the group consisting of 2,6-di-tert-butylphenol, 2,6-di-tert- butyl-4-ethylphenol, 2,6-di-tert-butyl-4-n-butylphenol, 2,6-di-tert-butyl-a-dime-thylamino-p-cresol, 6-(4-hydroxy-3,5-di-tert-butylanilino)-2,4-bis-octyl- thio-l,3,5-triazine, n-octadecyl-3-(4'-hydroxy-3, '5' ,-di- tert-butylphenyl) propionate, 2,6-di-tert-butyl-4- methylphenol (BHT) ,tris-(2-methyl-4-hydroxy-5-tert- butylphenyl) butane, tetrakis-[methylene 3-(3' ,5'-di-tert- butyl-4'-hydroxyphenyl) propionate] methane, 1,3,5 - trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, and dilaurylthiodipropionate.

The ultraviolet ray absorbing agents may be selected from the group consisting of 2-hydroxy-4-n-octoxybenzophenone 2-hydroxy-4-octadecyloxy-benzophenone, 4-dodecyloxy-2- hydroxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2-(2*-hydroxy-3'-tert-butyl-5*-methylphenyl)-5- chlorobenzotriazole, 2-(2'-hydroxy-3'5'-di-tert-butylphenyl)- 5-chloro-benzotriazole, nickel-bis-(orthoethyl-3,5-di-tert- butyl-4-hydroxybenzyl) phosphonate and bis (2,6-dimethyl-4- piperidyl) sebacate.

The pigment, if employed, may be selected from the group consisting of carbon black and titanium dioxide, while a pro¬ cess oil is a suitable plasticizer. A satisfactory lubricant comprises a fatty acid metal salt.

When it is desired to use talc as an additive, the talc particles are preferably coated with at least one member selected from organic t.itanate coupling agents, silane coupling agents, fatty acids, fatty acid metal salts and fatty acid esters.

Claims

What is claimed is:

1. An article of manufacture formed of a composition comprising a blend of (A), (B) , and (C) components, the com¬ bination of (A) + (B) + (C) being such as to satisfy:

0.18 < B/(A + B) < 0.91 and 0.43 < C/(A + B) < 1.51 and and said article being painted with a paint containing material reactive to carboxylic acid groups.

2. An article in accordance with Claim 1 in which said components are blended and mixed within said range limita¬ tions such that said article can withstand a temperature of at least 300° F. for at least one hour.

3. An article in accordance with Claim 1 in which said polypropylene is a random copolymer with ethylene.

4. An article in accordance with Claim 1 in which said polypropylene is a block copolymer with ethylene.

5. An article in accordance with Claim 1 in which said elastomer consists essentially of 40-85% ethylene and 15-60% propylene and having a Mooney viscosity M-. (1 + 8) at 260° F. from 10-80.

6. An article in accordance with Claim 1 in which said elastomer is selected from the class consisting of ethylene propylene, ethylene-propylene diene monomer, styrene- ethylene-butadiene-styrene, acrylonitirile butadiene, bromo- butyl rubber, and butadiene-styrene.

7. An article in accordance with Claim 1 in which said elastomer is an uncured ethylene-higher-**-olefin copo¬ lymer containing 40-85% ethylene and 15-60% higher^-olefin is selected from the class consisting of propylene, pentene-1, hexene-1, heptene-1, octene-1- dodecene, 4-methypentene-l, 3-methybutene-l and vinylcyclohexene.

8. An article in accordance with Claim 1 in which said elastomer contains up to 12% of a diene selected from the class consisting of 1,4 hexadiene, norborenes, alkylidene norborenes, alkenyl norborenes, and dicyclopentadiene.

9. An article in accordance with Claim 1 in which said ethylenically unsaturated carboxylic acid copolymer is selected from the class consisting of ethylene acrylic acid copolymers, ethylene methacrylic acid copolymer, and mix¬ tures thereof.

10. An article in accordance with claim 8 in which said ethylenically unsaturated carboxylic acid copolymer has a melt index of 1-300.

11. A method of making functional or decorative articles which are used for the manufacture of motor vehicles and which have a high receptivity for automotive paints comprising forming said article from softened or molten blends of (A), (B) , and (C) components, the com¬ bination of (A) + (B) + (C) being such to satisfy: 0.18 a<m B/(A + B) a<_* 0.91 and

0.43 < C/(A + B) < 1.51 and

(A) is a copolymer of ethylene and an ethylenically unsa¬ turated carboxylic acid,

(B) is an elastomer compatible with components (A) and (C), and

(C) is a crystalline polypropylene homopolymer or a crystalline copolymer of propylene with ethylene. and thereafter hardening said article by allowing it to cool.

12. A method of making functional or decorative articles which are used for the manufacture of motor vehicles and which have a high receptivity for automotive paints from blends of (A), (B) , and (C) components, the com¬ bination of (A) + (B) + (C) being such to satisfy: 0.62 B/(A + B) < 0.77 0.54 < C/(A + B) < 1.31 (A) is a copolymer of ethylene and an ethylenically unsa¬ turated carboxylic acid. (B) is an elastomer compatible with components (A) and (C), and

13. A method of making functional or decorative articles which are used for the manufacture of motor vehicles in accordance with claim 11 wherein the composition further comprises at least one additive consisting of at least one member selected from anti-oxidants, ultraviolet ray absorbing agents, flame retardants, pigments, lacquer- bonding enhancers, plasticizers, lubricants and anti-static agents.

14. A method of making functional or decorative articles which are used for the manufacture of motor vehicles in accordance with Claim 13 and further comprising including in said blend an anti-oxidant, wherein said anti- oxidant comprises at least one member selected from the group consisting of 2,6-di-tert-butylphenol, 2,6-di-tert- butyl-4-ethylphenol, 2,6-ditert-butyl-4-n-butylphenol,

2,6-di-tert-butyl-a-dime-thylamino-p-cresol, 6-(4-hydroxy-3,5-di-tert-butylanilino)-2,4-bis-octyl- thio-l,3,5-triazine, n-octadecyl-3-(4*-hydroxy-3, '5* ,-di- tert-butylphenyl) propionate, 2,6-di-tert-butyl-4- methylphenol (BHT) ,tris-(2-methyl-4-hydroxy-5-tert- butylphenyl) butane, tetrakis-[methylene 3-(3' ,5'-di-tert- butyl-4'-hydroxyphenyl) propionate] methane, 1,3,5 - trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, and dilaurylthiodipropionate.

15. A method of making functional or decorative articles which are used for the manufacture of motor vehicles in accordance with Claim 13 comprising and further including in said blend an ultraviolet ray absorbing agent wherein said ultraviolet ray absorbing agent comprises at least one member selected from the group consisting of 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-octadecyloxy- benzophenone, 4-dodecyloxy-2-hydroxybenzophenone, 2-hydroxy- 4-n-octoxybenzophenone, 2-(2'-hydroxy-3'-tert-butyl-5'- methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3*5*- di-tert-butylphenyl)-5-chloro-benzotriazole, nickel-bis- (orthoethyl-3,5-di-tert-butyl-4-hydroxybenzyl) phosphonate and bis (2,6-dimethyl-4-piperidyl) sebacate.

16. A method of making functional or decorative articles which are used for the manufacture of motor vehicles in accordance with claim 13 and further comprising including in said blend a pigment which is selected from the group consisting of carbon black and titanium dioxide.

17. A method of making functional or decorative articles which are used for the manufacture of motor vehicles in accordance with claim 13 wherein the composition further comprises a process oil as a plasticizer.

18. A method of making functional or decorative articles which are used for the manufacture of motor vehicles in accordance with claim 13 wherein the composition further comprises a lubricant comprising a fatty acid metal salt.

19. A method of making functional or decorative articles which are used for the manufacture of motor vehicles in accordance with claim 13 wherein the composition further contains talc particles which are coated with at least one member selected from organic titanate coupling agents, silane coupling agents, fatty acids, fatty acid metal salts and fatty acid esters.