JPH0286657A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To obtain a thermoplastic resin composition excellent in impact resistance, chemical resistance and molding appearance by mixing a polyamide with a rubber-reinforced resin and a modified graft copolymer. CONSTITUTION:The title resin composition comprises a polyamide (A), a rubber- reinforced styrene resin (B) and a modified graft copolymer (C) constituted of 20-80wt.% ethylene/alpha-olefin rubber, 19.99-79.99wt.% aromatic vinyl monomer, 0.01-20wt.% monomer being reactive with or having an affinity for the polyamide and 0-30wt.% another vinyl monomer copolymerizable therewith, wherein 90-10 pts.wt. component (A), 5-85 pts.wt. component (B) and 5-85 pts.wt. component (C) are present per 100 pts.wt. total of components (A), (B) and (C), and the rubber content of the composition is 5-40wt.%.

Description

[Detailed description of the invention] The present invention relates to a thermoplastic resin composition with excellent composition.

<Conventional technology> Polyamide resin has excellent moldability, heat resistance, mechanical strength, chemical resistance, abrasion resistance, etc., so it is used for mechanical parts, electrical and
Although it is widely used in electronic parts and automobile parts, it has problems such as decreased impact resistance in dry conditions and dimensional changes due to moisture absorption.

On the other hand, typical rubber-reinforced styrene resins include acrylonitrile-butadiene-styrene copolymer (ABS resin), ABS resin in which the rubber component of ABS resin is replaced with ethylene-propylene rubber or acrylic comb, and ABS resin.
AS resins are also widely used in automobile parts, electrical equipment parts, office equipment parts, etc., and although they have excellent impact resistance and dimensional stability, they have the problem of relatively poor chemical resistance.

Polyamide and ABS to improve these problems
It has been proposed to melt and mix resins (Tokuko Sho 8B
-23476) is known to have poor compatibility between polyamide and ABS resin, resulting in molded products exhibiting delamination and resulting in only materials with low impact strength.

In order to improve the compatibility between polyamide and ABS resin, a carboxylic acid having reactivity or affinity with polyamide,
It has been proposed to introduce and modify functional groups such as amide groups into ABS resins (JP-A-54-11159, JP-A-58-32656, JP-A-58-98745, etc.); There are problems in that the appearance of the molded product deteriorates and the impact strength is not sufficiently improved.

<Problems to be Solved by the Invention> As a result of intensive studies by the present inventors on improving the above-mentioned quality problems of compositions made of polyamide resin and rubber-reinforced styrene resin, the present inventors found that The inventors have discovered that a material with excellent impact resistance, chemical resistance, and molded product appearance can be obtained by mixing a resin and a specific modified graft copolymer in a specific ratio, and have thus arrived at the present invention.

Means for Solving the Problems> That is, the present invention consists of (3) polyamide, (Bl rubber reinforced styrenic resin and (q 20 to 80% by weight of ethylene-α olefin rubber, aromatic vinyl monomer) 1999-7999% by weight, 0.01-20% by weight of monomers having reactivity or affinity for polyamide, and 0-30% by weight of other copolymerizable vinyl monomers.
(3)
), ■ and (q to 100 parts by weight, (A
) 90 to 1.0 parts by weight, (Bl 5 to 85 parts by weight and (05 to 85 parts by weight), and the rubber content in the composition is 5 to 40% by weight. The present invention provides a thermoplastic resin composition with excellent chemical resistance and molded product appearance.

Hereinafter, the present invention will be explained in detail.

The polyamide (A) used in the present invention includes ethylene diamine, diaminobutane, hexamethylene diamine, decamethylene diamine, dodecamethylene diamine, 2
, 2,4- and 2゜4, 4-1-limethylhexamethylenediamine, ■, 3 and 1,4-bis(aminomethyl)cyclohexane, bis(P-aminocyclohexyl)methane, metaxylylenediamine, Aliphatic, alicyclic, aromatic diamines such as xylylene diamine and aliphatic such as adipic acid, speric acid, sebacic acid, cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid,
Polyamides derived from alicyclic and aromatic dicarboxylic acids; polyamides obtained by ring-opening polymerization of lactams such as ξ-caprolactam and ω-dodecalactam, 6-aminocaproic acid, 11-aminoundecanoic acid, and 12-aminododecane. Examples include polyamides derived from acids, copolyamides thereof, mixed polyamides, and the like.

Polycaproamide (nylon 6), boddecamide (nylon 12), polytetramethylene adipamide (nylon 46), and polyhexamethylene adipamide (nylon 6) are industrially produced at low cost and in large quantities.
6) Ponohexamethylene sebamide (nylon 610
), and copolymers thereof, such as nylon 6/6
6 ('/7' mark means it is a copolymer), nylon 6/61.0, nylon 6/12, nylon 66
Nylon 6/66/610/12, and mixtures thereof are useful. Also useful are bis(p-aminocyclohexyl)methane/terephthalic acid/isophthalic acid based polyamides.

Note that there is no limit to the degree of polymerization of the polyamide used;
Concentrated sulfuric acid relative viscosity (polymer 12 98% concentrated sulfuric acid 100
rptt and measured at 25°C, the same applies hereinafter) is 1.8
Any polyamide within the range of .about.6.0 can be selected.

There are no restrictions on the molecular structure of polyamide, and either linear polyamide, branched polyamide, etc. may be used. Linear polyamide is produced by conventional methods,
Branched polyamide is polymerized by adding a small amount of a branching agent having three or more functional groups capable of forming a polyamide, such as bis(ω-aminohexyl)amine, diethylenetriamine, trimesic acid, and bislactam, to the raw material. Polymerization methods include melt polymerization, interfacial polymerization, solution polymerization, bulk polymerization, solid phase polymerization, and combinations of these methods, with melt polymerization being most suitable for certain purposes. In addition, especially when the polyamide raw material is a lactam, the polymer may be obtained by anionic polymerization.

The rubber-reinforced styrenic resin in the present invention refers to 50 to 100% by weight of aromatic vinyl monomer in the presence of a rubbery polymer.
and a graft copolymer obtained by polymerizing a monomer mixture consisting of 0 to 50% by weight of other copolymerizable vinyl monomers, or such a graft copolymer and 50 to 1% by weight of an aromatic vinyl monomer.
00% by weight and other copolymerizable vinyl monomers 0-5
It is a mixture with a styrenic polymer consisting of 0% by weight.

Graft copolymers (rubber-like polymers used here include diene rubber-like polymers such as polybutadiene, butadiene-styrene copolymer, butadiene-acrylonitrile copolymer, and ethylene-propylene copolymer, ethylene-propylene- Examples include non-diene rubber polymers such as non-conjugated diene copolymers, acrylic rubber polymers, and chlorinated polyethylene, which can be used alone or in combination of two or more.These rubber polymers is manufactured by emulsion polymerization, solution polymerization, bulk polymerization, suspension polymerization, etc.

There are no particular restrictions on the particle size and gel content of the rubbery polymer when produced by emulsion polymerization, but the average particle size is 0.1 to 1 μm and the gel content is 0 to 9.
Preferably it is 5%.

Examples of aromatic vinyl monomers include styrene, α-methylstyrene, 0-methylstyrene, m-methylstyrene, and p-methylstyrene.
Examples include -methylstyrene, t-butylstyrene, α-methylvinyltoluene, dimethylstyrene, chlorostyrene, dichlorostyrene, bromustyrene, dibromostyrene, and the like, which can be used alone or in a mixture of two or more.

Other vinyl monomers that can be copolymerized with aromatic vinyl monomers include vinyl cyanide monomers such as acrylonitrile and methacrylate, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, and methyl. unsaturated carboxylic acid alkyl esters such as methacrylate, ethyl methacrylate, propyl methacrylate, 2-ethylhexyl methacrylate;
Maleimide compounds such as maleimide, N-phenylmaleimide, N-methylmaleimide, and N-cyclohexylmaleimide are exemplified and can be used alone or in combination of two or more.

There is no particular restriction on the ratio of the rubbery polymer to the monomer mixture in the graft copolymer, but the rubbery polymer 20 to 8
Preferably 0% by weight and 80-20% by weight of the monomer mixture.

Further, there is no particular restriction on the grafting rate of the graft copolymer, but it is preferably 20 to 100%.

As the graft polymerization method, known methods such as emulsion polymerization, suspension polymerization, solution polymerization, bulk polymerization, or a combination thereof are used.

The aromatic vinyl monomer and other copolymerizable vinyl T414 monomer constituting the styrenic polymer used in combination with the graft copolymer are the same as the monomer used in the graft copolymer. These are listed as examples, and they can be used alone or in two or more dishes. Although there is no particular restriction on the molecular weight of the styrene polymer, it is preferable that the weight average molecular weight is 10,000 to t, ooo, ooo. As a polymerization method for the styrenic polymer, known methods such as emulsion polymerization, suspension polymerization, solution polymerization, bulk polymerization, or a combination thereof are used.

The modified graft copolymer used in the present invention includes 20 to 80% by weight of ethylene-α olefin rubber, 19.99 to 7999% by weight of aromatic vinyl monomer, and has reactivity or affinity for polyamide. It is a copolymer composed of 0.01 to 20% by weight of a monomer and 0 to 30% by weight of another copolymerizable vinyl monomer.

The ethylene-α olefin rubber that constitutes the modified graft copolymer is a binary copolymer (EPR) consisting of ethylene and propylene or butene, or a terpolymer (EPR) consisting of ethylene, propylene or butene, and a non-conjugated diene. EP
DM), etc., and one or more types may be used.

Non-conjugated dienes in the terpolymer (EPDM) include dicyclopentadiene, ethylidene norbornene,
1.4-hexadiene, 1.4-cyclohebutadiene,
(2), 5-cyclooctadiene, and the like.

Binary copolymers (EPR) and terpolymers (EPDM)
The molar ratio of ethylene to propylene or butene in ) is preferably in the range of 5:1 to 1:3.

Further, in the terpolymer (EPDM), it is preferable that the proportion of non-conjugated diene is in the range of 2 to 50 in terms of iodine value.

Examples of the aromatic vinyl monomer include those mentioned in the section of the rubber-reinforced styrenic resin (B), and one or more of them can be used.

Examples of monomers that have reactivity or affinity for polyamide include vinyl monomers that have a functional group that reacts with or has affinity for the terminal carboxylic acid group or amino group of polyamide. Vinyl monomers having a functional group such as a carboxylic acid group, an acid anhydride group, an amino group, a hydroxyl group or a poxy group can be used, and one type or two or more types can be used.

Examples of the vinyl monomer having a carboxylic acid group include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, etc., and one or more types can be used.

Examples of the vinyl monomer having an acid anhydride group include maleic anhydride, citraconic anhydride, chloromaleic anhydride, etc., and one or more types thereof can be used.

Examples of the vinyl monomer having an amino group include acrylamide, methacrylamide, aminoethyl acrylate, dimethylaminoethylmethacrylate, diethylaminomethacrylate, etc., and one or more of them can be used. As a vinyl monomer having an epoxy group,
Examples include glycidyl acrylate and glycidyl methacrylate, and one or more types can be used.

Examples of the vinyl monomer having a hydroxyl group include hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, and hydroxypropyl methacrylate, and one or more of them can be used.

Other copolymerizable vinyl monomers include those mentioned in the section of the rubber-reinforced styrenic resin (A), and one or more of them can be used.

The composition ratio of the above-mentioned ethylene-α olefin rubber, aromatic vinyl monomer, monomer having reactivity or affinity for polyamide, and copolymerizable vinyl monomer is defined in the present invention. Outside the range, the desired composition cannot be obtained.

Preferably, ethylene-α olefin rubber 25 to 65
% by weight, 24.95-74.95% by weight of aromatic vinyl monomers, 0.05-10% by weight of monomers having reactivity or affinity for polyamides, and 0 copolymerizable monomers.
~20% by weight.

As a method for producing the modified graft copolymer, known methods such as emulsion polymerization, suspension polymerization, solution polymerization, bulk polymerization, or a combination thereof can be employed.

The thermoplastic resin composition of the present invention is made of the above-mentioned polyamide (A
), rubber-reinforced styrenic resin 1 m (consisting of homogeneous and modified graft copolymer (q), whose composition ratio is (A), (consisting of the total amount of homogeneous and (q) 100 parts by weight, (A) 90
~10 parts by weight, ■5 to 85 parts by weight, and (05 to 85 parts by weight), and the rubber content in the composition is 5 to 40% by weight.

If the composition ratios of (2), (B), and (q) are outside the above range, the impact resistance, chemical resistance, or appearance of the molded product will be poor.

Preferably cA) 80 to 20 parts by weight, (11110 to 7
0 parts by weight and 0IO to 70 parts by weight, which is not preferable because it lowers the hardness.

Polyamide (A), rubber-reinforced styrene resin (uniform and modified graft copolymer) There are no restrictions on the mixing order of q, and the three components can be mixed at once, or the remaining one component can be mixed after premixing the two components. can.

Further, there is no restriction on the mixing method, and known methods such as a Banbury E mixer roll or an extruder can be employed.

In addition, when mixing, antioxidants, ultraviolet absorbers, light stabilizers, antistatic agents, lubricants, dyes, pigments, plasticizers, flame retardants, mold release agents, glass fibers, metal fibers,
Additives such as carbon fiber and metal flakes, reinforcing materials, fillers, etc. can be added. Further, thermoplastic resins such as polyacetal, polycarbonate, polybutylene terephthalate, polyethylene terephthalate, polyphenylene oxide, polymethyl methacrylate, polyvinyl chloride, etc. can also be appropriately blended.

Next, the present invention will be specifically explained using Examples and Comparative Examples. Note that all parts and percentages are expressed on a weight basis.

Reference Example 1 Production of Rubber Reinforced Thermoplastic Resin (Bl) 15 parts of acrylonitrile and An ABS graft copolymer latex was prepared by copolymerizing 35 parts of styrene.

B-2 15 parts of acrylonitrile and 35 parts of styrene are copolymerized by an emulsion polymerization method in the presence of 50 parts (solid content) of cross-linked polybutyl acrylate Thirax with an average particle diameter of 03 μ to make an AAS kraft copolymer latte. I created a cookie.

B-3 iodine number 153, Mooney viscosity 67, propylene content 50%, and 75 parts of EPDM containing ethylidene norbornene as the diene component were dissolved in 1000 parts of n-hexane and 650 parts of ethylene dichloride, and 75 parts of styrene and 25 parts of acrylonitrile were dissolved. and 3 parts of benzoyl peroxide, polymerized at 67°C for 10 hours under nitrogen atmosphere,
An AES graft copolymer solution was created.

Graft copolymers B-1 and B-2 were salted out using calcium chloride, separated and dried. Graft copolymer B-3 was recovered by pouring the polymerization solution into a large excess of methanol, and separating and drying the precipitate.

When the amount of rubber contained in the graft copolymers B-1, B-2, and B-3 was measured by infrared spectroscopy, it was found to be about 50% in each case.

Reference example 2 Production reference example 1 of modified graft copolymer (C)
The method for producing graft copolymer B-3 was followed in the same manner except that the charging composition was changed, and the composition shown in Table 1 (1) was obtained.
modified kraft copolymer C (measured by infrared spectroscopy)
-1 to C-4 were created.

Table 1 Example Polyamide 8, the rubber-reinforced styrenic resin (B) produced in Reference Example and modified graft copolymer 0 were mixed in the proportions shown in Table 2, and 40. 250℃ using a twin-screw extruder with a diameter of
The mixture was melt-mixed and granulated. The polyamide used was nylon 6 (concentrated sulfuric acid relative viscosity 2.6), and the acrylonitrile-styrene copolymer (AS) was beads produced by a suspension polymerization method with an intrinsic viscosity (dimethylformamide solution, measured at 30°C) of 060. were used, respectively.

The physical properties of the obtained resin composition were measured by the following method,
The results are shown in Table 2.

O Impact strength (notched isot) ASTM D-256 (23°C) O Molded product appearance: A molded product of 150 w x 150 UX 3.18 U was molded, and its appearance (presence or absence of flow marks) was visually evaluated. In addition, the presence or absence of delamination was visually determined for the same molded product by a cross-cut test using an adhesive tape.

O Chemical resistance: A molded product measuring 150 u x 20 ju x 3 m was fixed on a cantilever jig, bent by 30 degrees, and then immersed in various chemicals for 24 hours to determine the presence or absence of cracks.

The above test pieces for quality evaluation were molded using a 3.5-ounce injection molding machine with the cylinder temperature set at 250°C.

<Examples 1 and 2 and Comparative Examples 1 and 2> As shown in Table 2, the effects of the amounts of the rubber-reinforced styrene resin (B) and the modified graft copolymer (q) on the quality are shown.

<Examples 3 and 4> AAS and VI as rubber-reinforced styrene resins An example using All5 and All5 is shown below.

<Examples 5 and 6 and Comparative Examples 3 and 4> The influence of the amount of polyamide (A), rubber-reinforced styrenic resin (styrene resin) and modified graft copolymer (C) and the amount of rubber in the composition on the quality is shown. .

<Examples 7 and 8 and Comparative Example 5> The influence of the composition of modified graft copolymer 0 on quality will be shown.

<Effects of the Invention> The thermoplastic resin composition of the present invention has a better balance of impact resistance, molded product appearance, and chemical resistance than conventional polyamide resin compositions.

Claims (1)

[Claims] (A) polyamide, (B) rubber reinforced styrene resin, and (C) 20 to 80% by weight of ethylene-α olefin rubber
, aromatic vinyl monomer 19.99 to 79.99% by weight,
Monomers with reactivity or affinity for polyamide 0
．． 01 to 20% by weight and 0 to 30% by weight of other copolymerizable vinyl monomers, and the total amount of (A), (B), and (C) is 1
00 parts by weight, (A) 90 to 10 parts by weight, (B) 5
85 parts by weight and (C) 5 to 85 parts by weight, and the rubber content in the composition is 5 to 40% by weight.