JPH0796596B2 - Graft polymer and rubber-reinforced resin composition containing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to a graft polymer having good hue, in particular, a bronze phenomenon solved, and a rubber-reinforced resin composition containing the graft polymer.

<Prior Art> Acrylonitrile-butadiene-styrene polymer, a rubber-reinforced thermoplastic resin typified by so-called ABS resin, is widely used for automobile interior parts, electric appliance housings, etc. because of its good impact resistance. There is.

Further, ethylene-α-olefin rubber, acrylic ester rubber, chlorinated polyethylene, ethylene-vinyl acetate rubber having a content of the conjugated diene monomer of less than 50% by weight have less unsaturated bonds and have weather resistance. Rubber-reinforced resins based on these rubbers have attracted attention because of their excellent properties.
Generally, they are called AES resin, AAS resin (ASA resin), ACS resin, and AEVAS resin, and they are used as weather resistant resins in the field of outdoor use including exterior parts of automobiles.

In particular, the rubber-reinforced resin based on the rubber as described above is often used without coating due to its excellent weather resistance, and therefore appearance and hue are important items.

"ABS resin" published by The Society of Polymer Science, August 31, 1965
As described in many documents including, the rubber-reinforced resin has a form in which grafted rubber particles are dispersed in a resin matrix, and the rubber particles bring about the impact resistance of the resin. is there. In addition, each rubber-reinforced resin has an optimum range of the rubber particle size, and generally, all of these resins have an average rubber particle size of 0.20 to 0.45 μm.

However, this rubber particle size is an average particle size, and in reality
The particle size is as wide as 0.01 to several μ in the elbow, and the particle size that has been discussed in the literature on the reinforced resin to date means that particles with a broad particle size distribution are usually simply weight averaged (in some cases, (Number average). One of the reasons for this is that industrially producing a rubbery polymer having a narrow particle size distribution is technically complicated and economically inferior.

On the other hand, the rubber-reinforced resin is usually colored by blending a colorant and is used as a colored molded product.

"Metamerism" is one of the important things to note in the toning and coloring process, but this is a phenomenon in which the color changes when the light source changes. For example, it is often seen that the colors under room lighting do not match the colors under sunlight. This phenomenon is due to the colorant,
It can be solved by selecting a colorant.

In addition, this phenomenon can be easily judged with the naked eye,
It can be confirmed by a spectrophotometer as a numerical value (reflectance) or a graph (reflectance curve).

<Problems to be Solved by the Invention> However, the colored molded article has a problem such as "bronze phenomenon" as well as the above-mentioned metamerism.

The "bronze phenomenon" means that, even though the hue is good in a room and under a room light that are not in direct sunlight, under direct sunlight or under transparent glass through direct sunlight, in addition to the originally colored hue, This is a phenomenon in which visible light in the range of red to yellow is seen to overlap, which deteriorates the image of quality in terms of appearance of the molded product and reduces the commercial value. Of course, this bronze phenomenon and metamerism are different phenomena. Moreover, up to the present, no research has been conducted to solve this bronze phenomenon.

<Means for Solving Problems> As a result of earnest research on such problems, the present inventors have found that
Conjugated diene monomer within the specific particle size range consists of a graft polymer obtained by polymerizing rubber and monomer in an amount of less than 50% by weight, and specifies the weight average particle size of the rubber particles as well as the specific particle size range. The present inventors have found that a graft polymer having a rubber particle content of less than a certain value has excellent impact resistance inherent to the graft polymer and does not cause a bronze phenomenon, and has reached the present invention.

Even more surprisingly, the rubber particles having a specific particle diameter of less than a certain value in the present invention are conventionally considered to be the most important particles for imparting impact properties in the rubber reinforced resin.

That is, in the first aspect of the present invention, the conjugated diene monomer is less than 50% by weight as a rubber component, and 95% of the particles are contained.
Rubber (a) whose weight% is within the range of 0.05 to 0.6 μm
A graft polymer obtained by polymerizing one or more monomers (b) selected from the group consisting of aromatic vinyl, unsaturated nitrile and other vinyl monomers copolymerizable with them in the presence of , The weight average particle diameter of all rubber particles is 0.20 to 0.
A graft polymer which does not cause the bronzing phenomenon in a colored molded article, characterized in that the total amount of rubber particles in the range of 0.25 to 0.35 μm is less than 20% by weight based on the total weight of rubber. It is provided.

Further, the second invention of the present invention is selected from the group consisting of 10 to 100% by weight of such a graft polymer (A), aromatic vinyl, unsaturated nitrile and other vinyl monomers copolymerizable therewith. Composition comprising 90 to 0% by weight of (co) polymer (B) obtained by polymerizing one or more monomers (b)
Disclosed is a resin composition containing 0.05 to 10 parts by weight of a colorant per 100 parts by weight, which has an excellent balance of impact resistance and workability and does not cause a bronzing phenomenon.

The present invention will be described in detail below.

The rubber used in the present invention is a rubber in which the content of the conjugated diene monomer is less than 50% by weight, and ethylene-propylene (or butene) copolymer, dicyclopentadiene, ethylidene norbornene, 1,4- Ethylene-propylene (or butene) copolymerized with non-conjugated dienes such as hexadiene, 1,4-cycloheptadiene and 1,5-cyclooctadiene
-Ethylene-alpha olefin rubber (i) such as non-conjugated diene copolymer, homopolymer such as methyl acrylate, ethyl acrylate, butyl acrylate, propyl acrylate, etc., other copolymerization such as butadiene, styrene, acrylonitrile, etc. Acrylic ester rubber (ii) such as a copolymer obtained by copolymerizing a hydrophilic compound, chlorinated polyethylene (iii), ethylene-vinyl acetate copolymer (iv), and the like, and one or more kinds thereof should be used. You can Hereinafter, these rubbers are referred to as non-conjugated diene rubbers. Of these,
Particularly, acrylic acid ester rubber is preferable.

95% by weight or more of the rubber particles have a particle size of 0.05 to 0.6μ.
A non-conjugated diene rubber within the range of m is used. If many rubber particles are less than 0.05 μm, the mechanical properties are inferior, and if more than 0.6 μm, not only the mechanical properties but also the optical properties (gloss) are inferior, which is not preferable.

Examples of the aromatic vinyl constituting the graft polymer (A) include styrene, α-methylstyrene, P-methylstyrene, t-butylstyrene, dimethylstyrene and the like, and one kind or two or more kinds can be used. Particularly preferred is styrene.

Examples of the unsaturated nitrile include acrylonitrile, methacrylonitrile and the like, and one kind or two or more kinds can be used. Acrylonitrile is particularly preferable.

Examples of other vinyl monomers copolymerizable with aromatic vinyl or unsaturated nitrile include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride and anhydrides thereof, and methyl (meth) acrylate. Unsaturated carboxylic acid alkyl ester such as ethyl (meth) acrylate and butyl (meth) acrylate, maleimide,
Maleimide compounds such as methylmaleimide, ethylmaleimide, N-phenylmaleimide, acrylamide,
An amide compound such as methacrylamide is exemplified, and one kind or two or more kinds can be used.

The composition ratio of the non-conjugated diene rubber (a) and the monomer (b) used for graft polymerization is not particularly limited, but generally 5 to 90 parts by weight of the non-conjugated diene rubber from the viewpoint of physical property balance. Parts, 95 to 10 parts by weight of monomer.

Further, the monomer (b) to be subjected to the graft polymerization is one or more monomers consisting of the above-mentioned aromatic vinyl, unsaturated nitrile and other vinyl monomers copolymerizable therewith,
The ratio of each monomer in the monomer (b) is not particularly limited, but from the viewpoint of the physical properties of the graft polymer and the resin composition, the aromatic vinyl and the unsaturated nitrile and / or another monomer are mixed. A combination is preferable, and a monomer composed of 50 to 95% by weight of aromatic vinyl and 5 to 50% by weight of unsaturated nitrile and / or another monomer is particularly preferable.

In the graft polymer of the present invention, not only the distribution of the non-conjugated diene rubber particles is limited, but also the limitation of the weight average particle diameter and the presence of specific particles are positively excluded.

The weight average particle diameter is 0.20 to 0.45 μm. The target particles for calculating the weight average particle diameter cover the entire distribution of rubber particles.

When the weight average particle size is less than 0.20 μm or exceeds 0.45 μm,
Impact resistance, processability in graft polymers and compositions,
It is not preferable because the balance of rigidity and gloss becomes poor.

Further, in the present invention, the weight of all rubber particles in the range of 0.25 to 0.35 μm is limited to less than 20% by weight based on the total weight of rubber contained in the graft polymer.

The weight of all rubber particles within the range of 0.25 to 0.35 μm is 20% by weight based on the weight of particles contained in the graft polymer.
If it becomes the above, the solution of the bronze phenomenon which is the objective of the present invention cannot be achieved. Especially from the aspect of preventing bronze phenomenon,
It is preferred that the total rubber particles within the range of 0.35 μm be less than 5% by weight.

Examples of the method for producing the graft polymer include known polymerization methods such as emulsion polymerization method, solution polymerization method, bulk polymerization method, suspension polymerization method and combinations thereof.

Distribution of rubber particles (0.05-0.6 μm for 95% by weight or more), weight-average particle size (0.20-0.45 μm) and specific particle size (0.
25 to 0.35 μm) Graft polymerization using a non-conjugated diene rubber that satisfies all three conditions of exclusion can obtain the graft polymer intended by the present invention, but has a narrow particle size distribution satisfying such conditions. A method of performing graft polymerization on a non-conjugated diene rubber obtained by mixing two or more non-conjugated diene rubbers having different particle sizes, rather than starting from the production of a single latex, or a non-conjugated particle having a different particle size It is more economical to obtain the graft polymer defined in the present invention by a method of mixing two or more kinds of graft polymers obtained by independently performing graft polymerization using a diene rubber.

The second invention of the present application is a rubber-reinforced material in which the bronzing phenomenon composed of the above-mentioned graft polymer (A), copolymer (B) and colorant (C) is solved and which has an excellent balance of impact resistance and processability. It relates to a resin composition.

Examples of the aromatic vinyl constituting the copolymer (B) include styrene, α-methylstyrene, P-methylstyrene, t-
Butyl styrene, dimethyl styrene, etc. are mentioned, and 1 type (s) or 2 or more types can be used. Especially styrene or α
-Methylstyrene is preferred.

Examples of the unsaturated nitrile include acrylonitrile, methacrylonitrile and the like, and one kind or two or more kinds can be used. Acrylonitrile is particularly preferable.

Examples of other vinyl monomers copolymerizable with aromatic vinyl or unsaturated nitrile include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride and anhydrides thereof, and methyl (meth) acrylate. Unsaturated carboxylic acid alkyl ester such as ethyl (meth) acrylate and butyl (meth) acrylate, maleimide,
Maleimide compounds such as methylmaleimide, ethylmaleimide, N-phenylmaleimide, acrylamide,
An amide compound such as methacrylamide is exemplified, and one kind or two or more kinds can be used.

The monomer constituting the (co) polymer (B) is one or more monomers composed of the above-mentioned aromatic vinyl, unsaturated nitrile and other vinyl monomers copolymerizable therewith, The proportion of each monomer in the monomer (b) is not particularly limited, but a combination of an aromatic vinyl with an unsaturated nitrile and / or another monomer is preferable from the viewpoint of the physical properties of the resin composition, and particularly a fragrance. Group vinyl 50-95% by weight with unsaturated nitrile and /
Alternatively, it is preferably a monomer composed of 5 to 50% by weight of another monomer.

Furthermore, although the intrinsic viscosity of the (co) polymer (B) is not particularly limited, the intrinsic viscosity (30 ° C., dimethylformamide) is preferably 0.30 to 1.30 from the viewpoint of the physical properties of the composition.

As the method for producing the (co) polymer (B), an emulsion polymerization method,
Known polymerization methods such as a solution polymerization method, a bulk polymerization method, a suspension polymerization method and a combination thereof can be mentioned.

The (co) polymer (B) may be blended in an amount of 0 to 90% by weight based on the total weight of the graft polymer (A) and the (co) polymer (B). If it exceeds 90% by weight, the impact resistance of the final composition is poor, which is not preferable. It is preferably 10 to 80% by weight. Particularly, the content of non-conjugated diene rubber in the final composition is 5 to 40% by weight.
It is preferable to mix them so that

As the colorant (C) which is an essential component in the second invention, anthraquinone-based, indanthrene-based, quinonephthalone-based, perinone-based dyes, and further azo-based, phthalocyanine-based, slene-based, dyed lake, and other organic dyes are used. Pigments,
Inorganic pigments such as oxide-based, molybdate chromate-based, selenide sulfide-based, and ferrocyanide-based are listed, and one or more kinds of them can be used.

The content of the colorant is 0.05 to 100 parts by weight of a composition comprising 10 to 100% by weight of a graft polymer and 90 to 0% by weight of a copolymer.
~ 10 parts by weight.

In addition, in the graft polymer and the rubber-reinforced resin composition, not only a colorant but also a known additive such as a plasticizer, an antioxidant, an antistatic agent, an ultraviolet absorber, a flame retardant, a lubricant, and a filler is blended. be able to.

The present invention will be specifically described below with reference to examples.

[Production Method of Graft Polymers A-1 to A-15] In the composition shown in Tables -1 to 3, non-conjugated diene rubber latex, water and an initiator were charged in a nitrogen-substituted 3L glass reactor to prepare a system of 65 Raise to ℃. To this, a monomer mixture containing a chain transfer agent and an emulsifier solution were continuously added over 3 hours. After the addition of the monomer was completed, the reaction was completed by aging it at 68 ° C. for 2 hours.

[Production Method of Copolymers B-1 to B-4] In the composition shown in Table 4, 10% by weight of a monomer mixture containing a chain transfer agent in a nitrogen-substituted 3L glass reactor and 20% by weight of an emulsifier solution. Then, water and an initiator are charged, the temperature is raised to 65 ° C., and aging is performed for 30 minutes. Further, the remaining monomer mixture and the remaining emulsifier solution were continuously added over 4 hours. afterwards
The reaction was completed by aging at 68 ° C for 2 hours.

[Examples] The graft polymers shown in Tables -1 to 3 and the copolymers shown in Table 4 were mixed in the proportions shown in Tables -5 to 6, and 4,4-butylidene-bis- was added as an antioxidant. Add 0.3 parts by weight of 3-methyl-6-tertiary butylphenol, salt out with calcium chloride, and filter through a process of filtration, washing with water, dehydration and drying to obtain a powder having a non-diene rubber content of about 18% by weight. Obtained.

To 100 parts by weight of the obtained powder, 1 part by weight of ethylenebisstearoamide as a lubricant and a colorant described below were added, and the mixture was kneaded and granulated with a Banbury mixer to obtain colored pellets.

200 mm x 100 mm from the obtained colored pellets with an injection molding machine
A colored molded product of a flat plate of 3 mm was prepared, and the bronzing phenomenon was visually evaluated in a room under direct sunlight through transparent glass.

The results are shown in Tables 6-7.

Incidentally, it was confirmed by a spectrophotometer that none of the molded products caused metameriz.

Furthermore, a test piece was prepared from the obtained black A pellets by an injection molding machine, and the Izod impact strength with notch (1/4 ″, 23
° C.) and processability ^{(210 ℃, 30kg / cm 2} ) was measured. Then, when the product of the present invention and the product of interest were compared with those having the same or similar weight average particle diameters, it was confirmed that the product of the present invention was excellent in the balance of impact strength-workability.

<Effects of the Invention> As defined in the present invention, the particle distribution of the non-conjugated diene rubber in the graft polymer is colored in any color by limiting the weight average particle size and excluding the specific particle size (less than 20% by weight). It is possible to provide an excellent graft polymer that does not cause the bronzing phenomenon even when it is treated.

Furthermore, it is possible to provide a colored composition which does not cause the bronzing phenomenon, which is composed of the specified graft polymer, copolymer and colorant, and which has an excellent impact resistance-processability balance.

Claims (4)

[Claims] 1. A rubber component containing a conjugated diene monomer in an amount of less than 50% by weight, and 95% by weight or more of particles of 0.05 to 0.6 μm.
in the presence of rubber (a) in the range of m, aromatic vinyl,
A weight average particle of all rubber particles, comprising a graft polymer obtained by polymerizing one or more monomers (b) selected from the group consisting of unsaturated nitriles and other vinyl monomers copolymerizable with them. The diameter is 0.20 to 0.45 μm, and further 0.
A graft polymer characterized in that the total amount of rubber particles within the range of 25 to 0.35 μm is less than 20% by weight based on the total weight of rubber. 2. The graft polymer according to claim 1, wherein the total amount of the rubber particles within the range of 0.25 to 0.35 μm is less than 5% by weight based on the total weight of the rubber. 3. A rubber component containing less than 50% by weight of a conjugated diene monomer, and 95% by weight or more of particles is 0.05 to 0.6 μm.
in the presence of rubber (a) in the range of m, aromatic vinyl,
A weight average particle of all rubber particles, which comprises a graft polymer obtained by polymerizing one or more monomers (b) selected from the group consisting of unsaturated nitriles and other vinyl monomers copolymerizable with them. The diameter is 0.20 to 0.45 μm, and further 0.
The total amount of rubber particles within the range of 25 to 0.35 μm is less than 20% by weight, based on the total weight of rubber, 10 to 100% by weight of the graft polymer (A), aromatic vinyl and unsaturated nitrile. And a composition comprising 90 to 0% by weight of a (co) polymer (B) obtained by polymerizing one or more monomers (b) selected from the group consisting of other vinyl monomers copolymerizable therewith A rubber-reinforced resin composition comprising 0.05 to 10 parts by weight of a colorant per 100 parts by weight of the product. 4. The rubber-reinforced resin composition according to claim 3, wherein the total amount of the rubber particles in the range of 0.25 to 0.35 μm is less than 5% by weight based on the total weight of the rubber.