JPS6079057A - Thermoplastic resin composition having excellent resistance to heat and impact - Google Patents

Abstract

PURPOSE:To provide the titled compsn. having excellent flow processability and resistance to heat and impact, consisting of a specified copolymer and an acrylate ester graft copolymer. CONSTITUTION:10-1,000pts.wt. mixture consisting of 60-100wt% methyl methacrylate and/or styrene and 0-40wt% other copolymerizable vinyl monomer is polymerized in the presence of 100pts.wt. cross-linked acrylate ester copolymer composed of 50-99.9wt% C1-8 alkyl acrylate, 0-40wt% other copolymerizable monomer and 0.1-10wt% copolymerizable crosslinking monomer, to obtain an acrylate ester graft copolymer (B). 1-99wt% copolymer (A) composed of 40- 89wt% methyl methacrylate, 1-20wt% alpha-methylstyrene and 5-20wt% maleic anhydride is mixed with 99-1wt% component B.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermoplastic resin having excellent heat resistance and impact resistance. [This invention relates to a thermoplastic resin composition with excellent heat resistance and impact resistance, which is composed of a copolymer consisting of [7] and an acrylic acid ester graft copolymer.

Until now, as a method to obtain thermoplastic resins with excellent heat resistance and impact resistance, graft copolymers, which are made by graft copolymerizing styrene or acrylonitrile to diene rubber, have been used.
A method of mixing a terpolymer consisting of α-methylstyrene, methyl methacrylate, and acrylonitrile (Japanese Patent Publication No. 70145/1982) or a method of mixing a polycarbonate resin and a diene rubber (Japanese Patent Publication No. 38/1982)
No. 5225) and the like have been proposed. However, these methods have problems such as difficulty in achieving a balance between heat resistance and impact resistance, and in the case of mixtures of polycarbonate and diene rubber, flow processability is significantly reduced.
The reality is that a material that has both heat resistance and impact resistance has not yet been developed.

As a result of intensive studies on thermoplastic resin compositions with good flow processability, heat resistance, and impact resistance, the present inventors found that a resin composition of a polymer having a specific composition and structure sufficiently achieved the intended purpose. The present invention was achieved by discovering the following.

The gist of the present invention is that methyl methacrylate 40
A copolymer obtained by polymerizing a monomer mixture consisting of ~89% by weight, α-methylstyrene 1-20%, styrene 5-20% and maleic anhydride 5-20% by weight [ 131 to 99% by weight, (a) 50 to 999% of acrylic acid alkyl esters whose alkyl groups have 1 to 8 carbon atoms, 0 to 40% by weight of other copolymerizable vinyl monomers, and copolymerization. (b) methyl methacrylate or 10 to 1000 parts by weight of a monomer or a mixture thereof consisting of 60 to 100% by weight of at least one monomer selected from styrene and 0 to 40% by weight of another vinyl monomer copolymerizable with this monomer. Acrylic acid ester graft copolymer obtained by polymerization [■] 1 to 99
It is a thermoplastic resin composition with excellent heat resistance and impact resistance, with a low weight percentage.

The composition of the present invention is characterized by the above-mentioned methyl methacrylate, α
- The synergistic effect of the copolymer of methylstyrene, styrene, and maleic anhydride [1] and the acrylic acid ester graft copolymer [11] provides a well-balanced property in heat resistance, impact resistance, and flow processability. It is capable of exhibiting excellent properties.

The crosslinked acrylic acid ester copolymer [1] referred to in the present invention is 50 to 98% by weight of methyl methacrylate, 1 to 2% α-methylstyrene, 5 to 20% by weight of styrene, and 5 to 20% by weight of maleic anhydride. It is a polymerized monomer mixture consisting of the following, and has the effect of imparting heat resistance and flow processability to the final resin composition. In addition, the proportions of each constituent unit of methyl methacrylate, α-methylstyrene, styrene, and maleic anhydride in copolymer [1] are determined by the heat resistance, weather resistance, polymerization rate, and flow processability of copolymer [1]. If the monomer component with a deviation of φ is outside the above range, problems such as poor heat resistance and weather resistance and extremely poor productivity will occur. The blending ratio of copolymer [I] is 1 to 9 in the total resin composition.
9 layers, more preferably 10 to 90 layers, 1
If it is less than the overlapping part, heat resistance and flow processability tend to be poor, and if it exceeds 99% by weight, impact resistance tends to be poor.

Copolymerization@J[I] can be produced by a commonly used polymerization method such as bulk polymerization or solution polymerization using the above monomer mixture using a radical polymerization initiator.

Further, if necessary, it is also possible to add other copolymerizable *i groups as a fourth component in an amount of 10% by weight or less.

The acrylic acid ester-based graft copolymer [13 has the effect of imparting impact resistance to the target resin composition, and is present in an amount of 1 to 99 weight percent in the entire resin composition, more preferably 10 ~90% by weight. If it is less than 1 layer, the impact resistance will be poor, and if it exceeds 99 layers, the heat resistance will be poor, both of which are not preferred.

Acrylic ester-based graft copolymer used in the present invention [11)? When dispersed in a resin composition, it is necessary to limit the particle size of the acrylic acid ester graft copolymer [11] in order to achieve a good balance between appearance characteristics and impact resistance, and usually α05 to [1,5 μmz Lv
Preferably, the range of αo8 to α−2 μm is necessary.

The acrylic ester-based kraft copolymer [■] is produced in two steps. The first step (a) is an acrylic acid alkyl ester in which the alkyl group has 1 to 8 carbon atoms, 50 to 9
99-weight 11-1, other vinyl monomers copolymerizable with this, 0 to 40 weight ratio, and 2 carbon-carbon double bonds in the molecule.
A monomer mixture consisting of 1 to 103iii% of crosslinkable monomers α1 or more is copolymerized, and acrylic acid alkyl esters include butyl acrylate, 2-ethylhexyl acrylate, E-1tX, etc. preferable. Other vinyl monomers that can be copolymerized with this include aromatic vinyl monomers represented by styrene, acrylonitrile,
Examples include methyl methacrylate, butyl methacrylate, acrylic acid, methacrylic acid, and maleic acid. Copolymerizable crosslinkable monomers include ethylene glycol dimethacrylate, 1,3-butylene dimethacrylate, ethylene glycol diacrylate, trimethylol, propane triacrylate, allyl methacrylate, allyl cinnamate, divinylbenzene, triallylucia. Nurate, triallyl isocyanurate, allylturbate, diallyl phthalate, diallyl maleate, etc. are preferred, and preferred are 1,5-butylene dimethacrylate, divinylbenzene, allyl acrylate, triallyl isocyanurate, allyl cinnamate. They can be grown alone or used in combination.

In the second step (b), in the presence of the crosslinked acrylic ester copolymer obtained in the first step, methyl methacrylate or styrene is copolymerized with 60% by weight or more of methyl methacrylate and styrene. Other vinyl monomers 4
Copolymerizable vinyl monomers include aromatic vinyl other than styrene, ethyl methacrylate, acrylonitrile, methacrylic acid, and acrylic acid. , ethylene glycol dimethacrylate and alkyl group have 1 to 1 carbon atoms
The acrylic acid alkyl ester of No. 8 is opened. More preferred are acrylonitrile, acrylic acid alkyl esters having 1 to 8 carbon atoms, acrylic acid, methacrylic acid, ethylene glycol, diacrylate, and the like. However, among these monomer groups, when using crosslinking monomers,
Attention should be paid to the amount of addition and the amount of coagulation. For example, in the polymerization operation, a predominant amount of methyl methacrylate,
Alternatively, it is also possible to separate the styrene, the monomer, or a mixture thereof into a part to which the crosslinking monomer is added and a part to which it is not added, and polymerize them separately.

Each stage constituting the acrylic acid ester graft copolymer [■], namely the first stage (&) and the second stage (b
) does not need to have a homogeneous composition at each stage, and it is possible to completely change the composition within the patent application.

9 in acrylic acid ester graft copolymer [11]
Then, the second stage of φ) is polymerized in the presence of 100 parts by weight of the first stage of (a), the second stage of 10 to 1000 parts by weight,
It should preferably range from 20 to 500 parts by weight.

Outside these ranges, problems arise such as an imbalance between impact resistance and appearance, low impact resistance, and poor productivity.

In addition, in order to adjust the molecule t as necessary, a degree of polymerization regulator such as mercaptan may be used in the monomers constituting all of the first stage in (a) and the second stage in (b). It is possible. Examples of the polymerization degree regulator that can be used include alkyl mercaptans, thioglycolic acid and its esters, β-mercaptopropionic acid and its esters, and aromatic mercaptans such as thiophenol and thiocresol.

In order to produce the resin composition of the present invention having excellent heat resistance and impact resistance, it is particularly preferable to use the acrylic acid ester graft copolymer [1] by emulsion polymerization. This will be explained using an example of the polymerization method.

After adding deionized water, a polymerization initiator, and an emulsifier to the reaction vessel, the monomer mixture constituting the first stage of (a) is polymerized, and then the monomers constituting the second stage of (b) are polymerized. The mixture is completely polymerized. The polymerization temperature is 30 to 120°C, preferably 50 to 100°C. The polymerization time varies depending on the type and amount of the polymerization initiator and emulsifier, the polymerization temperature, etc., but it usually depends on each polymerization stage, (a) and cb) for 0.5 to 7 hours, respectively.

The ratio of polymer to water is preferably monomer/water=1720 to 1/.

The polymerization initiator and emulsifier can be added to either the aqueous phase, the monomer phase, the body phase, or both.

The method of charging each monomer in the polymerization step (&) and (b) can be carried out all at once or in divided portions, but the divided charging method is more preferable from the viewpoint of polymerization heat generation and the like.

The emulsifier is not particularly limited as long as it is a commonly used emulsifier; examples thereof include long-chain alkyl carboxylates, sulfosuccinic acid alkyl ester salts, alkylbenzene sulfonates, and the like.

There is no need to particularly limit the type of polymerization initiator, and commonly used inorganic initiators such as persulfates and perborates can be used alone or in combination with sulfites and thiosulfates as redox initiators. You can also do it. Redox initiation systems such as organic hydroperoxide-ferrous salts, organic hydroperoxide-lysium formaldehyde sulfoxylate, benzoyl peroxide, azobisisobutyronitrile, and the like can also be used.

The polymer latex obtained by the emulsion polymerization method is coagulated by a known method.

The composition of the present invention is composed of a copolymer [I] and an acrylic acid ester graft copolymer [■],
Depending on the purpose of use, at least one resin selected from other methacrylic resins, polycarbonate, A8 resin, methyl methacrylate-styrene copolymer, polystyrene, polyester (polyethylene terephthalate, polybutylene terephthalate), and nylon. (2)] can also be added to the composition by 98 weight lee. For example, when extremely good weather resistance is required, methacrylic resins and polyethylene terephthalate resins are suitable, and when high flow processability is required, polystyrene, A
Sm fat and methyl methacrylate-styrene copolymer are used.

Furthermore, in the composition of the present invention, if necessary,
Stabilizers, lubricants, plasticizers, dyes and pigments, fillers, etc. are added as appropriate and mixed using a V-type blender, Henschel mixer, etc., and then mixed at 150 to 600°C using a mixing roll, screw type extruder, etc. Melt mix.

By molding the obtained composition using an extrusion molding machine, an injection molding machine, etc., a molded product with excellent heat resistance and impact resistance can be obtained, so it can be used for vehicle exterior parts, solar system equipment parts, and It is useful for applications such as electrical parts.

In the following examples, ``chi'' means the total weight %.

Examples 1 to 4, Comparative Examples 1 to 6 Copolymer (manufactured in 13) Methyl methacrylate 14 kg, α-methylstyrene 1.
o kg, styrene 2.5 kg, maleic anhydride 2,
5 kg of t-dodecyl mercaptan and 60 f of t-dodecyl mercaptan were placed in a SUS reaction vessel equipped with a cooling tube, a thermometer, and a stirrer, and heated while stirring until the internal temperature reached 75.
2 tJ t'ff of azobisisobutyronitrile was added at 95° C., the internal temperature was kept at 95° C. for 15 minutes, and then cooled to obtain a partially polymerized product in the form of silalag.

Bis(
3,s,s-trimethylhexanoyl)peroxide 3
00 f, JP-504 (&:,?,)j as a release agent
After dissolving 1.121F manufactured by Johoku Kagaku@ and adding stearic acid monoglyceride 101111F'i as a mold release agent, it was molded into several sets of cells formed by two tempered glass plates facing each other at a distance of 61 m with a polyvinyl chloride gasket interposed therebetween. The composition was injected and immersed in warm water at 80°C to polymerize and harden.

Thereafter, it was treated in an air heating oven at 130°C for 2 hours. After cooling, the cell metal was removed, and a resin plate with a thickness of approximately 6 mm was cut and crushed using a crusher to form pellets.

Production of acrylic acid ester-based graft copolymer [■] (a) First step 1) 200 f, ferrous sulfate [LOllF, disodium ethylenediaminetetraacetate (hereinafter referred to as ED T
In a 50 t SU8 reaction vessel containing 25 g of sodium formaldehyde sulfoquiminate (abbreviated as A-2Na), 7% butyl acrylate 9a, 1.0% allyl methacrylate, and tert-butyl hydroperoxide were added. After charging 9f of a 3% mixture of IllL (hereinafter abbreviated as t-BH) and replacing the oxygen in the reaction vessel with nitrogen, polymerization was carried out at 70°C for 2 hours with stirring, and then TK-1 Added 1 liter of a 5% aqueous solution of

Thereafter, 9 was continuously added to the mixture 7 having the same composition as that previously polymerized over a period of 2 hours, and after the addition was completed, the polymerization was continued for another 2 hours.

(1)) Second stage 1 kg of 5% TK-1 aqueous solution was added to the same reaction vessel where the first stage was completed, and under the same 70°C conditions as the first stage,
Methyl methacrylate 9&7%, methyl acrylate 3%,
6 kg of a mixture of 115% normal dodecyl mercaptan (hereinafter abbreviated as n-Dm) and 2% 7-BHl' was added continuously over 90 minutes, and after the addition was completed, polymerization was continued for an additional hour.

The latex particle diameter calculated by absorbance method is α12μm
Met.

The latex of the obtained graft copolymer [■] has α2
It was coagulated with 5% sulfuric acid water at latex/water = 172.50°C. The obtained slurry-like white polymer was
After washing with water and dehydrating with o times the amount of DW, it was dried at 75° C. for 36 hours.

Next, copolymer [I] obtained above, acrylic acid ester graft copolymer [11) and other resin [1[1]
) were mixed using a Henschel mixer in the proportions shown in Table 1, and then using a screw extruder, the cylinder temperature was 20°C.
The mixture was melt-kneaded at 0 to 270°C and a die temperature of 260°C to form pellets. This was injection molded under the following conditions, and the evaluation results shown in Table 1 were obtained from the obtained test pieces.

Injection molding machine: Newly manufactured by Nippon Steel, V-17-65 type screw complete automatic injection molding machine Injection molding conditions Niji cylinder temperature change Injection pressure 700 to 9/lri, mold temperature 52℃ Test piece size: 110 x 110 x 2 (Thickness) m70x12.5
X6.2 (thickness) IgI treatment ~ 6 The copolymer (1) used was exactly the same as in Examples 1 to 4, and the acrylic acid ester graft copolymer [1 [] It was produced in exactly the same manner as in Examples 1 to 4, except that the amount of 7-mer mixture used during production was changed from 9 to 1.5 kg for tt-3. Using that material, a blend was formed in the proportions shown in Table 1.

The obtained pellets were evaluated in the same manner as in Examples 1 to 4, and the results shown in Table 1 were obtained.

Examples 7 to 11, Comparative Examples 4 to 5 The proportions of the copolymer [l] and the acrylic acid ester graft copolymer [■] used in Examples 1 to 4, and the ratio of the copolymer resin [[11]] The types and proportions were changed as shown in Table 2, and the evaluation was performed in the same manner as in Example 1, and the results shown in Table 2 were obtained.

Procedural Amendment Written by December 27, 1949, Commissioner of the Patent Office Gakudono Shiga1, Indication of the case: Zuhato - Patent Application No. 188024/1982, Title of the invention: Thermoplastic resin composition with excellent heat resistance and impact resistance Thing 3
, Relationship with the person making the amendment Patent applicant 2-3-19 Kyobashi, Chuo-ku, Tokyo (603) Akio Kawasaki 4, President, Mitsubishi Rayon Co., Ltd. Embedded 2-3 Kyobashi, Chuo-ku, Tokyo No. 19 Mitsubishi Rayon Co., Ltd. [De-en 7. - Contents of amendments and corrections (1) "Crosslinked acrylic ester copolymer (1) J't-r copolymer [■]" described on page 5, lines 11-12 of the specification
”.

Claims (1)

[Claims] 1. A monomer mixture consisting of 40-89% by weight of methyl methacrylate, 1-20% of α-methylstyrene, 5-20% by weight of styrene, and 5-20% by weight of maleic anhydride. Copolymer [I] obtained by polymerization 1 to 99 weight ratio, overlapping part 50 to 99.93 fi% of an acrylic acid alkyl ester having an alkyl group of 1 to 8 carbon atoms, and other copolymerizable vinyl Crosslinked acrylic acid ester copolymer 10 obtained by polymerizing a monomer mixture consisting of 0 to 40% crosslinkable monomer α1 to 10%
(b) at least one monomer selected from methyl methacrylate or styrene 60 to 100 parts by weight - Jilqb
Acrylic acid ester graft copolymer obtained by polymerizing 10 to 1000 parts by weight of a monomer or a mixture thereof consisting of this and 0 to 40% by weight of another copolymerizable vinyl monomer [ ■〕1～99
A thermoplastic resin composition with excellent heat resistance and impact resistance consisting of % by weight. 2. At least one selected from methacrylic resin, polycarbonate, AS resin, methyl methacrylate-styrene copolymer, polystyrene, polyester, and nylon.
A thermoplastic resin composition having excellent heat resistance and impact resistance as claimed in claim 1, which can be used by adding 98% by weight or less of a seed resin.