JPS6069151A - Thermoplastic resin composition with excellent heat resistance and impact resistance - Google Patents

Abstract

PURPOSE:To provide a thermoplastic resin compsn. having good flow processability and excellent resistance to heat and impact, consisting of a specified copolymer and a specified multi-layer structure copolymer. CONSTITUTION:The titled compsn. consists of 1-99% copolymer (A) composed of 50-98% methyl methacrylate, 1-25% alpha-methylstyrene and 1-25% maleic anhydride and 99-1% multi-layer structure acrylic copolymer (B) composed of an outermost layer obtd. by (co)polymerizing 100pts. 1-18C alkyl acrylate, etc. and an inner layer composed of a copolymer obtd. by a step (a) of (co)polymerizing 2.5-500pts. methyl methacrylate, etc., a step (b) of polymerizing 25-950pts. monomer mixture consisting of 95-99.9% 1-8C alkyl acrylate, etc. and 5-0.1% monomer contg. at least two carbon-to-carbon double bonds and a step (c) of (co)polymerizing 50-10,000pts. methyl methacrylate, etc. in the presence of the polymers formed in the steps (a) and (b), and having a composition satisfying the ratio of a/b of 1/1-1/20 and (a+b)/c of 1/0.2-1/10.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermoplastic resin with excellent heat resistance and impact resistance. The present invention relates to a thermoplastic resin composition having excellent heat resistance and impact resistance, which is made of a copolymer of

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. 70143/1983) or a method of mixing a polycarbonate resin and a diene rubber (Japanese Patent Publication No. 38/1989)
No. 5225) and the like have been proposed. However, with these methods, it is difficult to balance heat resistance and impact resistance, and in the case of mixtures of polycarbonate and diene rubber, there are problems such as a marked decrease in flow processability.
The reality is that a material that has both heat resistance and impact resistance has not yet been developed.

As a result of examining the amount of iron in heat-resistant and impact-resistant thermoplastic resin compositions with good flow processability, the present inventors found that resin compositions of polymers with a specific composition and structure were sufficient for the intended purpose. The present invention was achieved by discovering the following.

The gist of the present invention is that methyl tutaacrylate 50
A copolymer [I] obtained by polymerizing a monomer mixture consisting of ~98 weight units, 1 to 25 weight units of α-methylstyrene, and 1 to 25 weight units of maleic anhydride [I] 1 to 99 weight units;
The outermost layer contains 60 to 100% by weight of an acrylic acid alkyl ester having an alkyl group having 1 to 8 carbon atoms, 0 to 40% by weight of another vinyl monomer that can be copolymerized therewith, and 2% by weight between carbon atoms in the molecule. A product obtained by polymerizing 100 parts by weight of a monomer consisting of 0 to 5 parts by weight of a monomer having two or more double bonds, or a mixture thereof, in which (A) 60 to 100% by weight of methyl methacrylate; Other vinyl monomers that can be copolymerized with this: 0 to 40% by weight, and monomers with 2 or more carbon-carbon double bonds in the molecule: 0
~25~ of monomers or mixtures thereof exceeding 10% by weight
The first stage of polymerizing 500 parts by weight, middle) 60 to 999 parts by weight of an acrylic acid alkyl ester whose alkyl group has 1 to 8 carbon atoms, and 0 to 399 parts by weight of other vinyl monomers that can be copolymerized therewith. a second step of polymerizing 25 to 950 parts by weight of a monomer mixture consisting of 0.1 to 5 parts by weight of a monomer having two or more carbon-carbon double bonds in the molecule; (0) the first stage; And in the presence of the polymerized product from the second step, 60 to 100% by weight of methyl methacrylate, 40% by weight of other vinyl monomers that can be copolymerized with this, and a carbon-carbon double bond in the molecule. Monomers having 2 or more 0 to 10
50 to 100 of a monomer or a mixture thereof that exceeds the weight by weight
It is a copolymer obtained by a three-step reaction in the third step of polymerizing 00 parts by weight, and the composition is (A)/(B)=
1/1 to 1/20 and ((A)+(9))/(
0) = 170.2 to 1/10 A thermoplastic resin composition with excellent heat resistance and impact resistance consisting of a multi-layered acrylic copolymer [■] with a weight ratio of 1 to 99,
It's in things.

The composition of the present invention is characterized by the above-mentioned methyl methacrylate, α
- Copolymer of methylstyrene and maleic anhydride [I
] and the multi-structure acrylic copolymer CI+] component, it is possible to exhibit excellent, well-balanced properties in heat resistance, impact resistance, and flow processability.

Copolymer [1F] as used in the present invention refers to 50 to 98% by weight of methyl methacrylate and 1 to 25% by weight of α-methylstyrene.
It has the effect of imparting heat resistance and flow processability to the final resin composition. In addition, the ratio of each constituent unit of methyl methacrylate, α-methylstyrene, and maleic anhydride in the copolymer [1] is determined by the heat resistance, weather resistance, polymerization rate, flow processability, etc. of the copolymer [1]. If any monomer component is outside the above range, problems such as poor heat resistance, poor weather resistance, and extremely poor productivity will occur. The blending ratio of the copolymer CIF is 1 to 99% by weight, preferably 10 to 90% by weight in the entire resin composition,
If the weight ratio is less than 1, the heat resistance and flow processability tend to be poor, and if the weight ratio exceeds 99, the impact resistance tends to be poor.

Copolymer [11] can be produced by a commonly used polymerization method such as bulk polymerization or solution polymerization using the above monomer mixture with a radical polymerization initiator. Further, if necessary, it is also possible to add another copolymerizable monomer having a weight ratio of 10 or less as a fourth component.

The multi-layered acrylic copolymer [■] has the effect of imparting impact resistance to the intended resin composition, and is preferably 1 to 99% by weight in the entire resin composition.
It is 0 to 90% by weight. If it is less than 1 weight ratio, the impact resistance will be poor, and if it exceeds 99 weight ratio, the heat resistance will be poor, both of which are not preferred.

One of the most important features of the composition of the present invention is that the structure of the multi-layered acrylic copolymer [11] is incorporated into the elastomer layer of the polymer mainly composed of alkyl acrylic ester. , a hard resin layer (A) of a polymer whose main component is methyl methacrylate, a soft resin layer (03) of a polymer whose main component is an alkyl acrylate ester, and a hard resin layer (A) of a polymer whose main component is methyl methacrylate. The resin layer has a multilayer structure containing a copolymer composed of three stages.

Multi-structure acrylic copolymer used in the present invention [1[
] in the copolymer [I], it is necessary to limit the particle size of the multilayer acrylic copolymer [11] in order to balance appearance characteristics and impact resistance. 0.005 to 0.45 μm, especially 0.15 to 1
A particle size range of 55 μm is preferred.

In the three different resin structures contained inside the outermost elastomer of the multi-structure acrylic copolymer [I[], the product of the first step (A) is methyl methacrylate 6
0 to 100 weight scale, other vinyl monomers that can be copolymerized with this, 0 to 40 weight scale, and monomers having two or more carbon-carbon double bonds in the molecule 0 to 10 weight scale It is a copolymer of monomers or a mixture thereof. Other copolymerizable vinyl monomers include acrylic acid alkyl esters in which the alkyl group has 1 to 8 carbon atoms, aromatic vinyl monomers represented by styrene, acrylonitrile, ethyl methacrylate, and butyl methacrylate. , acrylic acid, methacrylic acid, maleic acid, etc. Examples of monomers having two or more carbon-carbon double bonds in the molecule include ethylene glycol dimethacrylate, 1,3-butylene dimethacrylate, ethylene glycol diacrylate, trimethylolpropane triacrylate, and allyl methacrylate. - Allyl cinnamate, divinylbenzene triallyl cyanurate, triallyl in cyanurate, allyl turbate, diallyl phthalate, diallyl maleate, etc., preferably 1,3-butylene dimethacrylate, divinylbenzene, allyl acrylate, tri- Examples include allyl in cyanurate and allyl cinnamate.

These can be used alone or in combination.

In the second step), in the presence of the copolymer obtained in the first step, an alkyl acrylic ester having an alkyl group having 1 to B carbon atoms, preferably a butyl acrylate, an acrylic acid Other vinyl monomers D that can be copolymerized with -2-ethelvexyl 60-999% by weight - 39.9% by weight, monomers having two or more carbon-carbon double bonds in the molecule 0.1-5
It is obtained by polymerizing a monomer mixture consisting of weight ratios.

Examples of vinyl monomers that can be copolymerized with acrylic acid alkyl esters include aromatic vinyl monomers such as styrene, methacrylic acid alkyl esters having an alkyl group of 1 to 4 carbon atoms, and acrylonitrile. Examples of monomers having two or more carbon-carbon double bonds in the molecule include ethylene glycol dimethacrylate, ethylene glycol diacrylate, 1,3-butylene dimethacrylate, trimethylolpropane triacrylate, and pentaerythritol tetraacrylate. , divinylbenzene, triallyl cyanurate, triallyl isocyanurate, allyl cinnamate, methacrylate, allyl turbate, diallyl phthalate, diallyl maleate, etc.
Preferably, methacrylic acid alkyl ester having 1 to 4 carbon atoms, styrene, ethylene glyfur diacrylate,
1.3-butylene dimethacrylate, allyl cinnamate,
Examples include allyl methacrylate.

The product of the third step (0) is a mixture of methyl methacrylate 60-60 in the presence of the copolymers obtained in the first and second steps.
100 weight percent, another vinyl monomer copolymerizable with this monomer 0 to 40 weight percent, and a monomer having two or more carbon-carbon double bonds in the molecule 0 to 10 weight percent. polymer or a mixture thereof. As the vinyl monomer copolymerizable with methyl methacrylate, preferably used are acrylic acid alkyl esters in which the alkyl group has 1 to B carbon atoms, styrene, acrylonitrile, and the like. The monomer having a carbon-carbon double bond in its molecule is not limited to any particular type, but preferably allyl methacrylate, divinylbenzene, ethylene glycol diacrylate, 1,3-butylene dimethacrylate, allyl cinnamate, Allylturbate, triallyl iso7anurate, etc. are used.

The outermost layer of the elastomer, that is, the product of the fourth step (b), contains 60 to 100 weight percent of an acrylic acid alkyl ester whose alkyl group has 1 to 8 carbon atoms and 0 to 100 of other copolymerizable vinyl monomers. 40 weight ratio, and 2 carbon atoms in the molecule
It is a product obtained by polymerizing monomers having 0 to 5 weight percentages of monomers having two or more double bonds, or a mixture thereof. As the acrylic acid alkyl ester, butyl acrylate,
2-ethylhegysyl acrylate is preferred. Other copolymerizable monomers include methacrylic acid alkyl esters having 1 to 4 carbon atoms, styrene, methacrylic acid, acrylonitrile, and the like. 2 carbon-carbon double bonds in the molecule
Preferred examples of the monomer having at least 1 or more are allyl methacrylate, allyl turvate, 1,3-butylene dimethacrylate, and the like.

The products of the first stage, second stage, third stage, and fourth stage of the outermost layer constituting the multi-structure acrylic copolymer [ffl] do not need to have a homogeneous composition at each stage; The proportions can also be changed within the scope of the invention.

In the multi-structure acrylic copolymer [...], the hard first stage product to be contained in the outermost layer, that is, 100 parts by weight of the fourth stage product, is 15 to 500 parts by weight, preferably 5 to 400 parts by weight. parts by weight, the soft second stage product is from 25 to 950 parts by weight, preferably from 50 to 900 parts by weight;
The hard third stage product ranges from 50 to 10,000 parts by weight, preferably from 100 to 500 parts by weight. Also,
The composition ratio of (A), (9), and (0) is (A)/(
B) = 1/1 to 1/20, ((4) + (B) ) /(
0)=1/a2 to 1/10. Outside these ranges, problems such as an imbalance between the impact resistance and heat resistance of the molded product and poor productivity arise.

In addition, for the monomers constituting the products of the fourth stage and each stage of the first, second and third stages, a degree of polymerization regulator such as mercaptan is used to adjust the molecular weight as necessary. It is also possible. As polymerization degree regulators, alkyl mercaptans, thioglycolic acid and its esters,
Examples include aromatic mercaptans such as β-methicaptopropionic acid and its esters, thiophenol, and thiocresol.

In order to produce the methacrylic resin composition of the present invention, it is particularly preferable to use the emulsion polymerization method using a multi-layered acrylic copolymer [111], so an example of the emulsion polymerization method will be described below.

Deionized water and a polymerization initiator emulsifier are added to the reaction vessel, and the monomer mixture constituting the first stage is added thereto to perform polymerization, then the third stage and third stage polymerization are performed, and finally, Perform the fourth stage polymerization.

Polymerization temperature is 30-120°C, preferably 50-100'
It is C. The polymerization time depends on the type of polymerization initiator and emulsifier,
Although it varies depending on the amount thereof, polymerization temperature, etc., it is usually 0.5 to 7 hours at each polymerization stage. The ratio of polymer to water is preferably monomer/water = 1,720 to 1/1.

A polymerization initiator and an emulsifier can be added to either or both of the aqueous phase and the monomer phase.

Each of the monomers in the polymerization steps (A), (9), (C), and (9) can be charged all at once or in parts, but the split charging method is less effective in terms of polymerization heat generation. preferable.

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

The type of polymerization initiator is not particularly limited, but commonly used inorganic initiators such as persulfates and perborates, redox initiators in combination with these and sulfites, organic hydroperoxide-ferrous salts, organic Initiators such as hydroperoxide dosodium formaldehyde sulfoxylate redox initiators, penzoyl peroxide, azobisisobutyronitrile, and the like can also be used.

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

When blending and dispersing the obtained multi-layer structure acrylic copolymer [111] into the copolymer [■], it is preferable to perform melt mixing.

The composition of the present invention is composed of a copolymer CI] and a multilayer acrylic copolymer [''ll], but depending on the purpose of use, it may also contain other methacrylic resins, polycarbonate, As resin, It is also possible to add 98% by weight or less of at least one resin [111] selected from methyl methacrylate-styrene copolymer, polystyrene, polyester (polyethylene terephthalate, polybutylene tin phthalate), and nylon to the composition. For example, When extremely good weather resistance is required, methacrylic resins and polyethylene terephthalate resins are suitable; when high fluidity is required, polystyrene, As resins and methyl methacrylate-styrene copolymers are suitable. coalescence is 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 melted at 150 to 300°C using a mixing roll, screw type extruder, etc. 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. It is useful for applications such as equipment parts and electrical parts.

In the following examples, the symbol means weight St.

Examples 1 to 4, Comparative Examples 1 to 3 Production of copolymer CD In a SUB reaction vessel equipped with a cooling tube, a thermometer, and a stirring device, 66 kg of methyl methacrylate, 9 kg of α-methylstyrene 19' , maleic anhydride (15K), and t-dodecyl mercaptan (250 ff) were charged, and while stirring, nitrogen gas was blown into the system to drive out the air in the system. After that, it was heated to an internal temperature of 70°C.
- Dimethylvaleronitrile) 200f was added, and the internal temperature was 9.
After maintaining the temperature at 5° C. for 15 minutes, the mixture was cooled to room temperature to obtain a viscous partial polymer.

For 100 Y of this partial polymer, 400 F of lauroyl peroxide, 500 Y of t-dodecyl mercapta
f, Tinuvin-P (manufactured by Teva Nobu Geigi) 5
0f, JP-504 (manufactured by Johoku Kagaku C Co., Ltd.) 20f
, Add 100 t1 of Mark-329 (manufactured by Adeka Argus Co., Ltd.) and stearic acid monoglyceride 1002, stir thoroughly to dissolve it, and then place two sheets facing each other at an interval of 6 strips with a polyvinyl chloride gasket interposed therebetween. Several sets of cells made of tempered glass plates and equipped with thermocouples,
The partially polymerized product prepared previously was injected and immersed in warm water at 80°C to polymerize and harden. After confirming that the internal temperature of the cell had reached its peak after immersion, polymerization was continued for another 30 minutes, and then the cell was taken out of the warm water and heat-treated in an air heating oven at 130° C. for 2 hours.

After cooling, the cell was removed to obtain a resin plate having a thickness of approximately 61+IIl. This plate-like polymer was cut and crushed into pellet-like products.

Preparation of multi-structure acrylic copolymer [111 (4) First step: Put into a glass-lined reaction vessel with a capacity of 50 mm.
Deionized water 25kII, Sarcosinate L as emulsifier
H (Nikko Chemicals product, hereinafter abbreviated as SLN) 10
f, ferrous sulfate aaasy, disodium ethylenediaminetetraacetate (hereinafter abbreviated as F!DTA-2Na) [
10025f and sodium formaldehyde sulfoxylate (hereinafter abbreviated as EIIF day) 40f,
Next, methyl methacrylate 97, methyl acrylate 1
A mixture of 1,3-butylene dimethacrylate V-11, 2, allyl methacrylate, 15, and cumene hydroperoxide (hereinafter abbreviated as OHP) A was charged in 11 batches, and oxygen in the reaction vessel was added under stirring. After replacing with nitrogen gas, polymerization was carried out at 80° C. for 60 minutes. After that 5LN
Add 500f of O&2 aqueous solution, and further add 60% methyl methacrylate, 30% styrene, butyl acrylate &2
%, 1.5% of 1.3-butylene dimethacrylate and 0.5% of CHP was added at once, and after the addition was completed, polymerization was continued for 90 minutes.

(b) Second stage: In the same container containing 2 kg of the polymer from the first stage, under the same 80°C conditions as the first stage! 3Lll to 55 and 8
Add 500f of an aqueous solution containing 5 parts of FB, then add 85% butyl acrylate and 12.8% methyl methacrylate.
81q7, a mixture consisting of 1.0% allyl methacrylate, 15% 1.4-butanediol cyacrylate, and OHPα7, was added continuously over 180 minutes, and after the addition was completed, polymerization was continued for an additional 180 minutes. .

(0) Third stage The same container containing 10 kg of the copolymer up to the second stage is
SLN 2% aqueous solution 5oor' while kept at 0°C
! i = added, then 5 g of a mixture consisting of 96% methyl methacrylate, 3.5% ethyl acrylate, 0.2% n-octyl mercaptan and OHP a 596 was added continuously over a period of 90 minutes, and after the addition was complete, Polymerization was continued for an additional 60 minutes. The obtained polymer is (A)
/(b)=1/4, ((A)+(B))/(0)=
It was 1/o, s.

(9) In the fourth stage, the same container containing 15 yu of the copolymer from the third stage is heated to 80 yen.
EILN 1% and SF84 while kept at °C.
To a mixture 2 containing 60% of butyl acrylate, 4% of methyl methacrylate, 0.5% of allyl methacrylate, 1.5% of 4-butanediol dimethacrylate and CJHP [16] After addition, polymerization was continued for 120 minutes to obtain a latex-like multi-structure acrylic copolymer consisting of four stages. The latex particle diameter calculated by absorbance method was 0.31 μm.

The obtained multi-structure acrylic copolymer was coagulated with α25% sulfuric acid water at latex/water=1/2.50°C. The obtained slurry-like white polymer was washed with 30 times as much deionized water, dehydrated, and then dried at 75° C. for 36 hours.

Next, the copolymer [I] obtained above, the multilayer acrylic copolymer [■], and other resins ([11] were mixed in the ratio shown in Table 1 using a Henschel mixer, and then Using an extruder, the cylinder temperature is 200℃.
The mixture was melt-kneaded at ~270°C and a Gui 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 test pieces obtained.

Injection molding machine: Manufactured by Japan Steel Works, 7-17-65 type screw complete automatic injection molding machine Injection molding conditions: Cylinder temperature change, injection pressure 700 k
g/Fu2, mold temperature 52 Test piece size: 110 x 110 x 2 m (thickness) 70 x 12
-5
] was produced in exactly the same manner as in Examples 1 to 4, except that the amount of monomer mixture used in the two-step production was changed from 8 kg to 4 kg. Blends were formed in the proportions shown in Table 1 using the raw materials.

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 [I] and the multilayer acrylic copolymer [n] used in Examples 1 to 4, and the resin [llll
] The types and proportions of the samples were changed as shown in Table 2, and the evaluation was carried out in the same manner as in Examples 1 to 4, and the results shown in Table 2 were obtained.

Claims (1)

[Claims] 1. Methyl methacrylate 50 to 98 weight percent, α-methylstyrene 1 to 25 weight percent, and maleic anhydride 1 to 2 weight percent.
Copolymer [I] obtained by polymerizing a monomer mixture consisting of 5% by weight, with a weight ratio of 1 to 99% and an outermost layer having a carbon number of 1 to 8
Acrylic acid alkyl ester having an alkyl group of 60
A Φ-mer consisting of ~100% by weight, 0-40% by weight of other vinyl monomers that can be copolymerized with it, and 0-5% by weight of a monomer having two or more carbon-carbon double bonds in the molecule. Or, 100 parts by weight of the mixture is polymerized, and the inside thereof contains (A) 60 to 100 parts by weight of methyl methacrylate, 0 to 40 parts by weight of other vinyl monomers that can be copolymerized with this, and molecules. Monomer having two or more carbon-carbon double bonds within 0
2.5 of monomers or mixtures thereof consisting of ~10 parts by weight
The first step of polymerizing ~500 parts by weight, 03) acrylic acid alkyl ester whose alkyl group has 1 to 8 carbon atoms 60~
99.9 weight scale, other vinyl monomers that can be copolymerized with this, 0 to 399 weight scale, and monomers having two or more carbon-carbon double bonds in the molecule [1,1 to 5 weight scale] a second step of polymerizing 25 to 950 parts by weight of a monomer mixture consisting of (0) 60 to 100 parts by weight of methyl methacrylate in the presence of the polymers from the first and second stages; Other polymerizable vinyl monomers with 0 to 40 polymers and carbon-carbon double bonds in the molecule? Monomers having 2 or more 0 to 10
50 to 100 of a monomer or a mixture thereof consisting of a weight ratio of 50 to 100
It is a copolymer obtained by a three-step reaction in the third step of polymerizing 00 parts by weight, and the composition ratio is (A)/(9) = 1/1 to 1/20 and ((A) + ( 9))/(0)=1/α2~1/10 Multi-structure acrylic copolymer [■] 1~
A thermoplastic resin composition having excellent heat resistance and impact resistance and comprising 99-weight i[. Z methacrylic resin, polycarbonate, AS resin,
A heat-resistant material with excellent heat resistance and impact resistance according to claim 1, which is obtained by adding at least 98 weight percent or less of at least one resin selected from methyl methacrylate-styrene copolymer, polystyrene, polyester, and nylon. Plastic resin composition.