JPS5839179B2 - thermoplastic resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermoplastic resin composition that has excellent weather resistance, transparency, heat resistance, and impact resistance.

Vinyl chloride resin has a major drawback of lacking impact resistance and heat resistance (thermal softening temperature).

Many proposals have been made to improve impact resistance, and improvements have been made by blending so-called impact resistance modifiers such as ABS resin and MBS resin.

However, even though these composite materials have improved impact strength, the rubber component reduces weather resistance and loses transparency. Therefore, resins using cross-linked acrylic ester as an elastic body have been proposed, and there are still efforts to improve impact resistance. In order to increase the temperature, a two-layer rubber structure has been proposed in which the core is made of a polymer with a high glass transition temperature and the outer shell is made of acrylic ester.

Furthermore, vinyl chloride resins that are blended with copolymers obtained by graft polymerizing appropriate monomers with these elastic polymers satisfy impact resistance and weather resistance, but their transparency is impaired, so in order to compensate for this, Proposals have also been made.

(Patent Application No. 49-148851) On the other hand, the heat resistance of polyvinyl chloride has its own limits, and its heat softening temperature is around 79°C, for example, at the Vicat softening temperature according to the ASTM l)-1525 method (load IK)). In addition, the softening temperature is further lowered by stabilizers and plasticizers that are usually added during molding.

Several methods have been proposed so far to improve the heat resistance of vinyl chloride resins.

That is, methods include copolymerizing a monomer that provides a polymer with a high softening point with vinyl chloride, or blending a polymer with a high softening point into a vinyl chloride resin.

However, even if these methods achieve the goal of increasing the softening point, they usually have major drawbacks such as not being able to improve impact resistance or impairing transparency.

As compositions that simultaneously improve heat resistance, transparency, and impact resistance, proposals have been made, for example, in Japanese Patent Application No. 5126953 and Japanese Patent Application No. 58389/1983, but in both cases, impact resistance Because it contains butadiene as a rubber component to develop the properties, there was a problem with weather resistance.

Therefore, in order to obtain a modifier that simultaneously imparts these weather resistance, heat resistance, and impact resistance without impairing transparency, the present inventors developed a composition that overcomes the drawbacks of the compositions of such known methods. As a result of intensive research into the subject matter, we succeeded in finding a composition that solved these drawbacks, and arrived at the present invention.

The present invention is a polyvinyl chloride polymer or a vinyl chloride copolymer (1) containing vinyl chloride in the 80 weight type, 10 to 9
0 parts by weight, 50 to 70 parts by weight of an acrylic acid alkyl ester having 2 to IO carbon atoms in the alkyl group, and 5 to 35 parts by weight of an aromatic vinyl compound, a total of 100 parts by weight,
and 0.1 to 5 parts by weight of a polyfunctional crosslinking agent having one or more allyl groups in the molecule, first emulsion polymerize a mixture of an aromatic vinyl compound and a polyfunctional crosslinking agent, and then emulsion polymerize the resulting polymer. A mixture of an acrylic acid alkyl ester and a polyfunctional crosslinker is polymerized in the presence of a coalesced latex to form an acrylic elastomer (4), which contains 40-8
A graft copolymer obtained by independently polymerizing a total of 60 to 20 parts by weight of monomers in a ratio of 0 parts by weight to 30 to 80 parts by weight of methyl methacrylate and 70 to 20 parts by weight of an aromatic vinyl compound ( B) 25-80 parts by weight, 35-65 parts by weight of α-methylstyrene, 10 parts by weight of methyl methacrylate
60 weight type, acrylonitrile 5 to 35 weight φ, and 75 to 20 parts by weight of a monomer mixture consisting of 5 to 35 weight φ of acrylonitrile and O to 10 superimposed vinyl monomers copolymerizable with these (total 100%). The resulting resin (by blending with 0 or
Alternatively, it consists of 10 to 90 parts by weight of resin (II) obtained by polymerizing 75 to 20 parts by weight of the monomer mixture constituting resin (C) in the presence of 25 to 80 parts by weight of graft copolymer (B). The gist of the invention is a thermoplastic resin composition that has good heat resistance, weather resistance, transparency, and impact resistance.

The contents of the present invention will be explained in detail below.

The graft copolymer CB) used in the thermoplastic resin composition of the present invention is obtained by emulsion polymerizing a mixture of an aromatic vinyl compound and a polyfunctional crosslinking agent having one or more allyl groups in the molecule. An acrylic elastomer (4
) is manufactured.

As the aromatic vinyl compound used here, in addition to styrene, vinyltoluene, α-methylstyrene, chlorostyrene, bromostyrene, etc. are used.

Acrylic acid alkyl esters include those having 2 to 10 carbon atoms in the alkyl group, such as ethyl acrylate, propyl acrylate, butyl acrylate, isobutyl acrylate, pentyl acrylate, hexyl acrylate, n acrylate. -octyl, 2-ethylhexyl acrylate, etc. are used.

These monomers may be used alone or in combination.

It is necessary for the polyfunctional crosslinking agent to have one or more allyl groups in its molecule in order to improve transparency, surface gloss and impact resistance.

Examples of the polyfunctional crosslinking agent having one or more allyl groups in the molecule include triallyl cyanurate, triallyl incyanurate, allyl methacrylate, allyl acrylate,
Diallyl itaconate, diallyl phthalate, etc. are used,
Particularly preferred are allyl methacrylate and triallyl cyanurate.

Divinylbenzene, acrylic acid or methacrylic acid, and diacrylic ester or Nisdel dimethacrylate, which are esters of polyhydric alcohols, which do not have an allyl group, have a small effect on improving transparency and surface gloss, so cross-linking with other allyl groups It can be used in combination with other agents, but cannot be used alone.

The reason for this is not clear, but crosslinking agents such as dimethacrylic acid esters work effectively for crosslinking the styrene phase.
Furthermore, since the two-layer structure rubber obtained by adding and polymerizing an acrylic acid ester has a high degree of swelling, it is considered that sufficient crosslinking as a two-layer structure rubber has not occurred.

Also, when graft polymerizing methyl methacrylate and an aromatic vinyl compound to a two-layer structure rubber, the type of crosslinking agent greatly influences the two-layer structure rubber using a polyfunctional crosslinking agent that does not have allyl groups. The effect of improving impact resistance, transparency, and surface gloss is poor, probably because no grafting reaction occurs.

The amount of the polyfunctional crosslinking agent used is 0.1 to 0.1 to the total of the acrylic acid alkyl ester and the aromatic vinyl compound.
5 parts by weight.

If the amount is less than this, the crosslinking efficiency will be poor, and if it is too much, the elastic body will lose its elasticity and become brittle, making it impossible to impart impact resistance to the thermoplastic resin composition.

Usual anionic, nonionic, and cationic surfactants can be used as emulsifiers for producing the acrylic elastomer (4), but anionic surfactants are preferred in terms of stability of the resulting polymer latex. preferable.

As a polymerization initiator, ordinary water-soluble inorganic initiators such as persulfates and perborates can be used alone, or in combination with sulfites, bisulfites, thiosulfates, etc., and used as redox initiators. You can also do it.

Furthermore, redox initiator systems such as organic hydroperoxide-ferrous salts, organic hydroperoxide-sodium formaldehyde sulfoxylates, or azo compounds can also be used.

Although the polymerization can be carried out at a temperature higher than the decomposition temperature of the initiator, a polymerization temperature of 60 to 80°C is preferred from the viewpoint of polymerization time.

The polymerization of the two-layer rubber may be carried out by adding the entire amount of the mixture of the polyfunctional crosslinking agent and each monomer at once, or while continuously adding the entire amount or a portion thereof.

From the viewpoint of stability of the polymerization system, heat of polymerization reaction, etc., it is preferable to carry out the polymerization while continuously adding the entire amount.

The particle size of the elastic latex has a great influence on the properties of the thermoplastic resin composition.

This is because it determines the size of the dispersed particles of the modifier dispersed in the vinyl chloride polymer; if it is too small, it is unfavorable for impact strength, and if it is too large, transparency will be impaired.

The particle size of the elastic latex is preferably in the range of 0.07 to 0.25 μm.

From the viewpoint of transparency, it is desirable for the acrylic elastic body (4) to have a refractive index as close as possible to that of the vinyl chloride polymer depending on its composition, but this elastic body must have elasticity to the extent that it can exhibit impact resistance. It is also necessary that the composition has the following properties.

In addition, transparency is also affected by the graft copolymer (B) obtained using this elastic body, and the graft copolymer (B) obtained using this elastic body
B) By balancing the overall composition ratio, it is possible to make the thermoplastic resin composition transparent and at the same time improve other properties.

In the composition of the acrylic elastic body (4), the greater the amount of alkyl acrylate, the more advantageous the impact strength of the resulting thermoplastic resin composition, but the worse its transparency.

On the other hand, when the aromatic vinyl compound is used in a predominant amount, the transparency of the thermoplastic resin composition becomes good, but the impact strength becomes weak.

In order to obtain a thermoplastic resin composition with a good balance between transparency and impact resistance, the composition of the acrylic elastic body (4) is as follows:
It is necessary to set the acrylic acid alkyl ester in a range of 50 to 70 weight φ and the aromatic vinyl compound in a range of 50 to 70 weight.

Even in this range, an elastic body obtained by simply random copolymerizing an acrylic acid alkyl ester and an aromatic vinyl compound, or an elastomer obtained by first polymerizing an acrylic acid alkyl ester as a core, and then polymerizing an aromatic vinyl compound as an outer shell. If the elastic body obtained by this method is used, the impact resistance of the resin composition will not be improved.

The graft copolymer (B) is obtained by graft polymerizing 60 to 20 parts by weight of monomer components in the presence of 40 to 80 parts by weight (as solid content) of an acrylic elastic latex.

A graft copolymer containing less than 40 parts by weight of the elastomer has a small effect on improving the impact strength of the thermoplastic resin composition, and when the amount of the elastomer is more than 80 parts by weight, the coagulation and drying process of the graft copolymer is difficult. In addition, the processability of the thermoplastic resin composition is extremely poor, and the impact strength is also low.

Examples of aromatic vinyl compounds used for this purpose include styrene, α-substituted styrene, nuclear-substituted styrene, and derivatives thereof, such as vinyltoluene, α-methylstyrene,
Chlorstyrene or the like is used.

If the proportion of methyl methacrylate in the graft monomer increases, the impact resistance and transparency will decrease, and the surface condition of the sheet will also deteriorate.

Furthermore, when the proportion of the aromatic vinyl compound increases, the compatibility with the vinyl chloride polymer deteriorates, and the impact resistance and transparency also decrease.

In graft polymerization, the polymerization is allowed to proceed by adding the entire amount of each monomer at once, continuously or discontinuously.

If a mixture of methyl methacrylate and an aromatic vinyl compound is simultaneously added and graft polymerized, the transparency of the thermoplastic resin composition, the surface properties of the sheet, and the weather resistance deteriorate.

The graft polymerization is carried out subsequent to the production of the elastomer (4) latex, or again in a separate reactor under normal emulsion polymerization conditions with or without the addition of an initiator, polymerization regulator, crosslinking agent, etc. be able to.

Further, these materials may be those used in manufacturing the elastic body (4) or may be other materials.

The obtained latex of the graft copolymer (B) may be used as it is in the next step, or it may be dried, for example, after salting out and coagulating and washing, preferably in the form of a powder and used in the next step. May be used.

JIIC) is produced primarily for the purpose of improving the heat resistance of thermoplastic resin compositions without impairing their transparency.

Resin IC) contains 35 to 65 parts by weight of α-methylstyrene, 10 to 60 parts by weight of methyl methacrylate, 5 to 35 parts by weight of acrylonitrile, and 0 parts of vinyl monomer copolymerizable with these.
~10% by weight (total 100%).

When α-methylstyrene is less than 355 parts by weight, the resulting final composition cannot be expected to have much heat resistance.

On the other hand, if α-methylstyrene exceeds 655 parts by weight, the polymerization rate becomes extremely slow and it takes a long time for the final polymerization conversion to reach 95% or more, which is not preferable.

If the amount of methyl methacrylate is less than 100 parts by weight, good transparency will not be provided, and if it exceeds 600 parts by weight, the heat resistance of the final assembly will decrease.

Acrylonitrile has an important role in accelerating the polymerization rate of the α-methylstyrene monomer mixture.

From the viewpoint of transparency, impact resistance, and heat resistance, α
- It seems that there is no problem in fixing the two components of methylstyrene and methyl methacrylate, but in reality, the polymerization rate is extremely slow in this binary system, so it is difficult to achieve high yields in a short period of time industrially. It is impossible to get things.

It also has the disadvantage that depolymerization tends to occur during molding.

If the amount of acrylonitrile is less than 5 parts by weight, it has no effect, and if it exceeds 35 parts by weight, coloring becomes large during molding of the final assembly, which is not preferable.

In addition to these monomers, other vinyl monomers can be used in O to 10 weight multipliers if desired.

The purpose of adding such monomers is to improve the processability of the final composition and to accelerate the copolymerization rate.

Such monomers include styrene, vinyltoluene, methacrylic acid, methyl acrylate, parachlorostyrene, maleic anhydride, methacrylonitrile, and the like.

Although it is not necessary to use these, it is not preferable to use more than 100 parts by weight from the viewpoint of heat resistance and transparency.

During polymerization, commonly known emulsifiers and catalysts are used.

Further, during polymerization, a known polymerization degree regulator such as tertiary dodecyl mercaptan may be added up to 5 parts by weight based on the monomer.

The monomer mixture may be added all at once, continuously, or in portions.

When the α-methylstyrene monomer mixture is polymerized in the presence of the graft copolymer latex (B), the polymer latex is coagulated as it is, washed, dehydrated, and dried to form a white powder (resin (If)). shall be.

Also, (B). (C) The two copolymers are mixed in an appropriate ratio to form the same resin (If).

As a mixing method, a method may be used, such as mixing in a latex state and then performing a coagulation treatment, or mixing in a powder state using a mixing roll, a panburi mixer, or the like.

The desired thermoplastic resin composition is obtained by polymerizing the resin ([l) thus obtained and the polyvinyl chloride resin (1).

When the proportion of graft copolymer (B) in resin (II) is less than 25 parts by weight, the impact resistance is better than that of polyvinyl chloride resin alone, but from a practical point of view, it is unsatisfactory. It is.

Further, the proportion of the graft copolymer (B) in the resin (II) is 8.
If it exceeds 0 parts by weight, molding processability will deteriorate and heat resistance will also decrease, which is not preferable.

When mixing the vinyl chloride polymer (1) and the resin (II), commonly known stabilizers, lubricants, molding aids, pigments, and fillers for vinyl chloride resins are used.

The final product is molded using known molding machines such as mixing rolls, calendar rolls, extruders, injection molding machines, and inflation molding machines.

Next, Examples will be shown to explain the composition of the present invention in more detail.

In the examples, parts and parts represent parts by weight, respectively.

Example I I) Production of acrylic elastic latex 45 copies “9”) (2:;7.tsu71J/L/□,.

Idialkyl sulfosuccinate sodium salt 0.4 parts Potassium persulfate 0.3 parts Water (total) 180.0 parts') (Tofu 11
；亙゛二″0.。

55 parts Potassium persulfate 0.3 parts Water 10.0 parts First, everything except the monomer and crosslinking agent was charged into a flask purged with nitrogen according to the above composition (1), and while keeping it at 70°C, styrene and allyl methacrylate were added. After dropping the mixed solution over 60 minutes, it was kept at the same temperature for 1 hour, and then the potassium persulfate aqueous solution from 2) was added to the latex, and n-butylene acrylate/L was added.
/.

After dropping the mixture of allyl methacrylate over 60 minutes,
The temperature was maintained at the same temperature for 1 hour to complete the polymerization.

The conversion rate was 96%, the average particle diameter of the obtained elastic latex was 0.155 μ, the feeding amount was 8.5%, and the degree of swelling was 6.
．． The gel content and swelling degree of the elastic latex in 1 are determined by drying the latex on a petri dish and
g) is immersed in methyl ethyl ketone at 30° C. for 48 hours, the weight of the swollen sample Wlg) and the weight of the bone-dried sample W2 g) are measured and calculated using the following formula.

b) Furthermore, as a comparative example, the same procedure as in a) was carried out, except that an elastic body was prepared by randomly copolymerizing styrene and n-butyl acrylate at the same time, polymerizing with n-butyl acrylate as the core, and then removing styrene. In addition to the elastic body polymerized as a shell, the elastic body polymerized only with n-butyl acrylate, polybutadiene is used as the elastic body,
Resin (II) was obtained in the same manner as in 1ii).

11) Production of graft copolymer Acrylic elastomer latex 70 parts (as solid content) Methyl methacrylate 15 parts Styrene
15 parts potassium persulfate
0.3 parts water (as a whole)
200 parts except for the seven dummers were placed in a nitrogen-substituted flask according to the above recipe, and methyl methacrylate was first added dropwise at 70°C over 30 minutes, kept at the same temperature for 1 hour, and then styrene was added dropwise over 30 minutes. , 10
The polymerization was completed by holding for 0 minutes.

The conversion rate was 96%, and the average particle diameter of the resulting graft copolymer latex was 0.170μ.

111) Preparation of terpolymer α-methylstyrene 50 parts Methyl methacrylate 40 parts Acrylonitrile 10 parts Potassium oleate
1.0 part Potassium rosinate
1.0 part potassium persulfate
0.4 parts tertiary dodecyl mercaptan
1.0 part water (as a whole) 200
Polymerization was carried out at 70° C. for 8 hours according to the above recipe.

The conversion rate was 98%.

The latex obtained in step 11) and the latex obtained in step 11D were mixed in a ratio of 2:3, coagulated with an aqueous solution of aluminum chloride in a ratio of 4 to the polymer and sulfuric acid in a ratio of 2 to the polymer, and washed. After drying, a white resin (II) powder is obtained.

Each of these resin compositions (II) was mixed with polyvinyl chloride having a degree of polymerization of 800, kneaded with a mixing roll for 6 minutes at 175°C to form a sheet, and then heated at 185°C-200°C.
The material was pressure-molded for 17 minutes using KP/Metal and its physical properties were investigated.

Furthermore, as a comparative example, chlorinated polyethylene (Ce-PE)
Table 1 shows the results of examining the physical properties of the vinyl chloride resin composition using the above-mentioned polyvinyl chloride resin.

Before roll mixing, 2.0 parts of dibutyltin male (2.0 parts of dibutyltin male), 0.5 parts of stearyl alcohol, 1.
It contains 0 parts of butyl stearate, i and o parts of a stabilizer lubricant of Metabrene® P-700 (processing aid manufactured by Mitsubishi Rayon Co., Ltd.).

As is clear from Table 1, the acrylic elastomer graft copolymers (R-3 to R-5) that do not contain a terpolymer have an improvement effect on impact strength, but the thermal softening temperature is lower than that of polyvinyl chloride. On the contrary, it is lower than when using resin alone.

On the other hand, a resin composition containing a terpolymer has a significantly improved softening temperature and also has a large effect of improving impact resistance.

The composition of the present invention in which the elastomer composition is styrene in the core and n-butyl acrylate in the outer shell may be different from other compositions, that is, n-butyl acrylate in the core and styrene in the outer shell, or styrene. Compared to a composition in which n-butyl acrylate is simply randomly copolymerized, the effect of improving impact resistance is much greater, the surface gloss is good, and the transparency is not reduced.

In addition, the elastic body composition of the present invention has a greater effect of the graft portion that improves compatibility with vinyl chloride resin and terpolymer than those with other compositions, and therefore has a softening temperature improvement effect. The high value also indicates the superiority of the present invention.

Furthermore, compositions using n-butyl acrylate as an elastic body have a large impact resistance improvement effect, but are opaque and have a low softening temperature.

Next, R-7, which corresponds to MBS, which is generally used as an impact modifier, has a high initial value of impact resistance, but
The retention rate of impact resistance after 0 hour exposure is extremely poor.

This also applies to chlorinated polyethylene, which is used for similar purposes.

This composition also has poor transparency and surface gloss.

Compared to these, the thermoplastic resin composition of the present invention is found to be significantly superior in terms of impact resistance retention after 1000 hours of exposure.

Example 2 An acrylic elastomer was produced in the same manner as in Example 1, except that ii) in a), styrene and n-butyl acrylate were changed as shown in Table 2, and the following procedure was carried out in the same manner as in Example 1. Table 2 shows the properties of each thermoplastic resin composition obtained by the operation.

As is clear from Table 2, as the amount of styrene is increased, transparency improves, but impact resistance decreases, and acrylic acid n
- As the amount of butyl is increased, the impact resistance improves, but the transparency decreases.

If the composition of the elastomer falls outside the range of the present invention, a resin composition having generally well-balanced properties cannot be obtained.

Example 3 The procedure was as in Example 1, except that in 1) styrene 4
In place of n-butyl acrylate, 60 parts of an acrylic acid alkyl ester as shown in Table 3 was used to produce an acrylic elastic body.

Table 3 below shows the properties of the thermoplastic resin composition obtained in the same manner as in Example 1.

Example 4 An acrylic elastic body was produced in the same manner as in Example 1, except that the type and amount of the cross-linking agent in 1) were changed as shown in Table 4.

Table 4 shows the swelling degree and gel content of each elastic body, as well as the properties of the thermoplastic tree composition obtained in the same manner as in Example 1 below.

The amount of these crosslinking agents is based on 100 parts of the total monomer (
Department).

As is clear from Table 4, when the amount of the crosslinking agent is small, the crosslinking efficiency is poor, and when it is too large, the elastic body loses its elasticity and becomes brittle, and in either case, the effect of imparting impact strength is small.

Further, even if a crosslinking agent having no allyl group is used, transparency tends to be impaired if a certain degree of impact strength is to be obtained, which is not preferable.

Example 5 1) Production of acrylic elastomer latex a) Styrene 47.5 parts Allyl methacrylate Potassium oleate Potassium anhydrous sodium carbonate Potassium persulfate water (as a whole) b) N-Butyl acrylate Allyl methacrylate First formulation a ) 0.8 parts shown in Table 5 0.45 parts 0.045 parts 0.15 parts 180 parts 52.5 parts 1.0 parts After completing the polymerization at 70°C, the obtained latex ( At a polymerization rate of 96% and an average particle size of 0.15μ, the monomer mixture was added dropwise at 70°C for 90 minutes according to recipe b) to proceed with polymerization, and after the dropwise addition was completed, the same temperature was maintained for an additional 1 hour to complete the polymerization. Ta.

Polymerization rate 98%, average particle size 0.16μ, gel content 89.
5%, and the degree of swelling was 6.5.

1i) Production of graft copolymer a) Acrylic elastomer latex obtained in 1) (as polymer solid content) 70 parts Sodium formaldehyde sulfoxylate 0.1 part b) C) d) Water (as a whole) ) Styrene cumene hydroperoxy methacrylate Methyl cumene hydroperoxy methacrylate Formaldehy 200 parts 15 parts 0.05 parts 15 parts ) 300 parts e) α-methylstyrene
150 parts methyl methacrylate
120 parts acrylonitrile 30 parts cumene hydroperoxide 1.5 parts First, put a) in a flask, keep it at 70°C, add b) dropwise for 30 minutes, hold for 1 hour, then add C) dropwise for 30 minutes. The temperature was maintained at the same temperature for 1 hour to complete the polymerization.

Subsequently, d) was added to this reaction solution to bring the temperature to 80°C, and then e) was added dropwise over 3 hours, followed by 30 minutes for 4 hours.
The polymerization was completed while maintaining the same temperature for several minutes.

The polymerization rate was 97.5%. This graft copolymer latex was treated in the same manner as in Example 1 to obtain a thermoplastic resin composition, and the physical properties are shown in Table 5.

As is clear from Table 5, if the particle size of the elastic latex is too small, the impact resistance will be weak, and if the particle size is too large, the transparency will decrease, so it is necessary to maintain a balance. A well-balanced particle size is obtained.

Example 6 The graft copolymer was prepared in the same manner as in Example 1, except that in 1) the elastomer latex (as solid content), styrene, and methyl methacrylate were variously changed so that the total amount was 100 parts. Manufactured.

Using these graft copolymers, the procedure was carried out in the same manner as in Example 11ii), except that the ratio of vinyl chloride resin to modifier was changed to 70/
Table 6 shows the properties of the thermoplastic resin composition obtained in the same manner as in Example 11ii) except that the temperature was 30.

As is clear from Table 6, when the amount of acrylic elastomer in the graft copolymer is small, the impact strength imparting effect is small, and when the elastomer content is large, the compatibility between the modifier and the vinyl chloride resin is reduced. As a result, transparency is impaired and surface gloss is also reduced.

Furthermore, the softening temperature also decreases, and the effect of imparting heat resistance is small.

Example 7 The procedure was as in Example 5, except that in 1) a), the amount of emulsifier was kept constant at 2.0 parts, and! Table 7 shows the properties of the thermoplastic resin composition (vinyl chloride resin 85%, resin (II) 15%) obtained by changing the monomers used in steps b) and c) as shown in Table 7. .

As is clear from Table 7, when the proportion of styrene in the graft monomer is increased, the transparency becomes extremely poor and the impact strength also decreases.

On the other hand, if the proportion of methyl methacrylate is too high, unmelted spots will be generated on the sheet surface and the sheet surface condition will be impaired.

Further, a sheet obtained by simply random copolymerization of styrene and methyl methacrylate is not preferable because it significantly impairs the transparency of the sheet and further deteriorates the surface gloss.

Example 8 The polymerization was carried out in the same manner as in Example 1, except that the monomer composition was changed as shown in Table 6 during the production of the terpolymer in 1 [1), and the resulting resin was Table 8 shows the physical properties of the thermoplastic resin composition containing 30φ of ([I) and the time required for the conversion rate to reach 95% during polymerization of the ternary monomer mixture.

As is clear from the table, the α-methylstyrene content is 35
% or less has poor heat resistance.

Furthermore, when the number of α-methylstyrene is 65 or more, the polymerization time becomes extremely long, which is extremely disadvantageous in production.

Furthermore, these systems have poor clarity in the final composition.

Even if α-methylstyrene is in the range of 35 to 65%, it does not contain methyl methacrylate at all, i.e., the monomer composition of the ternary copolymerization is a binary system of α-methylstyrene and acrylonitrile. The properties are unexpectedly poor, and the molded product is highly colored, so it lacks practical value.

In addition, when the monomer composition is a binary system of α-methylstyrene and methyl methacrylate, when α-methylstyrene is M1 and methyl methacrylate is M2, the copolymerization reactivity ratio is r
l: o, 14, r2=0.50, and the azeodorope composition is 40.7% α-methylstyrene,
In a copolymerization composition in which methyl methacrylate is 59.3% and α-methylstyrene is about 40% or more, the proportion of α-methylstyrene in the remaining monomer gradually increases as the polymerization progresses, and As a result, the polymerization rate is extremely reduced, making it impossible to obtain a terpolymer with a high polymerization rate.

If the proportions of α-methylstyrene, methyl methacrylate, and acrylonitrile are within the range of the present invention, there will be no problems in producing the terpolymer, and the physical properties of the final composition will be excellent. .

Example 9 The procedure was carried out in the same manner as in Example 1, except that the mixing ratio (as solid content) of the graft copolymer obtained in 1:) and the terpolymer obtained in 1ii) is shown in Table 9. The physical properties of the thermoplastic resin mixture having the composition shown in Table 9 obtained by the same procedure as in Example 1 are as follows. ) itself is shown in Table 9. As is clear from Table 9, compositions containing 25% or less of graft polymer have good heat resistance, but low impact resistance and are of no practical value.

Moreover, if the graft polymer exceeds 80, although the impact resistance is good, hardly any improvement in heat resistance can be expected, and all the objects of the present invention cannot be satisfied.

Example 10 Tree Fl'ff(U) obtained by the same operation as Example 1
were blended with vinyl chloride resin in the proportions shown in Table 10, and the physical properties of the resulting thermoplastic resin composition are shown in Table 10.

As is clear from the table, the vinyl chloride resin alone shown in the comparative example has good transparency but poor impact resistance and heat resistance.

In addition, resins with a (U) content exceeding 90 have relatively little impact strength improvement effect, are not economical, and have poor moldability and poor thermal stability, resulting in poor light transmission due to poor coloring power of the molded product. rate decreases.

The material according to the present invention has good impact resistance, heat resistance, and transparency, and is also excellent in moldability.

Claims (1)

[Scope of Claims] 1. 10 to 90 parts by weight of a polyvinyl chloride polymer or a vinyl chloride copolymer (I) containing 80% vinyl chloride, and 2 to 10 carbon atoms in the alkyl group. A total of 100 parts by weight of 50 to 70 parts by weight of an acrylic acid alkyl ester having a polyester and 50 to 30 parts by weight of an aromatic vinyl compound, and 0.1 to 0.1 parts by weight of a polyfunctional crosslinking agent having one or more allyl groups in the molecule. Using 5 parts by weight, a mixture of an aromatic vinyl compound and a polyfunctional crosslinking agent was first emulsion polymerized, and then a mixture of an acrylic acid alkyl ester and a polyfunctional crosslinking agent was polymerized in the presence of the obtained polymer latex. to produce an acrylic elastic body (4), and this elastic body (4) 40-8
A graft copolymer obtained by individually polymerizing a total of 60 to 20 parts by weight of monomers in a ratio of 30 to 80 parts by weight of methyl methacrylate and 70 to 20 parts by weight of an aromatic vinyl compound to 0 parts by weight. Combined CB) 25 to 80 parts by weight and α-
Methyl styrene 35-65 weight type, methyl nuccrylate 10-60 weight φ, acrylonitrile 5-35 weight type,
and 75 to 20 parts by weight of a resin (C) consisting of 0 to 10 weight φ (total 100%) of copolymerizable vinyl monomers with 10 to 90 parts by weight of a resin (II). A thermoplastic resin composition with good weather resistance, transparency, and impact resistance. 2 10 to 90 parts by weight of a polyvinyl chloride polymer or a vinyl chloride copolymer (1) containing 80% vinyl chloride and an acrylic acid alkyl ester having 2 to 10 carbon atoms in the alkyl group Using a total of 100 parts by weight of 50 to 70 parts by weight and 50 to 30 parts by weight of the aromatic vinyl compound, and 0.1 to 5 parts by weight of a polyfunctional crosslinking agent having one or more allyl groups in the molecule, First, a mixture of an aromatic vinyl compound and a polyfunctional crosslinking agent is emulsion polymerized, and then a mixture of an acrylic acid alkyl ester and a polyfunctional crosslinking agent is polymerized in the presence of the obtained polymer latex to form an acrylic elastomer. (4), and add 40 to 80 parts by weight of this elastic body to 60 to 20 parts by weight of monomers in a ratio of 30 to 80 parts by weight of methyl methacrylate and 75 to 20 parts by weight of an aromatic vinyl compound. In the presence of 25 to 80 parts by weight of a graft copolymer (B) obtained by individually polymerizing each part, α
- A monomer consisting of methyl styrene 35 to 65 weight type, methyl nuccrylate 10 to 60 weight φ, acrylonitrile 5 to 35 weight type, and vinyl monomer O to 10 superimposed type (total 100 φ) copolymerizable with these. mass mixture 75-2
A thermoplastic resin composition having good heat resistance, weather resistance, transparency, and impact resistance, comprising 10 to 90 parts by weight of resin (II) obtained by polymerizing 0 parts by weight.