JPH02265945A - Vinyl chloride resin composition - Google Patents

Abstract

PURPOSE:To obtain a vinyl chloride resin composition excellent in both heat resistance and impact resistance as well as good in processability by blending a vinyl chloride resin with a rubber-modified thermoplastic resin prepared by graft-polymerizing a specified monomer mixture in the presence of a rubber component in two stages. CONSTITUTION:100 pts.wt. vinyl chloride resin (A) (densirably of a degree of polymerization of about 600-2500) is blended with 5-100 pts.wt. desirably 7-90 pts.wt. rubber- modified thermoplastic resin (B) to obtain a vinyl chloride resin composition useful for automobile components, household electrical appliances, building materials, etc. The rubber-modified thermoplastic resin (B) can be obtained by graft-polymerizing 100 pts.wt. monomer mixture comprising 0.5-10wt.% unsaturated dicarboxylic acid anhydride, 5-35wt.% maleimide compound, 0-25wt.% alkyl (meth)acrylate, 3-30wt.% vinyl cyanide monomer and 45-91.5wt.% aromatic vinyl monomer in such a way that in the presence of a rubber component of 4 to 40 parts, the unsaturated dicarboxylic acid anhydride is copolymerized with the other monomers except the maleimide compound in stage 1 before the phase inversion, and the maleimide compound is copolymerized with other monomers except the unsaturated dicarboxylic acid anhydride in stage 2 after the phase inversion.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is applicable to building materials such as pipes, roofing materials, window frames, electrical parts,
The present invention relates to a vinyl chloride resin composition that has excellent heat resistance, impact resistance, and processability and is useful for various molded products such as automobile parts and miscellaneous goods.

[Conventional technology]

Vinyl chloride resin is widely used in various fields because it is inexpensive and has excellent physical and chemical properties, but it has the disadvantage of poor heat resistance and impact resistance, which limits its range of use. There is.

For this reason, many attempts have been made to improve the heat resistance and impact resistance of vinyl chloride resins. For example, a method of blending a rubber-modified thermoplastic resin obtained by graft polymerizing monomers such as methacrylate, methacrylic acid, maleic anhydride, maleimide compound, acrylonitrile, acrylic ester, and methacrylic ester is disclosed in JP-A-57 -162745, 60-
No. 248758, No. 61-143459, No. 61-1
In each publication such as No. 62543 and No. 62-57446,
Disclosed.

[Problem to be solved by the invention]

However, most of the above-mentioned known blending methods use a combination of two types of rubber-modified thermoplastic resins with different types of monomers, or use a rubber-modified thermoplastic resin together with a resin component that does not contain a rubber component. However, due to the content of the rubber component or the type of monomer used, the heat resistance is still insufficient or the impact resistance is insufficient, making it difficult to use vinyl chloride resins. In trying to expand the number of products, it could not be said that the heat resistance, impact resistance, and processability were all sufficiently satisfactory.

In view of the above-mentioned current situation, the present invention aims to provide a vinyl chloride resin composition that has excellent processability inherent to vinyl chloride resins, as well as excellent heat resistance and impact resistance. The purpose is

[Means to solve the problem]

As a result of intensive studies to achieve the above object, the present inventors have found that by blending a specific rubber-modified thermoplastic resin with a vinyl chloride resin, the properties of heat resistance, impact resistance, and processability can be improved. The inventors have discovered that an excellent vinyl chloride resin composition can be obtained, and have completed the present invention.

That is, the present invention includes: A) 100 parts by weight of vinyl chloride resin, B) 4 parts by weight of the rubber component.
in the presence of ~40 parts by weight of unsaturated dicarboxylic anhydride.
5-10% by weight of a maleimide compound, 5-35% by weight of a maleimide compound, 0-25% by weight of an acrylic acid alkyl ester and/or a methacrylic acid alkyl ester, 3-30% by weight of a vinyl cyanide monomer, and an aromatic vinyl monomer. 45～91,
In the first step before phase inversion, 100 parts by weight of a monomer mixture consisting of 5% by weight is polymerized with an unsaturated dicarboxylic anhydride and other monomers excluding the maleimide compound, using a solution or bulk polymerization method. A rubber-modified thermoplastic resin obtained by carrying out two-step graft polymerization in which the maleimide compound and other monomers excluding the unsaturated dicarboxylic acid anhydride are polymerized in the second step after phase inversion. Parts by weight of the vinyl chloride resin composition are blended.

[Structure and operation of the invention]

The vinyl chloride resin that is component A used in the present invention is a homopolymer of vinyl chloride, a copolymer of vinyl chloride and ethylene, propylene, vinyl acetate, etc., or a polymer of vinyl chloride and vinyl ethers, acrylic acid, methacrylate, etc. Acid esters, methacrylamide, acrylonitrile,
It contains a copolymer with a maleimide compound etc.
Any production method such as bulk polymerization, suspension polymerization, emulsion polymerization, or solution polymerization may be used. Moreover, mixtures of these and mixtures of these with post-chlorinated vinyl chloride resins can also be used. The degree of polymerization is not particularly limited, but is generally 600 to 2.
．． Those having a degree of polymerization of 500 degrees are preferred.

The rubber-modified thermoplastic resin that is component B used in the present invention is a monomer consisting of an unsaturated dicarboxylic anhydride, a maleimide compound, a vinyl cyanide monomer, and an aromatic vinyl monomer in the presence of a rubber component. a monomer mixture, or a monomer mixture obtained by further adding an acrylic acid alkyl ester and/or a methacrylic acid alkyl ester [hereinafter collectively referred to as (meth)acrylic acid alkyl ester],
Using a solution or bulk polymerization method, a two-step graft polymerization is performed in which the unsaturated dicarboxylic acid anhydride is copolymerized in the first step before phase inversion, and the maleimide compound is copolymerized with other monomers in the second step after phase inversion. This can be obtained by

Examples of the rubber component used here include polybutadiene, styrene-butadiene block polymer, nitrile rubber, maleated rubber, polyisoprene rubber, butadiene-acrylonitrile rubber, and ethylene-propylene-diene terpolymer. The amount of this rubber component used is 4 parts by weight per 100 parts by weight of the monomer mixture.
It is preferable to set the amount to be 40 parts by weight, particularly preferably 5 to 35 parts by weight. If it is less than 4 parts by weight, impact resistance will be insufficient, and if it exceeds 40 parts by weight, heat resistance and processability will be reduced.

Among the monomer mixtures to be graft-polymerized to this rubber component, unsaturated dicarboxylic anhydrides include maleic anhydride, chloromaleic anhydride, dichloromaleic anhydride, citraconic anhydride, itaconic anhydride, and phenyl Maleic anhydride, aconitic anhydride, etc.
One or a mixture of two or more of these may be used.

In addition, as maleimide compounds, N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide,
N-isopropylmaleimide, N-butylmaleimide, N
-tert-butylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, N-hydroxyphenylmaleimide, N-lauroylmaleimide, etc., and one or a mixture of two or more of these may be used.

Examples of vinyl cyanide monomers include acrylonitrile, meccrylonitrile, and α-chloroacrylonitrile, with acrylonitrile being particularly preferred. Examples of the aromatic vinyl monomer include styrene, α-methylstyrene, 0-chlorostyrene, p-chlorostyrene, and vinyltoluene, and one or a mixture of two or more of these may be used.

Furthermore, as the (meth)acrylic acid alkyl ester, those whose alkyl group usually has 1 to 22 carbon atoms are preferable, and specifically, methyl (meth)acrylate, ethyl (meth)acrylate, (meth)acrylate, etc. Butyl acrylate, tert-butyl (meth)acrylate, tert-butylcyclohexyl (meth)acrylate, amyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (meth)acrylate ) decyl acrylate,
Lauryl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, (meth)acrylate
Examples include benzyl acrylate, and one of these
Species or mixtures of two or more species may be used.

The composition of these monomer mixtures is preferably 0.5 to IO% by weight, particularly preferably 0.8% by weight for unsaturated dicarboxylic anhydrides.
If it is less than 0.5% by weight, heat resistance will not improve, and if it exceeds 10% by weight, impact resistance or processability will decrease. For maleimide compounds, the content is 5 to 35% by weight, particularly preferably 8 to 30% by weight; if it is less than 5% by weight, heat resistance will not improve, and if it exceeds 35% by weight, impact resistance and processability will decrease. For vinyl cyanide monomers, the content is 3 to 30% by weight, particularly preferably 5 to 25% by weight; if it is less than 3% by weight, impact resistance will not improve, and if it exceeds 30% by weight, heat resistance will decrease. do. 45-91 for aromatic vinyl monomers
．． 5% by weight, particularly preferably 60-85% by weight, and 4% by weight.
If it is less than 5% by weight, it will become brittle, and if it exceeds 91.5% by weight, no improvement in heat resistance or impact resistance will be observed. moreover,(
0 to 25% by weight for meth)acrylic acid alkyl esters
The monomer is particularly preferably used in an amount of 0 to 20% by weight, and is used as necessary to improve properties such as heat resistance and processability, but if it exceeds 25% by weight, the Impact resistance does not improve.

The two-step graft polymerization using such a rubber component and a monomer mixture is carried out, for example, as follows. First, a predetermined amount of a solution prepared by dissolving a rubber component in a solvent or an aromatic vinyl monomer and adding a vinyl cyanide monomer or an alkyl (meth)acrylic acid ester to the polymerization system is first added.
Stir to mix well. Next, while purging the polymerization system with nitrogen gas, a first aromatic vinyl monomer solution in which a predetermined amount of unsaturated dicarboxylic acid anhydride is dissolved is added under stirring, usually at 90 to 120°C, and polymerization is carried out. and continue polymerization until phase inversion occurs. From the point of phase inversion, as a second step, a second aromatic vinyl monomer solution in which a predetermined amount of maleimide compound is dissolved is added to continue the polymerization, and the polymerization is allowed to proceed until the target conversion rate is reached. That's fine.

In addition, in the above-mentioned graft polymerization method, regarding the phase inversion of the polymerization system, the viscosity of the polymerization system changes rapidly at the time of phase inversion.
In other words, it can be easily determined by a significant decrease in viscosity or an increase in turbidity (becomes markedly cloudy).

In addition, in the above graft polymerization method, various known polymerization initiators such as benzoyl peroxide, lauroyl peroxide, dicumyl peroxide, and azobisisobutyronitrile are used as necessary to promote the polymerization reaction. In addition, various additives such as polymerization regulators may be added to the polymerization system.
Any solution polymerization method may be used. In the solution polymerization method, appropriate solvents such as benzene, toluene, xylene, chlorobenzene, bromobenzene, methyl ethyl ketone, and methyl isobutyl ketone are used, but there is no particular difference from the bulk polymerization method other than the use of these solvents.

By such a graft polymerization method, the polymerization solution that has reached the target conversion rate is then dried under reduced pressure using a thin film distillation machine, a Flasher-1 extruder, etc., to form pellets or the like, which is component B of the present invention. It is considered to be a rubber-modified thermoplastic resin in granular form. The molecular weight of the resin component excluding the rubber component in this resin is not particularly limited, but it is generally used by gel permeation chromatography (hereinafter referred to as GPC).
weight average molecular weight of about 50,000 to 300,00
Preferably, it is in the range of 0.

The vinyl chloride resin composition of the present invention is prepared by blending the rubber-modified thermoplastic resin, which is the above-described component B, with the vinyl chloride resin, which is the component A, and mixing the mixture uniformly. Here, the blending ratio of both of the above components is 10% of component A.
The amount of component B is preferably 5 to 100 parts by weight, particularly preferably 7 to 90 parts by weight, based on 0 parts by weight. If component B is less than 5 parts by weight, heat resistance and impact resistance will decrease, and
If the amount exceeds 1 part by weight, processability deteriorates, which is not preferable.

The method for uniformly mixing components A and B is not particularly limited, and may be carried out by mixing both components in advance using a Henschel mixer, ribbon blender, etc., and then melt-mixing this using a Banbury, extruder, roll, etc. Alternatively, both components may be melt-kneaded while being quantitatively supplied to a continuous kneader.

The vinyl chloride resin composition of the present invention contains small amounts of heat stabilizers, plasticizers, antioxidants, ultraviolet absorbers, fillers, lubricants,
Foaming agents, flame retardants, processing aids, pigments, etc. can be added as appropriate.

In addition, when used in applications where high impact resistance is desired, conventionally known impact modifiers, such as
MBS resin in which aromatic vinyl monomer and methyl methacrylate are graft-polymerized on polybutadiene, ABS resin in which aromatic vinyl monomer and acrylonitrile are graft-polymerized on polybutadiene, aromatic vinyl monomer, methyl methacrylate and acrylonitrile on polybutadiene. MABS resin etc. which are graft polymerized may be blended.

〔Effect of the invention〕

The vinyl chloride resin composition of the present invention has good processability and exhibits excellent physical properties such as heat resistance and impact resistance, so it is widely used in various fields such as automobile parts, home appliances, and building materials. can do.

〔Example〕

Next, the present invention will be specifically explained using reference examples, examples, and comparative examples. Hereinafter, parts and % mean parts by weight and % by weight, respectively.

Reference example 1 Polybutadiene rubber (trade name: Diene 3 manufactured by Asahi Kasei Kogyo Co., Ltd.)
5AS) and 600 parts of styrene were placed in a polymerization pot and stirred to dissolve the rubber. After dissolving, 50 parts of acrylonitrile was added and stirred to mix well.

Next, gas was replaced by blowing nitrogen into the polymerization reactor, and when the temperature rose to 100°C, 35.1 parts of maleic anhydride and 0.09 parts of penzoyl baroxide were dissolved in 224 parts of styrene in advance. The prepared first-stage dropping solution was added dropwise at a constant rate over a period of 152 minutes. At this time, the viscosity of the system suddenly decreased and the system became cloudy, indicating a phase inversion.

At this time, a small amount of sample was taken out from the polymerization reactor and unreacted maleic anhydride was detected using gas chromatography. Further, the solid content at this point was measured and found to be 20.8%.

Subsequently, at the same temperature, 46.2 parts of N-cyclohexylmaleimide and 0 parts of benzoyl peroxide were added in advance.
．． The second stage dropping solution, in which 14 parts of styrene had been dissolved in 242 parts of styrene, was quantitatively added dropwise over a period of 216 minutes to continue polymerization.

After the dropwise addition was completed, the mixture was rapidly cooled to 50°C, a small amount of the sample was taken out, and the amount of unreacted N-cyclohexylmaleimi F and acrylonitrile was measured by gas chromatography. Although N-cyclohexylmaleimide was not detected, it was confirmed that acrylonitrile was contained at 0.79% (based on the polymerization solution). Moreover, when the solid content concentration of the polymerization solution was measured, it was found to be 43.1%.

Finally, the polymerization solution was dried under reduced pressure to obtain a rubber-modified thermoplastic resin. This resin was separated into a rubber component and a resin component according to "Polymer Analysis Hand Bluff", Japan Society for Analytical Chemistry, Asakura Shoten, p. 278 (1985), and after 10 minutes, the resin component was dissolved in tetrahydrofuran. The weight average molecular weight was measured by C.

The results are shown in Table 2 below, along with the resin composition of the rubber-modified thermoplastic resin.

Reference Example 2 Polybutadiene rubber (diene 3
5AS) and 600 parts of styrene were placed in a polymerization pot and stirred to dissolve the rubber.1. Add 50 parts of acrylonitrile, mix well, and after purging with nitrogen, raise the temperature to 1.00°C. When this temperature is reached, the first stage and second stage in Reference Example 1.
A solution containing the combined drops of the liquids added in step 1, i.e., 35.1 parts of maleic anhydride, 46.2 parts of N-cyclohexylmaleimide, and 0.23 parts of benzoyl peroxide dissolved in 466 parts of styrene, was heated for 370 minutes. was quantitatively added dropwise to polymerize.

After the dropwise addition was completed, the polymerization was stopped by rapidly cooling to 50'C in the same manner as in Reference Example 1. At that time, a small amount of sample was taken and the amount of unreacted acrylonitrile, maleic anhydride, and N-cyclohexylmaleimide was measured by gas chromatography. Maleic anhydride and N-cyclohexylmaleimide were not detected. Although there was no acrylonitrile, I was convinced that it contained 0.80% acrylonitrile. Moreover, the solid content of the polymerization liquid was 42.9%.

Finally, the polymerization solution was dried under reduced pressure to obtain a rubber-modified thermoplastic resin. The resin composition and the weight average molecular weight of the resin component measured in the same manner as above are shown in Table 2 below.

Reference Examples 3 to 11.14 and 15 As shown in Table 1, the amount charged in the polymerization kettle, the polymerization temperature, the composition of each dropping liquid in the first stage and the second stage, and the dropping time were changed,
Further, polymerization was carried out in the same manner as in Reference Example 1, except that N-phenylmaleimide was used in place of N-cyclohexylmaleimide. After polymerization, it was rapidly cooled to 50"C and dried under reduced pressure to obtain 11 types of rubber-modified thermoplastic resins. When N-phenylmaleimide in step) was investigated in the same manner as in Reference Example 1, none was detected.

The solid content at each point in time and the amount of unreacted acrylonitrile after polymerization were measured, together with the resin composition of the obtained rubber-modified thermoplastic resin and the weight average molecular weight of the resin component measured in the same manner as above. It is shown in Table 2.

Reference Example 12 In the same manner as Reference Example 1, polybutadiene rubber (
75 parts of diene 35AS> and 600 parts of styrene were charged and stirred to dissolve the rubber well, and then 50 parts of acrylonitrile was added and mixed well.

Next, after nitrogen substitution, the temperature was raised to 95°C, and at the same time as this temperature was reached, 31.5 parts of maleic anhydride, 1.49.7 parts of methyl methacrylate, and 0.11 parts of hensyl peroxide were added in advance. A first dropping solution containing 233 parts of styrene dissolved in 233 parts of styrene was quantitatively added dropwise over a period of 147 minutes to polymerize.

At this time, a phase inversion was observed in the polymerization system, so a small amount of sample was taken out from the polymerization vessel and unreacted maleic anhydride and methyl methacrylate were examined by gas chromatography, but no unreacted maleic anhydride and methyl methacrylate were detected. Further, the solid content at this point was examined and found to be 22.1%.

Subsequently, at the same temperature, 52.1 parts of N-phenylmaleimide, 43.7 parts of methyl methacrylate, and 0.17 parts of hensyl peroxide were added in advance to 241 parts of styrene.
Polymerization was continued by quantitatively dropping the second dropping solution, which had been dissolved in the same volume, over a period of 203 minutes.

After the dropwise addition was completed, the temperature was rapidly cooled to 50° C., and the amount of unreacted monomer was measured. N-phenylmaleimide and methyl methacrylate were not detected, but acrylonitrile was 0.7
It contained 3%. In addition, the solid content of the polymerization solution was 43.7%.
Met.

Finally, the polymerization solution was dried under reduced pressure to obtain a rubber-modified thermoplastic resin. The resin composition and the weight average molecular weight of the resin component measured in the same manner as above are shown in Table 2 below.

Reference Example 13 In the same manner as Reference Example 1, polybutadiene rubber (
75 parts of diene 35AS) and 700 parts of α-methylstyrene were charged, stirred to dissolve the rubber, and then 45 parts of acrylonitrile were added and mixed well.

Next, after nitrogen substitution, the temperature was raised to 105°C, and at the same time as reaching this temperature, anhydrous maleic M 35.
6 parts of benzoyl peroxide and 0.16 parts of benzoyl peroxide were dissolved in 234 parts of styrene.
It was gradually added dropwise quantitatively and polymerized.

At this time, phase inversion was observed in the polymerization system, so a small amount of sample was taken out and unreacted monomers were examined, and no maleic anhydride was detected. Further, the solid content at this point was examined and found to be 19.2%.

Subsequently, at the same temperature, 53.6 parts of N-phenylmaleimide and 0.20 parts of benzoyl peroxide were added in advance.
A second dropping solution, in which 1.5 parts of styrene had been dissolved in 244 parts of styrene, was quantitatively added dropwise over a period of 216 minutes to continue polymerization.

After the dropwise addition was completed, the temperature was rapidly cooled to 50 DEG C., and unreacted monomers were examined. No N-phenylmaleimide was detected, but acrylonitrile was found to be 0.66%.

The solid content of the polymerization solution was 41.9%.

Finally, the polymerization solution was dried under residual pressure to obtain a rubber-modified thermoplastic resin. The resin composition and the weight average molecular weight of the resin component measured in the same manner as above are shown in Table 2 below.

In addition, in Tables 1 and 2, AN is acrylonitrile, MAN
is maleic anhydride, MMA is methyl methacrylate, B
P-0 is benzoyl peroxide.

Example 1 Vinyl chloride resin [trade name Sumilit 5 manufactured by Juju Kagaku ■
X-1,1F; degree of polymerization 1,050), the rubber-modified thermoplastic resin obtained in Reference Example 1, and various additives shown below were thoroughly mixed in a Henschel mixer.

Vinyl chloride resin 85 parts Rubber modified thermoplastic resin 15 parts Lead stearate
0.8 parts barium stearate 0
．． 6 parts 3 basic lead sulfate 1.8 parts Next, this mixture was kneaded for 5 minutes with a hot roll heated to a surface temperature of 85°C to form a sheet, and this was pressed at 190°C using a flat plate press at 100kg/ Press molding was performed for 10 minutes under CD conditions to produce test pieces made of vinyl chloride resin compositions to be used in each of the tests described below.

Examples 2-7 Reference Examples 1, 4.7. - The same procedure as in Example 1 was used, except that the rubber-modified thermoplastic resin obtained in 10.12.13 was used, and the number of parts of this and the vinyl chloride resin used was as shown in Table 3. , six types of test pieces were prepared.

Comparative Examples 1-10 Reference Examples 1-3. 5. 6. 8. 9. 11. 1
Example 1 was carried out in the same manner as in Example 1, except that the rubber-modified thermoplastic resin obtained in Example 415 was used, and the number of parts of this and the vinyl chloride resin used was as shown in Table 3.
0 kinds of test pieces were prepared.

Comparative Example 11 A test piece was prepared in the same manner as in Example 1, except that no rubber-modified thermoplastic resin was used at all and 85 parts of vinyl chloride resin was used.

Using each of the test pieces prepared in Examples 1 to 7 and Comparative Examples 1 to 11 above, the Vicat softening temperature, which is an index of heat resistance, the Izot impact strength, which is an index of impact resistance, and The melt flow rate, which is an index of processability, was measured.

Vicat softening temperature: JIS K7206, method A Izot impact strength: JIS K7110, notched The results of these measurements are shown in Table 3 below. In addition,
Each of the measured values means that the higher the value, the better the heat resistance, impact resistance, and workability.

As is clear from the results in Table 3, the vinyl chloride resin composition according to the present invention exhibits good J1 properties and is also excellent in both heat resistance and impact resistance η1 properties. It can be seen that

Claims (1)

[Claims] (1) In the presence of A) 100 parts by weight of vinyl chloride resin, B) 4 to 40 parts by weight of the rubber component, 0.5 to 10% by weight of unsaturated dicarboxylic anhydride, 5 to 35% by weight of maleimide compound, and acrylic 0 to 25% by weight of acid alkyl ester and/or methacrylic acid alkyl ester, 3 to 30% by weight of vinyl cyanide monomer, and 45 to 9% by weight of vinyl aromatic monomer.
100 parts by weight of a monomer mixture consisting of 1.5% by weight,
In the solution or bulk polymerization method, the first step before phase inversion is to polymerize the unsaturated dicarboxylic anhydride and other monomers excluding the maleimide compound, and the second step after phase inversion is to polymerize the maleimide compound and the unsaturated dicarboxylic acid anhydride. A vinyl chloride resin characterized by blending 5 to 100 parts by weight of a rubber-modified thermoplastic resin obtained by performing two-step graft polymerization with other monomers except saturated dicarboxylic acid anhydride. Composition.