JPS61162543A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To obtain a composition having excellent heat-resistance, weather- resistance, impact-resistance and moldability, by compounding a vinyl chloride polymer to a copolymer of a maleimide compound and a methacrylate monomer. CONSTITUTION:The objective composition is produced by compounding (A) a vinyl chloride polymer to (B) a copolymer derived from (a) 0.5-60(wt)% maleimide compound of formula (R is H, 1-15C alkyl, cycloalkyl or aryl), (b) 99.5-40% methacrylate monomer containing >=50% methyl methacrylate, and (c) 0-50% other monomer copolymerizable therewith (A+B+C=100%). The amounts of the components A and B are 95-50% and 5-50%, respectively.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention has excellent heat resistance, weather resistance, impact resistance, and moldability, and is applicable to building materials such as roofing materials and sizing, electrical equipment parts, automobile parts, pipes, etc. The present invention relates to a thermoplastic resin composition useful for manufacturing various molded products such as hoses and disks.

Specifically, the present invention relates to a thermoplastic resin composition comprising a copolymer obtained by essentially containing a maleimide compound and a methacrylic acid ester monomer, and a vinyl chloride polymer.

(Prior art) Vinyl chloride resin has excellent physical and chemical properties and is used in a wide range of areas. Since it has the disadvantage of poor properties, its use is currently restricted depending on the application, as the applications have become increasingly diverse.

To improve heat resistance, there is a so-called post-chlorinated vinyl chloride resin that is made by further chlorinating vinyl chloride resin with chlorine, but although it has improved heat resistance compared to conventional vinyl chloride resin, it has poor moldability. On the other hand, the range of applications is greatly limited.

In order to improve moldability, conventional methods include adding acrylic resin containing methyl methacrylate as a processing aid (Japanese Patent Publication No. 52-1746, Japanese Patent Publication No. 52-49).
No. 020) and methods that make extensive use of plasticizers have been adopted.

Although moldability is improved by adding these acrylic processing aids, heat resistance is reduced. In particular, in the case of post-chlorinated vinyl chloride resin, a large amount of processing aid is required, and in some cases it may be necessary to use a blend with conventional vinyl chloride resin, which may reduce the heat resistance that the resin originally possesses. It is not possible to achieve the full potential and is forced to have low heat resistance. To improve the weather resistance of vinyl chloride resins, a method of blending them with acrylic resins has been adopted, and to improve their impact resistance, a method of blending them with graft polymers containing soft rubber components has been adopted. There are, but
In either case, heat resistance decreases.

As described above, although each of the individual properties has been improved by conventional methods, a thermoplastic resin composition with good heat resistance, weather resistance, impact resistance, and moldability has not been obtained.

(Problems to be Solved by the Invention) In view of these points, the present inventors have conducted intensive research and found that heat resistance, weather resistance, impact resistance, and moldability are good by using a specific copolymer. The inventors have discovered that a thermoplastic resin composition can be obtained, leading to the present invention.

(Actions and means for solving the problems) The present invention provides a maleimide compound represented by cA) 0.5 to 60% by weight, methacrylic acid ester monomer containing at least 50% by weight of methyl methacrylate 03) 99.
5 to 40% by weight and other monomers copolymerizable with these (
C) O to 50% by weight (however, (1)) and (C)
The total of the components is 100% by weight. ) Provides a thermoplastic resin composition having excellent heat resistance, weather resistance, water resistance, impact resistance, and moldability, which is composed of the obtained copolymer (I) and a vinyl chloride polymer (■). It is something to do.

The copolymer (1) is composed of a maleimide compound (4) and a methacrylic acid ester monomer (), and other monomers (C) as necessary.

The maleimide compound (4) imparts heat resistance and solvent resistance to the resin composition, and is expected to have the effect of suppressing resin deterioration by capturing free chlorine in the resin composition and reducing electrical resistance. It also exhibits effects that were previously absent.

The methacrylic acid ester monomer (1) is a component for improving weather resistance, water resistance, impact resistance, and optical properties.

In plastic products, improved water resistance is particularly preferable because it greatly contributes to dimensional stability.

Therefore, copolymer (1) and vinyl chloride polymer (If)
Due to the synergistic effect of each component of the copolymer (1), the resin composition of the present invention consisting of The resulting thermoplastic resin composition maintains flame retardancy without loss, has improved heat resistance, weather resistance, water resistance, and impact resistance, has excellent dimensional stability, and has low free chlorine.

The maleimide compounds used in the copolymer (1) are those represented by the above general formula, such as maleimide, N-methylmaleimide F#, N-ethylmaleimide, N-propylmaleimide, N-isobutyl. Maleimide, N-butylmaleimide, N-isobutylmaleimide, N-tert-butylmaleimide, N-
Cyclohexylmaleimide, N-phenylmaleimide,
N-Chlorphenylmaleimide, N-methylphenylmaleimide, N-bromophenylmaleimide, N-naphthylmaleimide, N-laurylmaleimide, 2-hydroxyethylmaleimide, N-hydroxyphenylmaleimide, N-methoxyphenylmaleimide, N-carboxyphenyl Maleimide, N-nitrophenylmale(mi)'
etc., and one or more types of these can be used. Compound (4) is a copolymer (1
) 0.5 to 60% by weight, preferably 10 to 50% by weight
Use the ratio. The amount of compound (A) used is 0.5
If it is less than 60% by weight, sufficient heat resistance cannot be imparted to the resulting resin composition, and if it is more than 60% by weight, the molding processability of the resulting resin composition or the vinyl chloride polymer (
Since the miscibility with n) becomes poor, both are unfavorable.

The methacrylic acid ester monomer) contains at least 50% by weight of methyl methacrylate, and is composed of methyl methacrylate alone or methyl methacrylate in the above specified range and 13 or more other methacrylate esters. Can be used in combination with. Other methacrylic esters are not particularly specified, but methacrylic esters of alcohols having 2 to 18 carbon atoms including cyclohexyl alcohol and benzyl alcohol are particularly preferred, such as ethyl methacrylate, propyl methacrylate, inglovir methacrylate, and methacrylate. butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, amyl methacrylate, isoamyl methacrylate,
Octyl methacrylate, 2-ethylhexyl methacrylate, tesyl methacrylate, lauryl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, 2-phenoxyethyl methacrylate, 3-phenylpropyl methacrylate, etc., among which 1 A species or two or more species may be used. in the monomer) is in the copolymer (
In 1), it is used in a proportion of 40 to 99.5% by weight, preferably 45 to 80% by weight.

If the amount of monomer (B) used is less than 40% by weight, the weather resistance and moldability of the resulting resin composition will decrease, and
．． If the amount is more than 5% by weight, sufficient heat resistance cannot be imparted to the resulting resin composition, so both are not preferred.

In the use of monomer 03>, methacrylic esters other than methyl methacrylate, such as butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, lauryl methacrylate, benzyl methacrylate, etc. When used in combination, it is preferable because a resin composition with improved weather resistance, water resistance, or impact resistance and excellent dimensional stability can be obtained.

In obtaining the copolymer (1), if necessary, other monomers that can be copolymerized with the maleimide compound or the methacrylic acid ester monomer in a proportion not exceeding 50% by weight in the copolymer superpolymer (1) (C) can be used in combination.

Other copolymerizable monomers (C) include styrene, α
- Vinyl aromatics such as methylstyrene, paramethylstyrene, vinyltoluene, isopropenylstyrene, chlorstyrene; 7-crylonitrile, methacrylonitrile,
Eta/90 nitrile, phenyl acrylonitrile? ! '
% Saturated nitriles; acrylic esters having an alkyl group having 1 to 18 carbon atoms, including a cycloalkyl group and a benzyl group, such as methyl acrylate, ethyl acrylate, butyl acrylate, inobutyl acrylate, and tertiary butyl acrylate. , amyl acrylate, isoamyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, decyl acrylate, lauryl acrylate, cyclohexyl acrylate, benzyl acrylate, and the like. Furthermore, olefins such as ethylene, propylene, isobutylene, and diisobutylene; dienes such as butadiene and isoprene; vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide, and vinyl fluoride; methyl vinyl ether, phthyl vinyl ether, etc. Vinyl ethers: Vinyl acetate, vinyl propionate Vinyl esters of monocarboxylic acids: Allyl esters of saturated aliphatic monocarboxylic acids such as allyl acetate and allyl propionate, or methanacrylate, divinylbenzene, diallyl phthalate, trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, di(meth)acrylate of ethylene oxide or propylene oxide adducts of bisphenols,
Di(meth)acrylates of ethylene oxide or propylene oxide adducts of halogenated bisphenols, tri(meth)acrylates of incyanurate, di- or tri(meth)acrylates of ethylene oxide or propylene oxide adducts of isocyanurates, etc. Polyvalent (meth)acrylates; polyvalent acrylates such as triallylisocyanurate; and further glycidyl (meth)acrylates;
Examples include acrylate, allyl glycidyl ether, (meth)acrylic acid, itaconic acid, maleic acid, 7-malic acid, or half-esterified products thereof, and depending on the purpose, 1 or 28 or more are used; The amount to be used may be selected within a range that does not depart from the purpose of the present invention.

The vinyl chloride polymer (II) used in the present invention is a vinyl chloride copolymer containing 80 weight or more of a vinyl chloride component, or a chlorinated vinyl chloride copolymer obtained by further adding chlorine to the copolymer, Used alone or in combination.

The method for producing the thermoplastic resin composition of the present invention includes:
Although not particularly limited, conventionally known methods such as simply mechanically mixing polymers, suspension polymerization, emulsion polymerization, bulk polymerization, or a combination of these methods as appropriate can be employed.

For example, suspension polymerization, bulk polymerization, etc. After mixing the obtained copolymer (1) and polymer (II), the percentage is 150 to 300%.
A method of preparing a thermoplastic resin composition by melting, cross-wiring, and extrusion at a temperature of °C: Presence of the copolymer (1) in the monomer mixture used to produce the polymer (If), Bulk polymerization, suspension polymerization or emulsion polymerization in an aqueous medium Φ containing a suspension stabilizer; polymer (II) is present in the monomer mixture constituting copolymer (1), and bulk polymerization is carried out. , suspension polymerization or emulsion polymerization method; emulsion polymerization of the monomer mixture used to produce copolymer (1), and then producing polymer (II) in the obtained emulsion copolymer. Examples include a method of adding and polymerizing monomers to be used for producing a uniform and highly dispersible emulsion, followed by coagulation, washing with water, and drying to obtain a powdery resin composition.

The polymerization reaction employed to produce the thermoplastic resin composition of the present invention is carried out under autogenous pressure or under pressure.

It is carried out under an inert gas atmosphere at temperatures ranging from 0°C or lower to 100°C or higher.

The polymerization initiator used during polymerization is a commonly used free radical polymerization initiator, such as oil-soluble or water-soluble peroxides such as benzoyl peroxide, potassium persulfate, ammonium persulfate, hydrogen peroxide, etc. Azo compounds such as azobisisobutyronitrile are suitable. Further, it is also possible to use a reducing agent such as sodium bisulfite, ascorbic acid, or ferrous sulfate in combination to effectively advance monopolymerization.

Suspension stabilizers used during suspension polymerization include commonly used suspension stabilizers 1 such as calcium carbonate, paricum carbonate, magnesium carbonate, polyvinyl alcohol,
An alkali metal salt of a copolymer of methacrylic acid and methacrylic ester may be used.

Emulsifiers used in emulsion polymerization include commonly used emulsifiers 1 Anionic emulsifiers such as potassium oleate, sodium dodecylbenzenesulfonate, and sulfurized sodium lacryl: polyoxyethylene nonylphenol ether, polyoxyethylene sorbitan Nonionic emulsifiers such as esters; cationic emulsifiers such as lacryltrimethylammonium chloride, etc. may be used as appropriate.

The organic solvent used in the solution polymerization is a commonly used organic solvent, such as toluene, xylene, methyl isobutyl ketone, butyl selonorp, dimethyl formamide, 2-methyl pyrrolidone, Tsurpetz÷1oo (
Organic solvents such as those manufactured by Tonen Petrochemical Co., Ltd.) may be used as appropriate.

The outline of the production of the copolymer (I) constituting the resin composition of the present invention will be explained below using a suspension polymerization method as an example.

At least 50% by weight of the maleimide compound (4) and methyl methacrylate are added to an aqueous solution at room temperature or under heating in which a suspension stabilizer such as polyvinyl alcohol is dissolved.
A polymerization initiator (for example, benzoyl peroxide) is added and dissolved in a monomer mixture of the methacrylic acid ester monomers (containing above) and, if necessary, other monomers (C) copolymerizable with these monomers. Pour the mixture into an inert gas (e.g. nitrogen gas)
Add it under ventilation and stirring, make it cloudy, raise the temperature to a predetermined reaction temperature (usually 60 to 100°C) to start polymerization, and maintain the predetermined temperature range for a certain period of time to complete the polymerization. . After the completion of polymerization, the reaction product is subjected to the following steps: cooling, filtration, washing with water, and drying to obtain the desired copolymer (1).

Most of the maleimide compound (A) constituting the copolymer (I) is solid at room temperature, so in some cases it may not completely dissolve in the organic solvent used or other monomers such as methyl methacrylate at room temperature. There is. In such a case, taking the above-mentioned suspension polymerization as an example, a monomer mixture containing no polymerization initiator is added to an aqueous suspension stabilizer solution with stirring,
After that, the temperature is heated to a temperature higher than the solubility of the other monomers in the initial maleimide synthesis to uniformly suspend the mixture, and then a polymerization initiator is added to carry out polymerization to obtain the desired copolymer (1). You can use methods such as:

The molecular weight of the copolymer (1) is not particularly limited, but if it is too high, the moldability of the resin composition may deteriorate,
Also, if it is too low, there will be disadvantages such as poor weather resistance, heat resistance, mechanical properties, etc., so usually s, ooo ~ 2
．． 000,000. Preferably to, ooo to 1.00
0. A value in the range of 0.05 to 0.05 is preferred. Chain transfer agents, such as butyl mercaptan, are commonly used to adjust the molecular weight.

Tertiary dodecyl mercaptan, mercagutoethanol, etc. may be used.

The thermoplastic resin composition of the present invention can be obtained from the copolymer (1) and the vinyl chloride polymer (II) by the various methods described above. ~50% by weight, vinyl chloride polymer (1) so
The ratio is ~95% by weight.

If the proportion of copolymer (1) used is a small amount outside the above range, the resulting resin composition may have insufficient heat resistance and moldability, and the use of copolymer (!) Even if the ratio exceeds the above range and the amount is too large, the effect commensurate with the amount used may not be sufficiently obtained and it may become uneconomical, and the versatility of the resin composition may be impaired, so care must be taken.

Polymer (II) is a post-chlorinated vinyl chloride polymer.

In this case, the resin composition of the present invention has excellent heat resistance, moldability, etc., and does not have drawbacks such as a decrease in heat resistance unlike conventional compositions, and can fully exhibit its original characteristics.

1. Conventionally known additives may be added to the thermoplastic resin composition of the present invention within the range that does not impair the object of the present invention, such as polybutadiene or butadiene copolymers 15 to 80 containing 50% by weight or more of butadiene. 85 to 20 tt parts of a monomer mixture consisting of one or more monomers selected from acrylic esters, methacrylic esters, and vinyl cyanide compounds, and an aromatic vinyl compound and optionally a maleimide compound; or acrylic acid alkyl ester 10.
0 to BO weight %, a monomer copolymerizable with it 0 to 20 weight t, and a crosslinkable single tray appropriate amount of a copolymer 15 to 80%
Meta-acrylic acid ester in the presence of parts by weight.

A graft copolymer prepared by copolymerizing 20 to 85 parts by weight of a monomer mixture consisting of an acrylic acid alkyl ester, an aromatic vinyl compound, a vinyl cyanide compound, and if necessary a maleimide compound may be used in combination. These graft copolymers are manufactured using known methods, generally emulsion polymerization.

In addition, a copolymer mainly composed of methacrylic acid ester is used as a processing aid, and in some cases, vinyl chloride polymer (It) is used as a processing aid.
It may also be used as a plasticizer.

Examples of other additives include phthalic acid, trimellitic acid,
Plasticizers such as octyl ester of pyromellitic acid; Stabilizers such as diptyltin dimaleate, lead stearate, zinc stearate; Mold release agents such as stearic acid and calcium stearate; Fillers such as calcium carbonate and titanium oxide; bleached belly,
Examples include ultraviolet absorbers.

(Effects of the Invention) The thermoplastic resin composition of the present invention has excellent heat resistance, weather resistance, water resistance, impact resistance, and moldability, so it can be used as a general-purpose engineering plastic for building materials, automobile parts, electrical equipment parts, etc. It is also used in special fields such as diskettes.

Next, the present invention will be explained in more detail with reference to Examples, but it goes without saying that the present invention is not limited to these Examples. In the examples, "parts" and "chi" indicate parts by weight and % by weight, respectively.

Reference Example 1 550 parts of deionized water and 0.28 parts of polyvinyl alcohol (Gohsenol GH-20, manufactured by Nippon Gosei ■) were charged into an IAt stainless steel four-loaf flask equipped with a stirrer, and heated to 80°C under a nitrogen gas atmosphere. After completely dissolving the polyvinyl alcohol, the mixture was cooled to 50°C.

Weighed 168 parts of methyl methacrylate and 72 parts of cyclohexylmaleimide into a separate container, heated it to about 40°C to dissolve the cyclohexylmaleimide, and then added and dissolved 9.6 parts of benzoyl peroxide to obtain a uniform monomer content. A body solution was obtained.

The entire amount of the obtained monomer solution was added to 4 lower 2 SCs and held for 10 minutes under stirring at 400 rpnlL in a nitrogen gas atmosphere to form a suspension state, and then the internal temperature was raised to 80°C. The temperature was then maintained at this temperature for 7 hours to complete the polymerization. The resulting aqueous suspension was subjected to Zoo mesh F.
After covering with a cloth and thoroughly washing with deionized water, the mixture was dried in a hot air circulation dryer at 90°C to obtain about 220 parts of granular copolymer (1) with a diameter of about 0.5 m. The molecular weight (peak value determined by GPC) of this copolymer (1) was about 170.000.

Reference Examples 2 to 7 The same operations as in Reference Example 1 were repeated, except that 240 parts of a monomer mixture having the composition shown in Table 1 was used instead of methyl methacrylate and cyclohexylmaleimide in Reference Example IK. Copolymers (2) to (7) having molecules i1 (peak values determined by GPC) shown in Table 1 were obtained.

Examples 1 to 3 Copolymer (1) obtained in Reference Example 1 and vinyl chloride resin (
Sumi IJ Tsu) 8X-11P, manufactured by Sumitomo Chemical ■, polymerization degree ro
Resin compositions (1) to (3) having the formulations shown in Table 2 were prepared using So. The obtained resin composition (1
) to (3) were kneaded for 5 minutes using a hot roll with a diameter of 8 inches heated to a surface temperature of 190°C to obtain a sheet-like resin composition, which was then kneaded using a flat plate press at 190°C and 100°C.
A test piece was prepared by press molding for 10 minutes under a pressure of 9/ci.

The results are shown in Table 2, and it was found that the resin composition of the present invention showed good results. Table 2 also shows the evaluation results of the workability of the resin compositions in each example when hot rolls were mixed, and the results were good without any problems.

The method for measuring heat distortion temperature is A8TM D-648,
Izotsu impact strength is in accordance with human STMD-256, and accelerated weather resistance is 1000 on a sunshine type etherometer.
By observing the appearance after time irradiation, ○: Good;
Δ: Slightly poor, ×: Poor, workability can be determined by observing the hot roll cross-wire state, O: Good, Δ: Slightly poor.
×: Evaluated as bad.

Comparative Example 1 A comparative resin composition (1) was prepared in the same manner as in Example 1 except that the copolymer (1) in Example 1 was not used, and then test pieces were prepared and evaluated in the same manner. went. The results are shown in Table 2. Comparative resin composition (1) showed inferior results compared to resin compositions (1) to (3) obtained in Examples 1 to 3.

Comparative Example 2 A comparative copolymer (molecular weight peak value A comparative resin composition (170.000) was prepared with the same composition as in Example 1 except that the obtained comparative copolymer was used in place of copolymer (1) in Example IK. 2) was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

Comparative resin composition (2) obtained in Comparative Example 2 showed inferior results compared to resin compositions (1) to (3).

Examples 4 to 9 Same composition as Example 1 except that copolymers (2) to (7) obtained in Reference Examples 2 to 7 were used in place of copolymer (1) in Example 1. After preparing resin compositions (4) to (9), test pieces were prepared and evaluated in the same manner. The results are shown in Table 3.

Table 3

Claims (1)

[Claims] 1. General formula ▲ Numerical formula, chemical formula, table, etc. ▼ (In the formula, R is hydrogen, alkyl having 1 to 15 carbon atoms, cycloalkyl, aryl group, or substituted aryl group.) The maleimide compound (A) represented by 0.5 to 60% by weight and the methacrylic acid ester monomer (B) containing at least 50% by weight of methyl methacrylate from 99.5 to 60% by weight.
40% by weight and other monomers copolymerizable with these (C)
Copolymer (I) obtained from 0 to 50% by weight (however, the total of components (A), (B) and (C) is 100% by weight) and vinyl chloride polymer (II). A thermoplastic resin composition with excellent heat resistance, weather resistance, impact resistance, and moldability.