JPH02142844A - Vinyl chloride resin composition - Google Patents

Abstract

PURPOSE:To obtain the title composition improved in heat distortion resistance, moldability, impact resistance and heat stability by mixing a vinyl chloride/N- substituted maleimide copolymer with a specified stabilizer and a specified maleimide copolymer. CONSTITUTION:50-95wt.% vinyl chloride copolymer (A) obtained by polymerizing 50-99wt.% vinyl chloride with 1-50wt.% N-substituted maleimide compound of the formula [wherein R<1> is a 1-30C (un)substituted aliphatic, alicyclic or aromatic hydrocarbon group; R<2-3> are each H, F, Cl, Br, cyano or a 3C or lower alkyl] at 20-80 deg.C in the presence of a free radical generating catalyst is blended with at least 0.5 pt.wt., per 100 pts.wt. component A, at least one stabilizer (B) selected from among organotin and lead stabilizers (e.g., dimethyltin mercaptide) and 5-50wt.% maleimide copolymer (C) of an MW of 5000-2000000, obtained by copolymerizing 15-60wt.% N-substituted maleimide compound with 20-50wt.% methyl methacrylate, 0-50wt.% styrene and 0-30wt.% polymerizable monomers copolymerizable therewith (e.g., butadiene).

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a vinyl chloride resin composition useful as plastic molded products that are widely used in various industrial fields, particularly for improving heat deformation resistance, thermal stability, and mechanical properties. The present invention relates to a vinyl chloride resin composition that has excellent physical strength, dimensional stability, weather resistance, moldability, etc.

(Prior Art and Problems to be Solved by the Invention) It is known that the heat deformation resistance of vinyl chloride resins is poor in polyvinyl chloride, but good in post-chlorinated vinyl chloride. However, after this, chlorinated vinyl chloride has poor thermal stability and impact resistance, generates acidic gas during processing and corrodes equipment, and has inferior moldability compared to polyvinyl chloride. There are drawbacks.

Therefore, vinyl chloride monomer and N-
Substituted maleimide compound r) (wherein R1 is a substituted or unsubstituted aliphatic, alicyclic, or aromatic hydrocarbon group having 1 to 30 carbon atoms, R2
and R3 are the same or different from each other, hydrogen, fluorine,
A vinyl chloride-N-substituted maleimide resin composition based on a copolymer consisting of a chlorine or bromine atom, a cyano group, or an alkyl group having 3 or less carbon atoms has been proposed, but this resin Although it is superior to post-chlorinated vinyl chloride in terms of processability, it is slightly inferior in heat resistance, and it is inferior to polyvinyl chloride in processability, thermal stability, and impact resistance.Therefore, the purpose of the present invention is to: This vinyl chloride-N-substituted maleimide resin composition has been improved to improve heat deformation resistance, moldability,
The present invention aims to provide a novel vinyl chloride-based resin composition from which molded products with good impact resistance and excellent thermal stability can be obtained.

(Means for Solving the Problems) The vinyl chloride resin composition according to the present invention consists of (1) 50 to 99% by weight of structural units derived from vinyl chloride and an N-substituted maleimide compound represented by the general formula vinyl chloride copolymer A containing 1 to 50% by weight of structural units; hydrocarbon group of group R
2 and R3 are the same or different and are hydrogen, fluorine, chlorine or bromine atoms, cyano groups, or alkyl groups having 3 or less carbon atoms) (2) selected from organotin stabilizers and lead stabilizers at least one stabilizer, and (3) 15 to 60% by weight of structural units derived from the N-substituted maleimide compound represented by the above general formula, 20 to 50% by weight of structural units derived from methyl methacrylate, and styrene. Maleimide copolymer B consisting of 0 to 50% by weight of structural units derived from and 0 to 30% by weight of structural units derived from other polymerizable monomers that can be copolymerized with these monomers.
The gist of this paper is that it has been made from , and .

The present invention will be explained in detail below.

The vinyl chloride copolymer A used as component (1) in the composition of the present invention is obtained from a vinyl chloride monomer and an N-substituted maleimide compound represented by the above general formula. Specific examples of N-substituted maleimide compounds include N-methylmaleimide, N-ethylmaleimide, Nn-propylmaleimide, N-isopropylmaleimide, Nn-butylmaleimide, N-t
-Butylmaleimide, N-hexylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, N
Hydroxyphenylmaleimide, N-(p+rrzo)
Hydroxyphenylmaleimide, N-(p,m,o)-
Methoxyphenylmaleimide, N-(P+m+O)-chlorophenylmaleimide, N-(p+m+o)-carboxyphenylmaleimide, N-(p,m,o)-nitrophenylmaleimide, N-laurylmaleimide, N-bicyclo-(2, Examples include 2,1)-hebutan-1-yl-3methylmaleimide, N-9,10-ethano-9,10-dihydroanthracen-2-ylmaleimide, and N-triphenylmethylbenzylmaleimide. , among these, methyl, 1-butyl, cyclohexyl, bicyclo-(2,2,1)hebutan-1-yl-3-methyl, 9,10-ethano-9°10-dihydroanthracenyl , triphenylmethylbenzyl and the like are particularly preferred.

Copolymer A consisting of this vinyl chloride monomer and the N-substituted maleimide compound has a structural unit derived from the vinyl chloride monomer in an amount of 50 to 99% by weight, preferably 70 to 95% by weight, It is necessary that the constituent units derived from the N-substituted maleimide compound account for 1 to 50% by weight, preferably 5 to 30% by weight. If the content of the structural unit derived from the N-substituted maleimide compound is less than 1% by weight, the heat resistance of the copolymer will not be sufficiently improved, and if it exceeds 50% by weight, the melting temperature of the copolymer will be too high, resulting in poor moldability. worsen.

In addition, in the production of this copolymer, if necessary, other polymerizable monomers and at least one polymer that can be craft-polymerized with vinyl chloride are added, and the structural units derived from these are added to the resulting copolymer. It can be used in amounts such that during coalescence it is less than 30% by weight, preferably less than 15% by weight. If it exceeds 30% by weight, it is not preferable because the inherent properties of vinyl chloride resin, such as mechanical strength and durability, are lost.

Other polymerizable monomers used here include vinyl esters such as vinyl acetate, vinyl propionate, vinyl caproate, vinyl laurate, and vinyl stearate;
Olefins such as ethylene, propylene, and isobutylene; alkyl vinyl ethers such as isobutyl vinyl ether, octyl vinyl ether, dodecyl vinyl ether, and phenyl vinyl ether; halogenated olefins such as vinylidene chloride, vinyl fluoride, propylene chloride, and vinyl bromide; ethyl acrylate; Acrylic acid and methacrylic acid esters such as n-butyl acrylate, n-butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, stearyl methacrylate; acrylic acid, methacrylic acid, crotonic acid, acrylonitrile, maleic anhydride , acrylic derivatives such as itaconic anhydride; and the like, and these can be used alone or in combination of two or more.

In addition, examples of polymers that can be graft-polymerized with vinyl chloride include ethylene-vinyl acetate copolymer (EVA), ethylene-ethyl acrylate copolymer, chlorinated polyethylene, polyurethane, polybutadiene-styrene-methyl methacrylate (MBS), Examples include polybutadiene-acrylonitrile-(α-methyl)styrene (ABS), polybutyl acrylate, butyl rubber, polystyrene, styrene-butadiene copolymer, and crosslinked acrylic rubber.

This vinyl chloride copolymer A is produced by adding the above components in the presence of a free radical-generating catalyst at 20 to 80°C by any method such as bulk polymerization, suspension polymerization, or emulsion polymerization. However, it is industrially and economically advantageous to use the suspension polymerization method.

The free radical generating catalyst may be one conventionally used in vinyl chloride polymerization, such as decanoyl peroxide, lauroyl peroxide, benzoyl peroxide, diisopropyl peroxydicarbonate, ethylhexyl peroxide, carbonate toxyethyl peroxydicarbonate; peroxycarbonate compounds such as t-butyl peroxypivalate, t-hexyl peroxypivalate, t-butyl peroxyneodecanate, α-cumyl peroxyneodecanate; Ester compounds; Peroxides such as acetylcyclohexylsulfonyl peroxide, 2,4.4-trimethylpentyl-2-paoxyphenoxyacetate, 3,5.5-trimethylhexanoyl peroxide; α, α′
-Azo compounds such as azobisisobutyronitrile, α,α′-azobis-2,4-dimethylvaleronitrile, α,α′-azobis(4-methoxy-2,4-dimethylvaleronitrile); and potassium persulfate , ammonium persulfate, hydrogen peroxide, etc., and these can be used alone or in combination of two or more.

In addition, in the above suspension polymerization, commonly used dispersion aids such as methyl cellulose, ethyl cellulose,
Water-soluble cellulose ethers such as hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, and carboxymethylcellulose; synthetic nine-molecular compounds such as fully or partially saponified polyvinyl alcohol, acrylic acid polymers, polyvinylpyrrolidone, and maleic anhydride-vinyl acetate copolymers; starch,
Natural polymeric substances such as gelatin; oil-soluble emulsifiers such as sorbitan monolaurate-1, sorbitan triolate, glycerin tristearate, and ethylene oxide propylene oxide block copolymer; polyoxyethylene sorbitan monolaurate, polyoxyethylene glycerin oleum Water-soluble emulsifiers such as sodium laurate and sodium laurate may be used alone or in combination of two or more.

Furthermore, in this polymerization system, a polymerization degree regulator, a chain transfer agent, and a p] which are used as appropriate for vinyl chloride polymerization are added.
(It is also optional to add regulators, gelling improvers, antistatic agents, antioxidants, scale inhibitors, etc.)

The other conditions for this polymerization and the method of charging the aqueous medium, vinyl chloride monomer, other comonomers, dispersion aids, polymerization initiator, etc. to the polymerization vessel can be carried out in the same manner as conventional methods. The polymerization conditions such as the charging ratio and polymerization temperature may also be the same).

Of the at least one stabilizer selected from organotin stabilizers and lead stabilizers used as component (2) in the vinyl chloride resin composition of the present invention, first, as the organotin stabilizer, for example, , di-n-alkyltin mercaptide such as dimethyltin mercaptide, di-n-alkyltin dilaurate, dibutyltin dimaleate, dibutyltin lauryl mercaptide, dioctyl t4-s, s'-bis-(isooctyl-mercaptoacetate), dibutyl Examples include tin bisisooctylthioglycolate, di(n-octyl)tin maleate polymer, dibutyltin mercaptopropionate, and the like. Among these, dimethyltin mercaptide and a combination of dimethyltin mercaptide and dibutyltin dimaleate are preferred.

In addition, examples of lead-based stabilizers include tribasic sulfate,
Organic and inorganic lead compounds such as dibasic lead phosphite, basic lead sulfite, dibasic lead phthalate, dibasic lead stearate, stearate, silica gel coprecipitated lead silicate, etc. are mentioned.

These organotin-based and lead-based stabilizers may be used alone or in combination of two or more. The stabilizer used as component (2) is preferably used in an amount of 0.5 parts by weight or more, particularly 1 to 20 parts by weight, per 100 parts by weight of vinyl chloride copolymer A, component (1). If the amount of the stabilizer is too small, the effects of the present invention will be difficult to exhibit, while if the amount is too large, the heat deformation resistance may be impaired.

As mentioned above, maleimide copolymer B used as component (3) in the composition of the present invention is composed of an N-substituted maleimide compound, methyl methacrylate, styrene added thereto as necessary, and these. It consists of a monomer and other polymerizable monomers that can be copolymerized, and the proportion of each component is 15 to 60% by weight as a structural unit derived from the N-substituted maleimide compound represented by the above general formula. %
, preferably 30 to 50% by weight, 20 to 50% by weight as structural units derived from methyl methacrylate, preferably 30 to 40% by weight, 0 to 50% by weight as structural units derived from styrene, preferably 45% by weight or less The content of structural units derived from other polymerizable monomers that can be copolymerized with these monomers is required to be 0 to 30% by weight, preferably 15% by weight or less.

The N-substituted maleimide compound as the first component of the maleimide copolymer B is the same as the N-substituted maleimide compound used in the vinyl chloride copolymer A described above. If the structural unit derived from this compound is less than 15% by weight, sufficient heat resistance will not be imparted to the resulting resin composition;
If it exceeds % by weight, the molding processability of the resulting resin composition and the miscibility of the present copolymer B with the vinyl chloride copolymer A will deteriorate, which is not preferable. If the structural unit derived from methyl methacrylate as the second component is less than 20% by weight, the molding processability of the resulting resin composition will decrease, and if it exceeds 50% by weight, the resulting resin composition will not have sufficient heat resistance. This is not preferable as it will not be possible to provide the option. If the third component, the structural unit derived from styrene, exceeds 50% by weight, the mechanical strength of the resulting resin composition will decrease, which is not preferable. In addition,
This maleimide copolymer B containing the three components of these N-substituted maleimide compounds, methyl methacrylate, and styrene in the above proportions is particularly effective in improving processability and impact resistance. .

The vinyl chloride resin composition according to the present invention comprises this copolymer B.
By blending the vinyl chloride copolymer A, its appearance is not impaired or the excellent properties provided by the vinyl chloride copolymer A are not impaired, and it has excellent heat resistance, impact resistance, moldability, etc. can be obtained as

When the amount of structural units derived from other polymerizable monomers copolymerizable with the above-mentioned three components of the fourth component exceeds 30% by weight, the heat resistance, impact resistance, moldability, etc. of the resin composition according to the present invention may deteriorate. This is undesirable as it may cause loss of quality.

Examples of such polymerizable monomers include methyl acrylate, ethyl (meth)acrylate, propyl (meth)acrylate,
Acrylate, butyl (meth)acrylate, t-butyl (meth)acrylate, amyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, cyclohexyl (meth)acrylate, ethylene glycol (meth)acrylic acid esters other than methyl methacrylate such as di(meth)acrylate, diethylene glycol di(meth)acrylate, and trimethylolpropane tri(meth)acrylate; α-methylstyrene;
Alkylstyrenes such as paramethylstyrene and isopropenylstyrene; unsaturated nitriles such as (meth)acrylonitrile; olefins such as ethylene and propylene; dienes such as butadiene and isoprene; vinyl esters such as vinyl acetate; etc., and one or more types selected from these can be used.

As these polymerizable monomers, butadiene, acrylonitrile, or isoprene is added to copolymer B in an amount of 1 to 30%.
It is preferable to use it in an amount of 1 to 15% by weight, in particular, since impact resistance can be significantly improved without reducing heat resistance.

The polymerization reaction employed to produce maleimide copolymer B can be carried out at a predetermined temperature, that is, from 0 to 100°C, under autogenous pressure or increased pressure, in an inert gas atmosphere.

The polymerization initiator used during polymerization is a commonly used free radical polymerization initiator, such as peroxides such as benzoyl peroxide, potassium persulfate, ammonium persulfate, hydrogen peroxide, and azobisisobutyronitrile. Azo compounds such as are suitable.

Examples of suspension stabilizers used during suspension polymerization include calcium carbonate, barium carbonate, magnesium carbonate, polyvinyl alcohol, and alkali metal salts of copolymers of methacrylic acid and methacrylic ester.

Examples of emulsifiers used during emulsion polymerization include anionic emulsifiers such as potassium oleate, sodium dodecylbenzenesulfonate, and sodium lauryl sulfate; nonionic emulsifiers such as polyoxyethylene nonylphenol ether and polyoxyethylene sorbitan ester. Emulsifiers; cationic emulsifiers such as lauryltrimethylammonium chloride; and the like.

Examples of organic solvents used during solution polymerization include toluene, xylene, methyl isobutyl ketone, butyl cellosolve, dimethylformamide, 2-methylpyrrolidone, and the like, and are appropriately selected from these.

Next, the outline of the production of this copolymer 13 will be explained using a suspension polymerization method as an example.

A homogeneous mixed solution obtained by adding and dissolving a monomer mixture of a maleimide compound and methyl methacrylate and a polymerization initiator such as benzoyl peroxide into a heated aqueous solution in which a suspension stabilizer is dissolved is mixed with an unaltered mixture. After adding under active gas ventilation and stirring to create a suspended state, the temperature is raised to a predetermined reaction temperature of around 80°C to initiate polymerization, and the predetermined temperature range is maintained for a certain period of time to complete polymerization. . In the obtained polymer,
A mixture of styrene and other polymerizable monomers that can be copolymerized therewith, and a polymerization initiator are mixed and added under inert gas ventilation and stirring to form a suspension, and then the mixture is heated to a predetermined reaction temperature. Polymerization is initiated by raising the temperature to , and the polymerization is completed by maintaining a predetermined temperature range for a certain period of time. After the polymerization is completed, the reaction product is subjected to cooling, filtration, water washing, and drying steps to obtain the desired copolymer B.

Since the maleimide compound constituting copolymer B is solid at room temperature, it may not be completely soluble in the organic solvent used or other monomers such as methyl methacrylate and styrene at room temperature in some cases.

In such a case, taking the above-mentioned suspension polymerization as an example, firstly, only the monomer mixture is added to an aqueous suspension stabilizer solution while stirring, and then the maleimide compound is added to a solution with a solubility higher than that of the other monomers. A method may be adopted in which the desired copolymer B is obtained by heating the mixture to a temperature of 100 to 100%, uniformly suspending the mixture, and then adding a polymerization initiator to carry out polymerization.

The molecular weight of copolymer B is not particularly limited, but if it is too high, the molding processability of the resin composition will be poor, and if it is too low, it will have disadvantages such as poor corrosion resistance, heat resistance, mechanical properties, etc. Usually 5,000 to 2,0
00,000, preferably 10,000 to 1.000,
A range of 000 is preferred.

The blending ratio of the vinyl chloride copolymer A and the maleimide copolymer B in the resin composition of the present invention is 50 to 95% by weight of the copolymer A and the maleimide copolymer B
It is preferably 5 to 50% by weight. If the proportion of copolymer B used is less than this range, the resulting resin composition may have insufficient heat resistance and moldability, and even if it exceeds this range, it may not be sufficient for the amount used. This is undesirable because it is uneconomical and the versatility of the resin composition is impaired.

In addition to the above-mentioned components (1) to (3), the composition of the present invention may also contain lubricants, processing aids, antistatic agents, and fillers, if necessary, in view of the processability of the composition and the required physical properties of the molded product. , antioxidants, flame retardants, ultraviolet absorbers, colorants, modifiers, smoke suppressants, etc. can be added within the range that does not impair the effects of the present invention.

Examples of lubricants include metal salts such as magnesium, aluminum, calcium, cadmium, lead, barium, and lithium such as lauric acid, stearic acid, oleic acid, ethylhexoic acid, ricinoleic acid, and naphthenic acid; organotin fatty acid salts; Fatty acids and their esters; amides; higher ketones; higher alcohols; paraffin wax; polyethylene wax; acrylic wax; natural wax; Monoglycerides of fatty acids such as stearic acid are preferable because they do not adversely affect thermal stability.

Processing aids include acrylonitrile-styrene copolymer (AS), methyl methacrylate-styrene copolymer (MS), acrylonitrile-butadiene-styrene copolymer (ABS), and methyl methacrylate-butadiene-styrene copolymer (MBS). ), paraloid, epichlorohydrin, polymethacrylate, polybutadiene, polystyrene, polyethylene, acrylate polymer, ethylene-vinyl acetate copolymer, and the like.

As the antistatic agent, various cationic, anionic, nonionic, or amphoteric surfactants are used.

In addition, heat resistance improvers such as acrylonitrile-α-methylstyrene-butadiene copolymer, PMMA and acrylic acid ester copolymer, or the above-mentioned additives that are blended with other general vinyl chloride resins are added. Good too.

Furthermore, the composition of the present invention may contain the above (1) as necessary.
) Vinyl chloride resins other than the vinyl chloride copolymer A of the component can be used in combination. This vinyl chloride resin has
For example, in addition to vinyl chloride homocopolymers, copolymers of vinyl chloride and ethylene, propylene, etc.
Examples include vinyl acetate copolymers, ethylene-ethyl acrylate copolymers, multi-component copolymers made by graft copolymerizing vinyl chloride onto ethylene copolymers such as chlorinated polyethylene, and blends of two or more of these. It will be done.

(Examples) Hereinafter, specific aspects of the present invention will be explained using Examples and Comparative Examples, but the present invention is not limited by these Examples.

Examples 1 to 14 and Comparative Examples 1 to 6 In each example, vinyl chloride copolymer A was N as shown in Table 1.
-Vinyl chloride-N-substituted maleimide copolymers 1 to 2 containing a substituted maleimide component were used, and as maleimide copolymer B, N-substituted maleimide, methyl methacrylate, styrene, and other components shown in Table 2 were used. A copolymer containing 1-fx was used.

Additives such as stabilizers, metal soaps, and lubricants were added to these copolymers A and B in the proportions shown in Table 3, and Examples 1 to 1 were prepared.
4 and Comparative Examples 1 to 7 were prepared.

Each of the obtained resin compositions was kneaded for 5 minutes using a heated roll with a diameter of 6 inches heated to a surface temperature of 200°C, and after evaluating the suitability of the roll at the time of cross-wiring using the following criteria, it was formed into a sheet. , further at 180°C at 2000°C using a flat plate press.
A test piece was prepared by press molding for 8 minutes under a pressure of kg/d. After observing the appearance of this test piece, it was used to measure the Izot impact strength using a method based on JIS K-7110, and the VICA 'l' needle temperature using a method based on JIS K-7110.
It was measured by a method similar to the -7206A method, and the results are also listed in Table 3.

・Role suitability judgment criteria: Excellent...Ol Fairly good...
・・・・△Good ・・・・・・・・・Ol Bad
・・・・・・・・・×The appearance of the test pieces made from the resin composition of the present invention was good, and as shown in Table 3, good results were also obtained in each of the other test measurements. All of the resin compositions as comparative examples had inferior results compared to these.

(Effects of the Invention) The vinyl chloride resin composition of the present invention has excellent appearance, heat resistance, impact resistance, moldability, etc., and is therefore widely used in the fields of plastic products such as industrial and building materials.

Claims (1)

[Scope of Claims] 1. (1) A chloride containing 50 to 99% by weight of structural units derived from vinyl chloride and 1 to 50% by weight of structural units derived from an N-substituted maleimide compound represented by the following general formula. Vinyl copolymer A and general formula: ▲Mathematical formula, chemical formula, table, etc.▼ (In the formula, R^1 is a substituted or unsubstituted aliphatic, alicyclic, or aromatic group having 1 to 30 carbon atoms. hydrocarbon group, R
^2 and R^3 are the same or different and are a hydrogen, fluorine, chlorine or bromine atom, a cyano group, or an alkyl group having 3 or less carbon atoms) (2) Organotin stabilizer and lead stabilizer and (3) 15 to 60% by weight of structural units derived from the N-substituted maleimide compound represented by the above general formula and 20 to 50% by weight of structural units derived from methyl methacrylate. , a maleimide copolymer B containing 0 to 50% by weight of structural units derived from styrene and 0 to 30% by weight of structural units derived from other polymerizable monomers that can be copolymerized with these monomers. , A vinyl chloride resin composition consisting of. 2. The vinyl chloride resin composition according to claim 1, wherein the other polymerizable monomer is one or more of butadiene, acrylonitrile, and isoprene. 3. In the composition, vinyl chloride copolymer A is 50 to 9
2. The vinyl chloride resin composition according to claim 1, wherein the vinyl chloride resin composition contains 5% by weight of the maleimide copolymer B, 5 to 50% by weight of the maleimide copolymer B, and an effective amount of the stabilizer.