JPH0827233A - Vinylchloride-based resin - Google Patents

Abstract

PURPOSE:To obtain a vinylchloride-based resin excellent in impact resistance and mechanical strength. CONSTITUTION:This vinylchloride-based resin is obtained by graft copolymerizing 1-30wt.% acryl-based copolymer latex with 70-99-wt.% of vinylchloride. The acryl-based copolymer latex is obtained by graft copolymerizing 1-50wt.% of a mixture consisting of (A) 100 pts.wt. vinyl monomer of which homopolymer has >=-20 deg.C glass transition temperature and (B) 0.1-20 pts.wt. multi-functional monomer with 50-99wt.% acryl-based copolymer, and the acryl-based copolymer is obtained by copolymerization of (C) 100 pts.wt. acryl-based monomer consisting of an alkyl(metha)acrylate of which homopolymer has <-20 deg.C glass transition temperature as a major component with (B) 0.1-10 pts.wt. multi-functional monomer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vinyl chloride resin having excellent impact resistance and mechanical strength.

[0002]

2. Description of the Related Art Vinyl chloride resins are used in many applications as materials having excellent mechanical strength, weather resistance, chemical resistance, etc., but they have drawbacks in impact resistance.
Various improvement methods have been proposed, and for example, a method for producing a vinyl chloride resin excellent in impact resistance and weather resistance by graft-copolymerizing vinyl chloride on an acrylic copolymer has been reported (JP (Sho 60-255813).

[0003]

However, the vinyl chloride resin obtained by the above-mentioned manufacturing method has a problem that mechanical strength such as tensile strength is lowered as impact resistance is improved.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a vinyl chloride resin having excellent impact resistance and mechanical strength.

[0005]

The vinyl chloride resin of the present invention is obtained by graft-copolymerizing vinyl chloride onto an acrylic copolymer latex. At that time, the acrylic copolymer resin used in the present invention is used. The combined latex is (A)
It is obtained by graft-copolymerizing a mixed monomer consisting of a vinyl monomer (B) having a glass transition temperature of -20 ° C or higher and a polyfunctional monomer (B) with an acrylic copolymer.

Examples of the vinyl monomer (A) include methyl (meth) acrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl (meth) acrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate,
t-butyl (meth) acrylate, n-hexyl methacrylate, cyclohexyl (meth) acrylate, lauryl acrylate, myristyl (meth) acrylate,
Palmityl (meth) acrylate, stearyl (meth)
Alkyl (meth) acrylate such as acrylate, 2-
Examples thereof include polar group-containing vinyl monomers such as hydroxyethyl (meth) acrylate, 2-hydroxypropyl methacrylate, and 2-acryloyloxyethyl phthalic acid, styrene-based monomers such as styrene and α-methylstyrene, and acrylonitrile. These may be used alone or Two or more kinds can be used in combination.

The polyfunctional monomer (B) makes it difficult for particles to coalesce by cross-linking the polymer grafted on the acrylic copolymer, and further improves the impact resistance of the resulting vinyl chloride resin. It is added for the purpose of improving, for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, diallyl phthalate, diallyl malate, trimethylolpropane di (meth) acrylate, triethylene glycol di (meth) acrylate, Trimethylolpropane tri (meth) acrylate, ethylene oxide modified trimethylolpropane tri (meth) acrylate, and other polyfunctional (meth) acrylates, pentaerythritol tetra (meth) acrylate, dipentaerythritol hex (Meth) pentaerythritol-based polyfunctional (meth) acrylates such as acrylate and the like, which may be used singly or in combinations of two or more.

The glass transition temperature of the above homopolymer is -2.
When the amount of the above-mentioned polyfunctional monomer (B) added to 100 parts by weight of the vinyl monomer (A) at 0 ° C. or higher is small, it becomes difficult to obtain the impact resistance of the obtained vinyl chloride resin, and when it is large, the impact resistance becomes large. Since it is difficult to obtain both properties and tensile strength, it is 0.1 to 20 parts by weight, preferably 0.2 to 10 parts by weight.

If the proportion of the above mixed monomer in the above acrylic copolymer latex is small, it is difficult to obtain the tensile strength of the obtained vinyl chloride resin, and if it is too large, it is difficult to obtain the impact resistance. It is 1 to 50% by weight, preferably 5 to 25% by weight.

The acrylic copolymer used in the production of the above acrylic copolymer latex is an acrylic copolymer whose main component is an alkyl (meth) acrylate in which the glass transition temperature of the homopolymer (C) is lower than -20 ° C. It is obtained by copolymerizing a monomer and (B) polyfunctional monomer.

Further, if the proportion of the acrylic copolymer in the acrylic copolymer latex is small, the impact resistance of the vinyl chloride resin obtained is difficult to obtain, and if it is large, the tensile strength is sufficient. 50 to 99% by weight, preferably 75 to 95% by weight,
Is.

The above alkyl (meth) acrylate (C)
Examples thereof include ethyl acrylate, n-propyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, and n.
-Octyl (meth) acrylate, isooctyl acrylate, n-nonyl (meth) acrylate, isononyl acrylate, n-decyl (meth) acrylate, lauryl methacrylate and the like, and these may be used alone or in combination of two or more kinds. Can be done.

The above alkyl (meth) acrylate (C)
When the proportion of the above acrylic monomer in the above is small, it is difficult to obtain the impact resistance of the obtained vinyl chloride resin, so that it is preferably 75% by weight or more.

The acrylic monomer may contain other vinyl monomers copolymerizable with the alkyl (meth) acrylate (C). For example, the glass transition temperature of the acrylic copolymer may be changed. The vinyl monomer (A) described above is suitable for arbitrary adjustment, and these can be used alone or in combination of two or more kinds.

If the proportion of the vinyl monomer (A) in the acrylic monomer is too large, the impact resistance of the vinyl chloride resin obtained will be difficult to obtain.
The following are preferred.

In the same manner as described above, the above-mentioned polyfunctional monomer (B) is used for the purpose of cross-linking the above-mentioned acrylic copolymer to prevent particles from adhering to each other and further improving the impact resistance of the resulting vinyl chloride resin. ) Are added, either alone or 2
Combinations of more than one type can be used.

The amount of the polyfunctional monomer (B) added is
When the amount is small, it is difficult to obtain the impact resistance of the obtained vinyl chloride resin, and when the amount is large, it is difficult to obtain both the impact resistance and the tensile strength.
0.1 to 10 parts by weight, preferably 0.00
2 to 8 parts by weight.

Examples of the method for obtaining the above acrylic copolymer include an emulsion polymerization method and a suspension polymerization method. The emulsion polymerization method is preferable in that the vinyl chloride resin obtained has good impact resistance. preferable. An emulsion dispersant and a polymerization initiator are used in the above emulsion polymerization method.

The above-mentioned emulsifying dispersant is added for the purpose of improving the dispersion stability of the above-mentioned monomer composition in an emulsion and efficiently carrying out the polymerization. For example, an anionic surfactant or a nonionic surfactant is used. , Partially saponified polyvinyl alcohol, cellulose-based dispersants, gelatin, and the like. Particularly, as an anionic surfactant, a higher alcohol sulfate salt (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., trade name “Monogen Y”).
-100 ").

Examples of the above-mentioned polymerization initiator include water-soluble polymerization initiators such as potassium persulfate, ammonium persulfate and hydrogen peroxide solution, organic peroxides such as benzoyl peroxide and lauroyl peroxide, and azobisisobutyrate. Examples thereof include azo initiators such as ronitrile.

Further, in the above emulsion polymerization method, a pH adjusting agent, an antioxidant and the like may be added as required.

The emulsion polymerization methods are roughly classified into three methods, that is, a batch polymerization method, a monomer dropping method and an emulsion dropping method according to the difference in the monomer addition method, but they are not particularly limited. With the batch polymerization method, for example, pure water, an emulsifying dispersant, a polymerization initiator, and the above mixed monomer are added all at once in a jacketed polymerization reactor, and under the conditions of oxygen removal and pressurization by a nitrogen stream, This is a method in which after sufficiently emulsifying by stirring, the inside of the vessel is heated by a jacket to polymerize. Further, the monomer dropping method means, for example, adding pure water, an emulsifying dispersant, and a polymerization initiator in a jacketed polymerization reactor,
Under the conditions of removing oxygen by a nitrogen stream and pressurizing, the inside of the vessel is first heated by a jacket, and then the above-mentioned mixed monomer is added dropwise in a constant amount to gradually polymerize. The emulsion dropping method is, for example, to prepare the emulsified monomer in advance by sufficiently emulsifying the mixed monomer, the emulsifying dispersant, and the pure water by stirring, and then adding the pure water and the polymerization initiator into the jacketed polymerization reactor. Under the conditions of oxygen removal by a nitrogen stream and pressurization, the inside of the vessel is first heated by a jacket, and then the above-mentioned emulsified monomer is added dropwise by a fixed amount to perform polymerization.

The above acrylic copolymer latex was added to a polymerization reactor with a jacket containing an acrylic copolymer obtained by the above emulsion polymerization, followed by a calculated amount of vinyl monomer (A) and polyfunctional monomer (B). It is generally obtained by graft copolymerization using an emulsion polymerization method in which is added and the inside of the vessel is heated again by a jacket, but it can also be obtained by a suspension polymerization method.

When the above acrylic copolymer latex is obtained, an emulsifying dispersant and a polymerization initiator may be optionally added, and a pH adjusting agent, an antioxidant and the like may be added. As the emulsifying dispersant and the polymerization initiator, all of the above emulsifying dispersant and the polymerization initiator can be used,
These can be used alone or in combination of two or more.

The vinyl chloride resin of the present invention is obtained by graft-copolymerizing vinyl chloride onto the acrylic copolymer latex obtained by the above method.

When the proportion of the acrylic copolymer latex in the vinyl chloride resin is small, it becomes difficult to obtain sufficient impact resistance, and when the proportion is large, the mechanical strength such as tensile strength becomes low. -30% by weight, preferably 4-22% by weight.

If the proportion of vinyl chloride in the vinyl chloride resin is small, it becomes difficult to obtain mechanical strength such as tensile strength, and if it is large, it becomes difficult to obtain sufficient impact resistance. It is 70 to 99% by weight, preferably 78 to 96% by weight in the vinyl resin.

Examples of the method for graft-copolymerizing vinyl chloride include an emulsion polymerization method and a suspension polymerization method. However, since the vinyl chloride resin obtained by the emulsion polymerization method has a problem of poor thermal stability. Suspension polymerization is preferred.

In the above suspension polymerization method, a dispersant and an oil-soluble polymerization initiator are used. However, since radical polymerization is advantageous in graft copolymerization, an oil-soluble polymerization initiator that generates radicals is preferably used. .

The above dispersant is added for the purpose of improving the dispersion stability of the above acrylic copolymer latex and efficiently carrying out the graft copolymerization of vinyl chloride. For example, methyl cellulose, ethyl cellulose, hydroxypropyl methyl cellulose, polyvinyl are added. Examples thereof include alcohols and partially saponified products thereof, gelatin, polyvinylpyrrolidone, starch, and maleic anhydride-styrene copolymers, and these can be used alone or in combination of two or more.

Examples of the oil-soluble polymerization initiator include:
Organic peroxides such as lauroyl peroxide, t-butyl peroxypivalate, diisopropyl peroxy dicarbonate, dioctyl peroxy dicarbonate, t-butyl peroxy neodecanoate and α-cumyl peroxy neodecanoate, Examples thereof include azo compounds such as 2,2-azobisisobutyronitrile and 2,2-azobis-2,4-dimethylvaleronitrile.

Further, in the above suspension polymerization method, a pH adjusting agent, an antioxidant and the like may be appropriately added if necessary.

As a specific example of the suspension polymerization method, for example, a reaction vessel equipped with a stirrer and a jacket, pure water,
Oil-soluble polymerization initiator, the acrylic graft copolymer,
Dispersing agent, if necessary adding a polymerization degree adjusting agent, then,
A method in which air in the polymerization vessel is discharged by a vacuum pump, vinyl chloride and, if necessary, other vinyl monomers are added under stirring conditions, and then the reaction vessel is heated by a jacket to perform graft copolymerization can be mentioned. . Further, since the above graft copolymerization is an exothermic reaction, it is possible to control the temperature in the reaction vessel by changing the jacket temperature. After the completion of the reaction, unreacted vinyl chloride is removed to obtain a slurry, which is further dehydrated and dried to produce a vinyl chloride resin.

When the degree of polymerization of polyvinyl chloride in the above vinyl chloride resin is small, it becomes difficult to obtain sufficient elongation at break and impact resistance of the molded product, and when it is large, the fluidity is lowered and sufficient moldability is obtained. Is less likely to be obtained, it is preferably 300 to 2000, and more preferably 400 to 1400.
Is.

To the vinyl chloride resin of the present invention, a heat stabilizer, a stabilizing aid, a lubricant, a processing aid, an antioxidant, a light stabilizer, a filler, a pigment and the like are added as required during molding. Used.

Examples of the heat stabilizer include dimethyltin mercapto, dibutyltin mercapto, dioctyltin mercapto, dibutyltin malate, dibutyltin malate polymer, dioctyltin malate, dioctyltin malate polymer, dibutyltin laurate, dibutyltin. Organotin stabilizers such as laurate polymers, lead stearate, dibasic lead phosphite, lead stabilizers such as tribasic lead sulfate, calcium-zinc stabilizers, barium-zinc stabilizers, barium -Cadmium stabilizers and the like.

Examples of the stabilizing aid include epoxidized soybean oil, epoxidized linseed oil, epoxidized tetrahydrophthalate, epoxidized polybutadiene, and phosphoric acid ester.

Examples of the lubricant include montanic acid wax, paraffin wax, polyethylene wax,
Examples thereof include stearic acid, stearyl alcohol, butyl stearate and the like.

Examples of the processing aid include acrylic processing aids which are alkyl acrylate / alkyl methacrylate copolymers having a weight average molecular weight of 100,000 to 2,000,000, and specific examples include n-butyl acrylate / Examples thereof include methyl methacrylate copolymer and 2-ethylhexyl acrylate / methyl methacrylate / butyl methacrylate copolymer.

Examples of the above antioxidant include phenolic antioxidants and the like.

Examples of the light stabilizers include salicylic acid ester-based, benzophenone-based, benzotriazole-based, cyanoacrylate-based ultraviolet absorbers, hindered amine-based light stabilizers, and the like.

Examples of the filler include calcium carbonate, talc and the like.

Examples of the above-mentioned pigments include azo-based, phthalocyanine-based, slene-based, dye lake-based, etc. organic pigment oxides, oxides, chromate molybdic acid-based, sulfide / selenide-based, ferrocyanide-based pigments. Inorganic pigments such as

A plasticizer may be added to the vinyl chloride resin for the purpose of improving processability during molding.
For example, dibutyl phthalate, di-2-ethylhexyl phthalate, di-2-ethylhexyl adipate and the like can be mentioned.

The method of mixing the above additives with the vinyl chloride resin may be either a hot blending method or a cold blending method, and the molding method may be, for example, an extrusion molding method, an injection molding method or a calender. A molding method, a press molding method and the like can be mentioned.

[0046]

Embodiments of the present invention will be described below.
In the following, "parts" means "parts by weight".

Examples 1 to 11 and Comparative Examples 1 to 8 Vinyl chloride resins were obtained in accordance with the compounding compositions shown in Tables 1 and 2 by the following operating procedure. (Preparation of acrylic copolymer) Pure water and anionic surfactant (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., trade name "Monogen Y-100") were placed in a reaction vessel equipped with a stirrer and a reflux condenser.
(Hereinafter referred to as AS), ammonium persulfate (hereinafter referred to as A
PS), n-butyl acrylate (hereinafter, BA), methyl methacrylate (hereinafter, MMA), trimethylolpropane triacrylate (hereinafter, TMPTA) are charged, and oxygen in the container is replaced with nitrogen. After that, the reaction vessel was heated to 65 ° C. under stirring conditions and heated and stirred for 5 hours to obtain an acrylic copolymer (hereinafter referred to as a copolymer).

(Preparation of Acrylic Copolymer Latex)
Then, in a reaction vessel containing the above copolymer, MM
A and TMPTA were added, and oxygen in the container was replaced with nitrogen in the same manner as above, and then the reaction container was cooled to 65% under stirring conditions.
The temperature was raised to 0 ° C., and the mixture was heated and stirred for 2 hours to obtain an acrylic copolymer latex (hereinafter referred to as latex) having a solid content concentration of 31% by weight.

(Preparation of Vinyl Chloride Resin) Next,
In a reaction vessel equipped with a stirrer and jacket, obtain the above
Latex, pure water, partially saponified polyvinyl alcohol
Le (manufactured by Kuraray Co., Ltd., trade name "Clam Poval L-
8 ") 3% aqueous solution (hereinafter referred to as 3% PVAaq),
t-Butylperoxy neodecanoate (hereinafter referred to as BPO
ND) and α-cumylperoxy neodecanoe
(Hereinafter, referred to as QPOND) were put in at one time. That
After that, the air inside the polymerization vessel was discharged with a vacuum pump, and the stirring line
Stir for 30 minutes after adding vinyl chloride under the conditions
To uniformly mix vinyl chloride, raise the temperature to 57 ° C and
It started to work. 5 hours after the start of polymerization, the pressure in the reaction vessel
Power is 7 kg / cm ²After confirming that the
I stopped. After the reaction was completed, unreacted vinyl chloride was removed.
Then, it was dehydrated and dried to obtain a vinyl chloride resin.

(Preparation of vinyl chloride resin test panel) For 100 parts of the vinyl chloride resin obtained above,
3 parts of dioctyl tin mercapto (manufactured by Sansha Kisei Co., Ltd., trade name "ONZ-142F"), montanic acid wax (manufactured by Hoechst Japan Co., Ltd., trade name "WAX-O"
P ") 0.5 part, and the mixture was kneaded with a roll kneader at 190 ° C for 3 minutes, and then the temperature was 195 ° C and the pressure was 75 k.
Press molding was performed at g / cm ² for 6 minutes to obtain a vinyl chloride resin test panel having a thickness of 3 mm.

Evaluation items and evaluation methods are shown below. (Impact resistance) The results of an Izod impact test (hereinafter referred to as Izod) based on JIS K7110 are shown in Table 1. The unit is kg · cm / cm ² . (Tensile Strength) Table 1 shows the results of a tensile strength test conducted in accordance with JIS K7113. The unit is kg / cm ² .

[0052]

[Table 1]

[0053]

[Table 2]

[0054]

The vinyl chloride resin of the present invention is a vinyl chloride resin having excellent impact resistance and mechanical strength because it is graft-copolymerized with vinyl chloride on an acrylic copolymer latex. It can be suitably used for applications requiring impact resistance such as soundproof walls, window frames and sashes.

Claims (1)

[Claims] 1. A vinyl chloride resin obtained by graft-copolymerizing 1 to 30% by weight of acrylic copolymer latex with 70 to 99% by weight of vinyl chloride, wherein the acrylic copolymer latex is A) Acrylic copolymer containing 1 to 50% by weight of a mixed monomer consisting of 100 parts by weight of a vinyl monomer having a glass transition temperature of -20 ° C. or higher and (B) 0.1 to 20 parts by weight of a polyfunctional monomer. 5
The acrylic copolymer is obtained by graft copolymerization in an amount of 0 to 99% by weight, and the acrylic copolymer contains an alkyl (meth) acrylate whose homopolymer (C) has a glass transition temperature of less than -20 ° C as a main component. A vinyl chloride resin characterized by being obtained by copolymerizing 100 parts by weight of an acrylic monomer and 0.1 to 10 parts by weight of a polyfunctional monomer (B).