JPS6357658A - Production of vinyl chloride resin composition - Google Patents

Abstract

PURPOSE:To obtain the title compsn. which is uniform contains no agglomerates and gives molded products having an excellent appearance, by blending a vinyl chloride resin with a plasticizer-impregnated acrylic resin powder. CONSTITUTION:100pts.wt acrylic resin powder (a) having a particle size of not larger than 600mu and an MW of 300,000-2,500,000, such as a (co)polymer of an acrylic ester of the formula (wherein R is H or a lower alkyl; and R<1> is a 1-18C alkyl) is impregnated with 10-100pts.wt. plasticizer (b) (e.g., di-2- ethylhexyl phthalate) at 100 deg.C or lower to obtain a plasticizer-impregnated acrylic resin powder (B) having a particle size of not larger than 500mu. 100pts.wt. vinyl chloride resin (A) (e.g., vinyl chloride homopolymer) is blended with the components B and (b) in such an amount that the component (a) is 0.1-10pts.wt. and the component (b) is 30-400pts.wt.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application J] The present invention relates to a method for producing a vinyl chloride resin composition. More specifically, the present invention relates to a vinyl chloride resin composition that prevents the formation of spots caused by unmelted particles of acrylic resin in the vinyl chloride resin composition and has a good surface appearance.

"Prior Art" Many extrusion molded products made from vinyl chloride resin compositions are known. Vinyl chloride resin compositions to which a small amount of acrylic resin such as polymethyl methacrylate is added as a molding aid for the purpose of facilitating extrusion molding are often used.

However, although simply adding and mixing an acrylic resin to a vinyl chloride resin has the effect of improving extrusion, in the melting process of resin i acid, the melt viscosity of the acrylic resin is higher than that of the vinyl chloride resin. Because the acrylic resin is large and large, the acrylic resin is not sufficiently melted and dispersed, and when extrusion molding is performed using such a composition, unmelted acrylic resin, so-called "putu", appears on the surface of the molded product. Irregularities caused by the particles were formed, and the surface appearance of the molded product was seriously impaired, making it unsatisfactory for practical use.

``Problems to be Solved by the Present Invention'' Under such circumstances, the inventors of the present invention have conducted intensive studies on a method for producing molded products made of vinyl chloride resin that has no lumps and has a good surface appearance. Rather than simply tri-blending the resin and plasticizer, acrylic resin powder pre-impregnated with plasticizer is mixed with vinyl chloride P.
The present invention was completed based on the discovery that by using a composition blended with a resin, a molded product with a good surface appearance without lumps can be produced without deteriorating extrusion moldability.

That is, an object of the present invention is to provide a method for producing a vinyl chloride resin composition that eliminates spots that appear on the surface of a molded product when an acrylic resin is added to the vinyl chloride resin composition.

"Structure of the Invention" The gist of the present invention is to mix an acrylic resin powder impregnated with a plasticizer with a vinyl chloride resin in a method for producing a vinyl chloride resin composition containing an acrylic resin. A method for producing a vinyl chloride resin composition is provided.

The present invention will be described in detail.

The acrylic resin to be contained in the vinyl chloride resin composition is not particularly limited. Usually, a polymer whose main component is an acrylic acid monomer such as acrylic acid, methacrylic acid, or an ester thereof is used. The comonomer copolymerized with the acrylic acid monomer may be a polymer or a copolymer. Among various acrylic acid monomers, the following general formula IIICH, =CR-
COOR'...[I] [Wherein, R represents a hydrogen atom or a lower alkyl group, and R' represents an alkyl group having from a1 to 18 carbon atoms. ] Preferred are acrylic esters represented by the following, specifically, for example, methyl acrylate, ethyl acrylate, -0-propyl acrylate, -;-propyl acrylate, a-n-butyl acrylate, and -1-acrylate. -Butyl, 2-ethylhexyl acrylate, n-octyl acrylate, dodecyl acrylate, hexadecyl acrylate, octadecyl acrylate, methyl methacrylate, ethyl methacrylate, propyl tutaacrylate, n-butyl methacrylate, methacrylic acid Examples include, but are not limited to, -1-butyl, hexyl methacrylate, -0-octyl methacrylate, -2-ethylhexyl methacrylate, decyl methacrylate, cyclohexyl methacrylate, and octadecyl methacrylate.

In addition, comonomers other than acrylic acid monomers that can be copolymerized with these acrylic acid group esters include 7-crylonitrile, metacyclonitrile, vinyl acetate, vinyl propionate, vinyl laurate, diptyl maleate,
Examples include diethyl maleate, diethyl hexamalate, diptyl fumarate, vinyl methyl ether, vinyl butyl ether, butanoene, styrene, etc., and these do not impair various physical properties such as extrusion performance and thermal stability of the vinyl chloride resin composition. Copolymerized into acrylic resin within a range.

Typical acrylic resins include, for example, polymethyl acrylate, polymethyl methacrylate, and methyl methacrylate-butano-ene-styrene copolymer (MBS). The molecular weight of these acrylic resins is 3
A particle size in the range of 0,000 to 2,500,000 is generally used, and the particle size is preferably 600 μm or less.

In the method of the present invention, the plasticizer to be impregnated into the acrylic resin is not particularly limited as long as it is commonly used as a plasticizer for vinyl chloride resins.

For example, di-n-butyl 7-talate, 2-octyl 7-talate, di-2-ethylhexyl 7-talate, noisooctyl 7-talate, octyldecyl 7-talate, diindecyl 7-talate, butylbennol 7-talate, no-2 isophthalate. - 7-talic acid plasticizers such as ethylhexyl or higher alcoholic acid esters having about 11 to 13 carbon atoms, 1-octyl-〇-decyl trinoliftate, tri-2-ethylhexyl trimellitate, triisodecyl trimellitate, Trimellitic acid plasticizers such as tri-octyl trimellitate, di-2-ethylhexyl 7-dibate, di-n-decyl 7-nopinate, diisodecyl adipate, di-2-ethylhexyl azelaate, diptyl sepacate, no sebacate Fatty acid ester plasticizers such as 2-ethylhexyl, tributyl phosphate, tri-2-ethylhexyl phosphate, 2-ethylhexyldiphenyl phosphate, phosphate ester plasticizers such as tricresyl phosphate, 7-divic acid and ethylene glycol Polyester obtained by esterifying the terminal carboxylic acid group of a polycondensate with 2-ethylhexanol, polyester obtained by esterifying the terminal carboxylic acid group of a polycondensate of adipic acid and propylene glycol with 2-ethylhexanol, Novinic acid and 1
, polyester obtained by esterifying the terminal carboxylic acid group of a polycondensate with 3-butanediol with 2-ethylhexanol, and esterifying the terminal carboxylic acid group of a polycondensate of azelaic acid with ethylene glycol with 2-ethylhexanol. Polyester, a polyester in which the terminal carboxylic acid group of a polycondensate of azelaic acid and 1,3-butanediol is esterified with 2-ethylhexanol, and a polyester in which the terminal carboxylic acid group of a polycondensate of 7-talic acid and ethylene glycol is - Polyester esterified with ethylhexanol, polyester esterified with lauric acid at the terminal hydroxyl group of a polycondensate of adipic acid and ethylene glycol, lauric acid at the terminal hydroxyl group of a polycondensate of adipic acid and 1,3-butanediol Examples include polymeric plasticizers such as acid-esterified polyester, epoxidized soybean oil, epoxidized 7-seed oil, epoxidized tall oil fatty acid-2-ethylhexyl, and epoxy plasticizers such as liquid epoxy resin. In the method of the present invention, in which one type or a mixture of 211 or more of these is used, a 7-talic acid plasticizer is generally used from an economic point of view, but in order to maintain the performance required for a vinyl chloride resin composition. In addition, trimellitic acid plasticizers, fatty acid ester plasticizers, phosphate ester plasticizers, and polymeric plasticizers may be used alone or in combination. Epoxy plasticizers are usually used in combination with other plasticizers for the purpose of improving thermal stability.

As the vinyl chloride resin used in the method of the present invention, vinyl chloride or a mixture of vinyl chloride and a copolymerizable copolymerizable resin is commonly used by suspension polymerization, bulk polymerization, fine suspension polymerization, or emulsion polymerization. All products manufactured by this method can be used.

Therefore, examples of comonomers that can be copolymerized with vinyl chloride include vinyl esters such as vinyl acetate, vinyl propionate, and vinyl laurate; methyl acrylate;
Acrylic acid esters such as ethyl acrylate and butyl acrylate, methacrylic acid esters such as methyl methacrylate and ethyltutaacrylate, maleic acid esters such as dibutyl maleate and butyl 7-maleate, butyl 7-maleate, butyl 7-maleate, etc. 77-ruic acid esters, vinyl ethers such as vinyl methyl ether, vinyl butyl ether, and vinyl octyl ether, vinyl cyanides such as acrylonitrile and metacyclonitrile, a-olefins such as ethylene, propylene, and styrene, vinylidene chloride, Examples include 7% vinylidene lodenide or vinyl halides other than vinyl chloride such as vinyl bromide, and these comonomers are used in an amount of 30% by weight or less, preferably 20% by weight or less in the constituent components of the vinyl chloride resin. It will be done. Of course, the como/mar is not limited to those mentioned above.

In addition to the above-mentioned plasticizer, the vinyl chloride resin may contain, if necessary, known resin additives that are usually added to synthetic resins for molding, such as heat stabilizers, antioxidants, lubricants, and surfactants. Agents, ultraviolet absorbers, light stabilizers, pigments, dyes, etc. may be added.

The method of the present invention involves impregnating an acrylic resin with a plasticizer and mixing it with a vinyl chloride resin to produce a vinyl chloride resin composition.

In order to impregnate the acrylic resin with the plasticizer, the plasticizer is impregnated at a ratio of 10 to 100 parts by weight, preferably 200 parts by weight to 50 parts by weight or less, per 100 parts by weight of the acrylic resin, and the temperature is preferably 100° C. or less. It is preferable to impregnate the acrylic resin at a temperature of 40° C. or lower. If the amount of plasticizer is more than 100 parts by weight, the viscosity of the acrylic resin will be lowered, but the particles will be more likely to block, making handling difficult. If the amount is less than 10 parts by weight, the viscosity of the acrylic M resin will not decrease, causing spots to be formed on the surface of the molded product.

It is desirable to change the amount of plasticizer depending on the melt viscosity of the vinyl chloride resin composition, and if the impregnation temperature is 100°C or higher, the acrylic resin will block and the mixing tank (
The size of the particles of the acrylic resin powder impregnated with a plasticizer is preferably 500μ or less, preferably 50μ or more and 400μ or less, which is undesirable because it causes sticking.Also, to obtain the acrylic U4 fat powder, use a water-cooled mixer. Place the acrylic resin in the container and add the required amount of plasticizer while stirring. Stir for a while further to dry up.

Therefore, the amount of plasticizer contained in a vinyl chloride resin composition varies depending on the moldability, processability, workability of the composition, the use of the molded product, etc., but in general, the amount of plasticizer contained in the vinyl chloride resin composition is based on 100 parts by weight of the vinyl chloride resin. 30-400 parts by weight, preferably 50-2
00 parts by weight. On the other hand, the amount of acrylic resin contained in the composition is 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, particularly 0.5 to 3 parts by weight, based on 100 parts by weight of vinyl chloride resin. This is within the scope of the department.

The vinyl chloride resin composition produced by the method of the present invention can be produced simply by uniformly blending the above-mentioned essential components and other additives as necessary using a mixing agitator such as a super mixer, ribbon mixer, change can mixer, etc. be adjusted. The composition is used as it is for extrusion molding of tubes and the like. Furthermore, specifically, for example, a vinyl chloride resin composition is produced from a vinyl chloride polymer obtained by suspension polymerization or bulk polymerization! ! To serve, the vinyl chloride resin, the plasticizer in which the acrylic resin is dissolved, and other additives as necessary are uniformly mixed in a super mixer, ribbon mixer, etc., and dried up. Furthermore, if necessary, the composition may be heated and melted in a kneading machine such as a roll, a Banbury mixer, or an extruder, then formed into a sheet or strand, and then formed into a pellet-like composition using a sheet cutter or pelletizer. The resin composition is generally made into a molded article by extrusion molding or blow molding. In addition, in order to produce a vinyl chloride resin composition from a vinyl chloride resin obtained by emulsion polymerization or fine suspension polymerization, a vinyl chloride resin, an acrylic resin impregnated with a plasticizer, and other additives as necessary are required. A plastisol composition is prepared by uniformly mixing the ingredients using a mixing agitator such as a super mixer or a Niichig.

The sol composition is made into a molded article by a rotational molding method, a slush molding method, or the like.

"Effects of the Invention" Since the vinyl chloride resin composition produced by the method of the present invention contains acrylic resin uniformly in the composition without lumps, 91 molded products can be produced from the composition. In this case, no bumps caused by the acrylic resin are observed on the surface of the molded product, and a molded product with a good surface appearance can be obtained.

"Examples" Next, the method of the present invention will be explained in detail with reference to Examples, but the present invention is not limited to the following Examples unless the gist thereof is exceeded.

Vinyl chloride PS resin 100 parts by weight (average degree of polymerization p 1300.PVC) 7 Di-2-ethylhexyl talate 60 parts by weight (DOP) Polymethyl methacrylate 2 parts by weight (molecular weight approximately 600,000, PMMA) Tribasic lead sulfate 2 Part by weight Lead stearate 0.5 part by weight A vinyl chloride resin composition having the above-mentioned mixing ratio was produced as follows.

(1) 100 parts by weight of PMMA powder is stirred in a Henschel mixer while cooling the mixing tank with water, and parts by weight of DOPIO are added.The mixture is further stirred for 5 minutes to form a powder impregnated with DOP. Two parts by weight of PMMA impregnated with this DOP were mixed with other compounding agents in a Henschel mixer to prepare a vinyl chloride resin composition.

(2) 100 parts by weight of PMMA powder is stirred in a Henschel mixer while cooling the mixing tank with water, and 20 parts by weight of DOP is added. Stir for an additional 5 minutes to form a powder impregnated with DOP. Two parts by weight of PMMA impregnated with this DOP were mixed with other compounding agents in a Henschel mixer to prepare a vinyl chloride resin composition.

For comparison, polymethyl methacrylate not impregnated with a plasticizer was mixed with other ingredients in a Henschel mixer to prepare a vinyl chloride resin composition.

The vinyl chloride resin composition obtained by the above method was mixed at 175° C. using a Brabender type plastograph, and the deltized resin was pressed to form a thin film, and the presence or absence of unmelted particles of polymethyl methacrylate was examined.

The results are shown in Table 1.

In addition, when we measured the flow rate of vinyl chloride 0 (fatty acid) containing polymethyl methacrylate impregnated with a plasticizer using a flow tester, we found that the flow rate change was almost the same as that of a vinyl chloride resin composition that does not contain acrylic resin. Since the vinyl chloride resin composition obtained by the present invention has a value of .

Claims (3)

[Claims] (1) A method for producing a vinyl chloride resin composition containing an acrylic resin, which comprises mixing an acrylic resin powder impregnated with a plasticizer with a vinyl chloride resin. Production method. (2) Acrylic resin has the general formula CH_2=CR-COOR^1...[I][
In the formula, R represents a hydrogen atom or a lower alkyl group, and R^1 represents an alkyl group having 1 to 18 carbon atoms. ] The method for producing a vinyl chloride resin composition according to claim 1, which is a polymer or copolymer of an acrylic ester represented by the following. (3) The method for producing a vinyl chloride resin composition according to claim 1, wherein the amount of plasticizer impregnated into the acrylic resin is 10 to 100 parts by weight per 100 parts by weight of the acrylic resin.