JPH07216168A - Preparation of vinyl chloride resin composition - Google Patents

Abstract

PURPOSE:To prepare a vinyl chloride resin composition improved in heat resistance by previously dissolving an antioxidant in a plasticizer and adding the solution to a vinyl chloride resin. CONSTITUTION:As the vinyl chloride resin used, one produced by a suspension polymerization process or a bulk polymerization process and having an average degree of polymerization of 700-10000 is desirable. The antioxidant is used in an amount of 0.1-5 pts.wt. per 100 pts.wt. resin and is used in the form of a solution prepared by previously dissolving in a plasticizer. It is preferable that the antioxidant used is a phenolic antioxidant, a sulfur antioxidant or a phosphorus antioxidant and has a molecular weight of 500 or above and a melting point of 40 deg.C or above. The dissolution of the antioxidant in the plasticizer is carried out with slow agitation at 200 deg.C or below. Although the plasticizer is not particularly limited, it is suitably has a molecular weight of 400 or above. When oil resistance in addition to heat resistance is necessary, a polyester plasticizer is used. When heat resistance, thermal aging resistance and oil resistance are further to be improved, an alkyl biphenyltetracarboxylate is suitably used. The amount of the plasticizer used is 10-200 pts.wt. per 100 pts.wt. resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a vinyl chloride resin composition having improved heat resistance, which is suitable for use as an electric wire coating material.

[0002]

2. Description of the Related Art As electric appliances, automobile parts, etc. are becoming more compact and lighter, the coated electric wires used in the equipment, automobile engine room, etc. are becoming finer, and further heat resistance is required. Has arrived. Conventionally, an antioxidant is added for the purpose of improving the heat resistance of the vinyl chloride resin at high temperatures, but the antioxidant is used in a relatively small amount and the vinyl chloride resin is dried. When blending, it is simply mixed with additives other than plasticizers, for example, fillers, powders such as pigments, etc., and it is difficult to uniformly disperse the antioxidant in the vinyl chloride resin, and therefore heat resistance There was a problem that the improvement effect was difficult to be exhibited.

[0003]

The present inventors have studied various antioxidants for the purpose of improving the heat resistance of vinyl chloride resin compositions at high temperatures. Dissolving the oxidizer in the plasticizer and then blending it into the vinyl chloride resin makes it possible to achieve microdispersion even in the pores of the vinyl chloride resin, and to improve the uniform dispersibility, rather than mixing the antioxidant as it is. Then, they have found that the heat resistance of the vinyl chloride resin composition can be further improved, and have completed the present invention. That is, an object of the present invention is to provide a process for producing a vinyl chloride resin composition having improved heat resistance at high temperatures.

[0004]

The gist of the present invention is to provide a method for producing a vinyl chloride resin composition containing a plasticizer and an antioxidant, after the antioxidant is previously dissolved in the plasticizer. A method for producing a vinyl chloride resin composition is characterized in that it is added to and mixed with a vinyl chloride resin.
The present invention will be described in detail below.

The vinyl chloride resin used in the method for producing the composition of the present invention is a suspension polymerization method, a bulk polymerization method, a fine suspension polymerization method or an emulsion method in which vinyl chloride or a mixture of vinyl chloride and a comonomer copolymerizable therewith is used. All of those produced by a conventional method such as a polymerization method can be used, but the vinyl chloride resin produced by a suspension polymerization method or a bulk polymerization method is particularly effective. And the average degree of polymerization is 700
It is preferably in the range of 1 to 10,000, preferably 800 to 9000, and particularly preferably 1100 to 6000.

Examples of the comonomer copolymerizable with vinyl chloride include vinyl esters such as vinyl acetate, vinyl propionate and vinyl laurate, acrylic acid esters such as methyl acrylate, ethyl acrylate and butyl acrylate, and methyl ester. Methacrylates such as methacrylate and ethyl methacrylate, maleates such as dibutyl maleate and diethyl maleate, fumarates such as dibutyl fumarate and diethyl fumarate, vinyl methyl ether, vinyl butyl ether, vinyl octyl ether, etc. Vinyl ethers, acrylonitrile, methacrylonitrile and other vinyl cyanides, ethylene, propylene, styrene and other α-olefins, vinylidene chloride, vinyl bromide and other vinyl chloride Vinylidene halides or vinyl halides. These comonomers are, 30 wt% in the constituents of the vinyl chloride resin or less, preferably 2
It is used in the range of 0% by weight or less. Of course, the comonomers are not limited to those mentioned above.

The plasticizer used in the method for producing the vinyl chloride resin composition of the present invention is not particularly limited.
Di-n-butyl phthalate, di-n-octyl phthalate,
Such as di-2-ethylhexyl phthalate, diisooctyl phthalate, octyldecyl phthalate, diisodecyl phthalate, butylbenzyl phthalate, 2-ethylhexyl isophthalate, or phthalate esters of higher alcohols having about 11 to 13 carbon atoms. Phthalic acid plasticizers, trimellitic acid-n-octyl-n-decyl, trimellitic acid tri-2-ethylhexyl, tri-2-ethylhexyl triisodecyl, trimellitic acid tri-n-octyl, and other trimellitic acid plasticizers Agent, adipic acid di-2-
Fatty acid ester plasticizers such as ethylhexyl, di-n-decyl adipate, diisodecyl adipate, di-2-ethylhexyl azelate, dibutyl sebacate, di-2-ethylhexyl sebacate, tributyl phosphate, tri-2 phosphate -Phosphate ester plasticizers such as ethylhexyl, 2-ethylhexyl diphenyl phosphate, tricresyl phosphate, epoxidized soybean oil, epoxidized linseed oil, epoxidized tall oil fatty acid-2-ethylhexyl epoxy plasticizers or liquid Epoxy resin, etc.

When oil resistance is required in addition to heat aging resistance, it is preferable to use a polyester plasticizer. As the polyester-based plasticizer, any conventionally known polyester-based plasticizer (also called a polymer) can be used. That is, polycarboxylic acids such as succinic acid, adipic acid, azelaic acid, sebacic acid, phthalic acid and trimellitic acid, and ethylene glycol,
Polyhydric compounds such as 1,2-propylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, 1,5-pentanediol, 1,6-hexanediol and neopentyl glycol Polycondensate with alcohol (for example, average molecular weight 300 to 8)
000) is a monovalent alcohol such as butanol, pentanol, hexanol, heptanol, n-octanol, 2-ethylhexanol, nonanol, decanol, undecanol, dodecanol, tridecanol or the like, or a monovalent carvone. Acids such as acetic acid, propanoic acid, butanoic acid, 2-methylpropanoic acid,
Pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid, heptadecanoic acid, octadecanoic acid, cyclohexanoic acid, benzoic acid, etc. It is blocked with one or two or more species.

Further, for the purpose of improving heat resistance, heat aging resistance and oil resistance, it is desirable to use an alkyl biphenyltetracarboxylic acid ester as a plasticizer. Specific examples of such biphenyl tetracarboxylic acid alkyl ester include 2,3,3 ′, 4′- or 3,4.
3 ', 4'-biphenyltetracarboxylic acid tetrabutyl ester, 2,3,3', 4'- or 3,4,3 ',
4'-biphenyltetracarboxylic acid tetrapentyl ester, 2,3,3 ', 4'- or 3,4,3', 4 '
-Biphenyl tetracarboxylic acid tetrahexyl ester, 2,3,3 ', 4'- or 3,4,3', 4'-
Biphenyl tetracarboxylic acid tetraheptyl ester,
2.3.3 ', 4'- or 3,4,3', 4'-biphenyltetracarboxylic acid tetra (2-methylhexyl)
Ester, 2.3.3 ', 4'- or 3,4,3',
4'-biphenyltetracarboxylic acid tetra (n-octyl) ester, 2.3.3 ', 4'- or 3,4
3 ', 4'-biphenyltetracarboxylic acid tetra (2-
Ethylhexyl) ester, 2,3,3 ', 4'- or 3,4,3', 4'-biphenyltetracarboxylic acid tetraisooctyl ester, 2,3,3 ', 4'- or 3,4,3 ', 4'-biphenyltetracarboxylic acid tetranonyl ester, 2.3,3', 4'- or 3,
4,3 ', 4'-biphenyltetracarboxylic acid tetradecyl ester, 2.3.3', 4'- or 3,4
3 ', 4'-biphenyltetracarboxylic acid tetraundecyl ester, 2,3,3'. 4'- or 3,4
3 ', 4'-biphenyltetracarboxylic acid tetradodecyl ester, 2.3.3', 4'- or 3,4
3 ', 4'-biphenyl tetracarboxylic acid tetra (mixed oxo alcohol) ester etc. are mentioned.

When the composition obtained by the method of the present invention is used for use in a high temperature environment, or when the composition is used as an electric wire coating material, a low volatility having a molecular weight of 400 or more is selected from the above plasticizers. It is desirable to select and use one. As this plasticizer, a trimellitic acid plasticizer, a polyester plasticizer, and a biphenyltetracarboxylic acid alkyl ester plasticizer are particularly preferable.

The above plasticizers may be used alone or in combination of two or more. The amount of plasticizer used is
From the viewpoint of heat resistance, aging resistance and processability, 10 to 200 parts by weight, and especially 20 to 200 parts by weight are particularly preferable for 100 parts by weight of the vinyl chloride resin. The antioxidant used in the method of the present invention is not particularly limited as long as it is used for a vinyl chloride resin, and examples thereof include phenolic antioxidants, sulfur antioxidants, phosphorus antioxidants, amine antioxidants. Can be mentioned.

As the phenolic antioxidant, 2,6-
Di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, stearyl-β- (3,5-di-t-butyl-
Monophenolic antioxidants such as 4-hydroxyphenyl) propionate, 2,2-bis (4'-hydroxyphenyl) propane, 2,2'-methylene-bis- (4-
Methyl-6-t-butylphenol), 2,2′-methylene-bis- (4-ethyl-6-t-butylphenol), 4,4′-thiobis- (3-methyl-6-t-butylphenol), 4 , 4'-butylidene-bis- (3
-Methyl-6-t-butylphenol), 3,9-bis [1,1-dimethyl-2- [β- (3-t-butyl-4)
-Hydroxy-5-methylphenyl) propionyloxy] ethyl] 2,4,8,10-tetraoxaspiro [5,5] undecane and other bisphenol antioxidants,
1,1,3-tris- (2-methyl-4-hydroxy-
5-t-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-
4-hydroxybenzyl) benzene, tetrakis- [methylene-3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate] methane, bis [3,3'-bis (4'-hydroxy) -3'-t-butylphenyl) butyric acid] glycol ester, 1,3,5-tris (3 ', 5'-di-t-butyl-4'-hydroxybenzyl) -S-triazine-2,
There are polymeric phenolic antioxidants such as 4,6- (1H, 3H, 5H) trione, which all have a melting point of 4
It is a compound of 0 ° C or higher.

Examples of sulfur antioxidants include dilauryl thiodipropionate, dimyristyl thiodipropionate and distearyl thiopropionate. Also,
Examples of phosphorus antioxidants include triphenylphosphite, diphenylisodecylphosphite, phenyldiisodecylphosphite, 4,4′-butylidene-bis (3-methyl-6-t-butylphenyl-di-tridecyl) phosphite, Cyclic neopentane tetraylbis (octadecyl phosphite), tris (nonylphenyl) phosphite, tris (mono and / or dinonylphenyl) phosphite, diisodecyl pentaerythritol diphosphite, 9,10-dihydro-9-oxa -10-phosphaphenanthrene-10-oxide, 10-decyloxy-9,10-dihydro-9-oxa-10-phosphaphenanthrene, tris (2,4-
Di-t-butylphenyl) phosphite, cyclic neopentanetetraylbis (2,4-di-t-butylphenyl) phosphite, cyclic neopentanetetraylbis (2,6-di-t-butyl-) 4-methylphenyl) phosphite, 2,2-methylenebis (4,6
-Di-t-butylphenyl) octyl phosphite and the like, and many of them are liquid at room temperature.

Further, since the amine-based antioxidant tends to cause coloring during the molding and processing of the vinyl chloride-based resin, it is used in applications where coloring is not a problem. The method of the present invention is
Among the above-mentioned antioxidants, it is desirable to use one having a molecular weight of 500 or more, and it is preferable to use a phenolic antioxidant, particularly a high-molecular type phenolic antioxidant.
The method of the present invention can be effectively used as a method for uniformly dispersing an antioxidant having a melting point of 40 ° C. or higher at room temperature in a vinyl chloride resin composition.

However, the mixing ratio of the antioxidant is not particularly limited, but it is usually vinyl chloride resin 100.
It is in the range of 0.1 to 5 parts by weight per part by weight. If the compounding ratio of the antioxidant is less than 0.1 parts by weight, the effect of preventing heat deterioration of the vinyl chloride resin will be insufficient, while if it is too large, the effect of preventing heat deterioration in proportion to the compounding amount will be improved. It becomes economically disadvantageous. The method of the present invention consists in dissolving the above-mentioned antioxidant in a plasticizer in advance and then blending it with the vinyl chloride resin.

As the method for dissolving the antioxidant in the plasticizer, the most desirable method can be adopted depending on the blending amount of the plasticizer in the vinyl chloride resin and the required amount of the antioxidant. For example, the antioxidant is required. A method in which the amount of the antioxidant is dissolved in all plasticizers, the antioxidant is dissolved in a small amount of the plasticizer at a high concentration, and this plasticizer solution is added in the required amount of the antioxidant and the required amount of the plasticizer when preparing the vinyl chloride resin composition. There are various methods such as dilution. As a specific method of dissolving, for example, the plasticizer and the antioxidant are slowly stirred while heating, if necessary. The heating temperature depends on the type of plasticizer, antioxidant, etc., but 2
A temperature range of 00 ° C or lower, preferably 60 to 130 ° C is desirable. At temperatures higher than 200 ° C, the plasticizer is apt to volatilize or deteriorate. If the antioxidant is difficult to dissolve directly in the plasticizer, a good solvent for the antioxidant, for example, an organic solvent such as acetone, methanol, ethanol, chloroform, benzene, toluene, dioxane, cellosolve, or hexane is appropriately selected. You may employ | adopt the method of adding and stirring to a plasticizer, after melt | dissolving in the small amount.

For example, the above-mentioned tetrakis- [methylene-
3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate] methane (molecular weight 1178,
Melting point 120 ° C.) and stearyl-β- (3,5-di-t-
Butyl-4-hydroxyphenyl) propionate (molecular weight 530, melting point 49 to 52 ° C.) and other hindered phenolic antioxidants, 2,2-bis (4′-hydroxyphenyl) propane (bisphenol A, molecular weight 228, melting point 155) To 156 ° C.) are all plasticizers biphenyl tetracarboxylic acid tetraheptyl ester, trioctyl trimellitate, diisodecyl phthalate 10 each
It dissolves up to 30 parts by weight per 0 parts by weight.

In the method of the present invention, the plasticizer solution of the antioxidant thus prepared and the vinyl chloride resin are uniformly dispersed by, for example, a ribbon blender, a cake mixer, a grinder, a high speed mixer or the like. The composition. Further, this composition may be kneaded using a mill roll, a Banbury mixer, a pressure kneader, a single-screw kneading extruder, a twin-screw extruder, a plastifier, a cokneader or the like. The sheet or strand obtained by kneading may be cooled and then pelletized to obtain a pelletized composition.

In the method of the present invention, in addition to the above-mentioned essential components, additives usually used in vinyl chloride resins such as stabilizers, lubricants, flame retardants, ultraviolet absorbers, fillers, colorants, release agents. A mold agent is often used together. Moreover, you may add a chelator, a crosslinking agent, and a crosslinking aid as needed. As the lubricant, higher fatty acid or metal salt thereof, various paraffins, higher alcohols, natural waxes, polyethylene wax, fatty acid ester, fatty acid amide and the like are used. As the filler, calcium carbonate, clay, talc, fine silica powder, aluminum hydroxide or the like is used. As the flame retardant, antimony trioxide, barium borate, zinc borate, zinc oxide, chlorinated polyethylene and other halogen-based flame retardants are used.

The vinyl chloride resin composition produced by the method of the present invention is usually used as a coating material for a complex with an electrically conductive metal such as an electric wire. Examples of the electrically conductive metal include metals such as aluminum and copper, which may be subjected to surface treatment such as tin plating, and are usually strip-shaped or linear. Particularly, copper strips and linear strips are often used.

In order to compound the above vinyl chloride resin composition with these metals, for example, (1) a method of extrusion coating the composition on a strip-shaped or linear metal with an extruder, (2) a strip-shaped method A method of extrusion laminating the composition on one or both sides of the metal of the composition through an adhesive or directly with an extruder,
(3) First, the composition is formed into a film or sheet shape by a method such as extrusion or calendering, a strip-shaped or linear metal is arranged between the films or sheets, and then the laminated films or sheets are heat-welded to each other. Various methods such as the method of doing are adopted.

[0022]

According to the method of the present invention, since a relatively small amount of an antioxidant is dissolved in a plasticizer in advance and is blended in a vinyl chloride resin, the plasticizer and the antioxidant are separately prepared. A vinyl chloride resin composition having a good dispersibility of an antioxidant in a vinyl chloride resin and excellent heat resistance as compared with a compound blended with a vinyl chloride resin can be obtained. Therefore, the vinyl chloride resin composition produced by the method of the present invention,
It has a very high utility value as a thin-walled covering material for covered electric wires arranged in automobile engine rooms and for electric appliances.

[0023]

EXAMPLES Next, the method of the present invention will be described in detail with reference to Examples, but the present invention is not limited to the following Examples without departing from the gist thereof.

Examples 1 to 4, Comparative Examples 1 to 4 Tetrakis- [methylene-3- (3 ', 5'-di-t-butyl-4'-hydroxy] in the amounts (parts by weight) shown in Table-1. Phenyl) propionate] methane (antioxidant)
It was added to 60 parts by weight of biphenyl tetracarboxylic acid tetraheptyl ester (plasticizer) and stirred at 100 ° C. for 10 minutes. After confirming that the antioxidant was completely dissolved, the mixture was cooled to room temperature, and 100 parts by weight of a vinyl chloride resin having an average degree of polymerization of 1300 and 10 parts by weight of lead silicate produced by suspension polymerization of this plasticizer. And 1 part by weight of lead stearate (heat stabilizer) were put in a super mixer and blended, and dried up to prepare a vinyl chloride resin composition.

Further, a vinyl chloride resin composition was prepared in the same manner as in Example except that the same antioxidant powder as in Example was dried up without being dissolved in the plasticizer, and it was used as a comparative example. Each vinyl chloride resin composition obtained by the above method was kneaded with a 9-inch mill roll at 170 ° C. for 7 minutes to obtain a sheet having a thickness of about 0.3 mm. Next, several sheets of this sheet were stacked and press-molded at a temperature of 200 kg / cm ² between 180 ° C. hot plates via a mirror press plate to form a sheet having a thickness of 1 mm, from which a dumbbell-shaped test piece was prepared.
A heat aging test was performed on this test piece in accordance with JIS-K-6723, and the elongation residual ratio and the weight reduction ratio were 158 ° C. × 2.
The measurement was performed under the conditions of week and 158 ° C. × 4 weeks, and the results are shown in Table 1.

[0026]

[Table 1]

As shown in Table 1, in the heat aging test under the conditions of 158 ° C. × 2 weeks and 158 ° C. × 4 weeks, the compositions produced by the method of the present invention of Examples 1 to 4 were:
It can be seen that, as compared with the composition of Comparative Example to which the antioxidant is added in the same amount, each has a large elongation residual ratio and a small weight reduction ratio. That is, the composition prepared by the method of the present invention has improved heat resistance as compared with the composition prepared by the conventional method.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H01B 3/44 B 7/34 A

Claims (7)

[Claims] 1. A method for producing a vinyl chloride resin composition containing a plasticizer and an antioxidant, wherein the antioxidant is previously dissolved in the plasticizer and then added and mixed with the vinyl chloride resin. A method for producing a vinyl chloride resin composition. 2. The method for producing a vinyl chloride resin composition according to claim 1, wherein the antioxidant is a phenolic antioxidant, a sulfur antioxidant or a phosphorus antioxidant. 3. The method for producing a vinyl chloride resin composition according to claim 1, wherein the antioxidant has a molecular weight of 500 or more. 4. The method for producing a vinyl chloride resin composition according to claim 1, wherein the antioxidant has a melting point of 40 ° C. or higher. 5. The method for producing a vinyl chloride resin composition according to claim 1, wherein the plasticizer has a molecular weight of 400 or more. 6. The method for producing a vinyl chloride resin composition according to claim 1, wherein the antioxidant is dissolved in the plasticizer while slowly stirring in a temperature range of 200 ° C. or lower. . 7. A method for producing a vinyl chloride resin wire coating material by the method according to any one of claims 1 to 6.