JPS6261610B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a vinyl chloride resin composition from which molded articles with excellent solvent extraction resistance can be obtained. Soft vinyl chloride resin has traditionally been used for boots,
gloves, flooring, pipes, agricultural films, wall coverings,
Widely used for hoses, leather, etc. However, when boots, gloves, leather, etc. in particular come into contact with organic solvents, for example, when subjected to dry cleaning, the plasticizer of the molded product is extracted by the organic solvent, such as trichlorethylene, and dimensional changes may occur. There were disadvantages such as loss of flexibility, which limited the number of times it could be used repeatedly. Polyester plasticizers and trimellitic acid esters of higher alcohols are used to improve the solvent resistance of plasticizers, but ordinary vinyl chloride resins do not have a sufficient effect on solvent extraction resistance, and A high degree of solvent extraction resistance is required. As a result of extensive studies to meet such requirements, the inventors of the present invention have found that by using a special crosslinkable vinyl chloride copolymer and a polyester plasticizer or a trimellitic acid plasticizer, solvent extraction resistance can be improved. We have discovered that this can be dramatically improved and have arrived at the present invention. That is, an object of the present invention is to provide a vinyl chloride resin composition from which molded articles with excellent solvent extraction resistance can be obtained. Therefore, the gist of the present invention is a composition comprising a vinyl chloride resin, a crosslinking agent for the vinyl chloride resin, and a plasticizer, and the vinyl chloride resin has at least a portion of vinyl chloride, a hydroxyl group, a carboxyl group, Contains a vinyl chloride copolymer with a vinyl comonomer having an epoxy group or an alkoxy group,
The vinyl chloride resin composition is characterized in that at least a portion of the plasticizer contains a polyester plasticizer or a trimellitic acid plasticizer. The present invention will be explained in detail. The vinyl chloride resin used in the composition of the present invention is
A portion thereof contains a vinyl chloride copolymer (hereinafter referred to as a crosslinkable copolymer) having at least a crosslinkable group such as a hydroxyl group, a carboxyl group, an epoxy group, or an alkoxy group in the molecule. The crosslinkable copolymer can be obtained, for example, by a method of copolymerizing a vinyl chloride monomer and a comonomer having a hydroxyl group, a carboxyl group, an epoxy group, or an alkoxy group in the molecule, and specific examples of such a comonomer include: Examples include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, and 2-hydroxyethyl acrylate.
Hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl methacrylate, 3-
Hydroxybutyl acrylate, ethyl-2-hydroxyethyl fumarate, hydroxybutyl vinyl ether, glycidyl acrylate, glycidyl methacrylate, methacrylic acid, acrylic acid, itaconic acid, monobutyl maleate, undecylenic acid, N-methylolacrylamide, N-
Examples include butoxymethylacrylamide. Furthermore, the amount of the above-mentioned comonomer in the above-mentioned crosslinkable copolymer is not particularly limited, but it is preferably one containing 0.5 to 10% by weight of the above-mentioned comonomer, and the content of the comonomer is 0.5% by weight. If it is less than 10% by weight, the crosslinking density will be low and the effect of solvent extraction resistance will be small.If it is more than 10% by weight, the excellent physical properties of the vinyl chloride resin itself will not be expressed, and if it is made into plastisol, the storage stability will be poor. There is a tendency for this to be lacking.
In addition, this crosslinkable copolymer can be prepared by a known method, namely,
It may be obtained by any polymerization method such as suspension, emulsification, or lump form. However, in the present invention, those obtained by emulsion polymerization or fine suspension polymerization are most preferred from the viewpoints of particle size, meltability, crosslinkability, and sol preparation. The vinyl chloride resin composition of the present invention may contain, as a resin component, a non-crosslinkable vinyl chloride polymer that does not have crosslinking properties in addition to the above-mentioned crosslinkable copolymer, and specific examples thereof include: Vinyl chloride homopolymers, copolymers of vinyl chloride monomers and comonomers that do not have crosslinkable groups such as hydroxyl or carboxyl groups, for example, copolymers of vinyl chloride monomers and vinyl ethers, acrylic esters, olefins, etc. These are also suspension polymerization,
It may be obtained by any known method such as emulsion polymerization or bulk polymerization. However, for the purpose of preparing plastisols and organosols, those obtained by emulsion polymerization or fine suspension polymerization are desirable. The blending ratio of the crosslinkable copolymer and the non-crosslinkable vinyl chloride polymer in the vinyl chloride resin composition of the present invention is not particularly limited, but per 100 parts by weight of the total amount of both, The former is preferably blended in an amount of 10 parts by weight or more, preferably 20 parts by weight or more, particularly 50 parts by weight or more. When the vinyl chloride polymer used in the composition of the present invention is produced by emulsion polymerization or fine suspension polymerization, the particle size is approximately 0.1 to 5 μm, so pressure and shear force are not applied when melting the polymer particles. In addition, since the particle surface area per unit weight is large, the degree of mixing with the crosslinking agent is large, and the progress of the crosslinking reaction can proceed simultaneously with melting, resulting in uniform crosslinking. The crosslinking agent used in the vinyl chloride resin composition of the present invention has two functional groups in one molecule that can react with a vinyl chloride copolymer having a carboxyl group, an epoxy group, or an alkoxy group. It is a compound having more than one. Such crosslinking agents include, for example, compounds having an isocyanate group, carboxyl group, hydroxyl group, epoxy group, alkoxyalkylamino group, hydroxyalkylamino group, amino group, alkyl mono- or di-substituted amino group in the molecule, dibasic Examples include acid anhydrides, specifically tolylene diisocyanate,
Diphenylmethane diisocyanate, trimethylolpropane tolylene diisocyanate and its adducts, polymethylene polyphenyl isocyanate, succinic acid, glutaric acid, adipic acid, pimelic acid, azelaic acid, phthalic acid, phthalic anhydride, maleic acid, anhydride Cyclohexanedicarboxylic acid, triglycidyl isocyanurate, 4,4'-
Examples include diaminophenylmethane glycidylamine, bisphenol type epoxy, epoxy resin, triethylenetetramine, methylolmelamine, butoxymethylmelamine, and polyisocyanates blocked with alcohol, phenol, etc. can also be used. The amount of these crosslinking agents used varies depending on the type thereof, but is preferably 0.2 parts by weight or more, preferably 1 to 10 parts by weight, based on the content of the crosslinkable copolymer. The greater the amount of crosslinking agent, the greater the crosslink density. At least a portion of the plasticizer to be blended as a component of the vinyl chloride resin composition of the present invention must be a polyester plasticizer or a trimellitic acid plasticizer. Polyester plasticizers are generally ethylene glycol, 1,3-
Propanediol, 1,2-butanediol,
A polyhydric alcohol such as 1,3-butanediol, 1,4-butanediol, or 1,6-hexanediol is condensed with a polyhydric carboxylic acid such as phthalic acid, adipic acid, or trimellitic acid to form a monohydric alcohol or It is produced by terminal treatment with carboxylic acid. The performance of the polyester plasticizer is correlated with its degree of polymerization (average molecular weight), and the lower the degree of polymerization, the better the plasticization efficiency, cold resistance, processability, etc., but the lower the degree of polymerization, the better the plasticization efficiency, cold resistance, processability, etc. Performance such as migration properties deteriorates, while those with a high degree of polymerization have poor compatibility with synthetic resins compared to monomeric plasticizers such as dioctyl phthalate, leading to a decrease in plasticizing efficiency and processability. , the viscosity of the plasticizer increases and workability becomes poor. In the composition of the present invention, it is preferable to use a polyester plasticizer with excellent solvent extraction resistance, but the type thereof should be appropriately determined in consideration of the intended use of the composition of the present invention. If the processability is poor, it can be improved by adding an appropriate amount of a conventional monomeric plasticizer. Examples of commercially available polyester plasticizers include Plasticizer D409 (manufactured by Mitsubishi Monsanto Chemical Co., Ltd.), PN-250, and PN-650.
(manufactured by Adeka Argus Chemical), etc. Further, the trimellitic acid plasticizer is produced by an esterification reaction of trimellitic acid and alcohol. As the alcohol, alcohols having about 4 to 21 carbon atoms are usually used.
The alcohol may have a branched chain. For example, butanol, pentanol, hexanol, heptanol, 3-methylhexanol, 5-methylhexanol, 2,4-dimethylpentanol, octanol, 2-ethylhexanol, nonanol, indecanol, tridecanol, carbon obtained by cracking wax. Examples include alcohols having 4 to 21 atoms, and at least one of these is used. Number of carbon atoms: 4 to 13,
Particularly preferred are 6-13 higher alcohols. Among these, a trimellitic acid ester plasticizer, which is obtained by condensing 2-ethylhexanol or a mixed alcohol of an alcohol having 6 to 13 carbon atoms with trimellitic acid, is used as a component of the composition of the present invention because of its economical efficiency. is optimal. In the composition of the present invention, plasticizers commonly used for vinyl chloride polymers other than those mentioned above can be used in combination to impart various physical properties such as processability and strength. Examples include dibutyl phthalate, di-2-ethylhexyl phthalate, diisodecyl phthalate, butylbenzyl phthalate, and di-2-ethylhexyl adipate. The proportion of the polyester plasticizer or trimellitic acid ester plasticizer and other plasticizers used is not particularly limited, but in order to provide sufficient solvent extraction resistance, it is necessary to use 40% by weight of the total amount of plasticizer. % or more, preferably 50% or more, especially 70% or more of the former plasticizer. Therefore, the amount of plasticizer used depends on the type of plasticizer,
Although it varies depending on the processability of the vinyl chloride resin composition, the use of the molded product, etc.
30 parts by weight or more, preferably 50 parts by weight per 100 parts by weight
It is preferable that the amount is at least part by weight. The amount of plasticizer can also be increased or decreased by using diluents such as xylene, mineral spirits, kerosene, etc. If it is less than 30 parts by weight, it will be difficult to provide sufficient softness.
The texture of molded products, such as gloves, footwear, and leather, tends to deteriorate. Furthermore, when made into plastisol, it is likely to be difficult to shape due to its high viscosity. In addition to the above-mentioned components, the vinyl chloride resin composition of the present invention may contain processing aids such as heat stabilizers, fillers, diluents, and lubricants depending on the purpose.
Furthermore, a foaming agent can be added to form a foaming composition. Among these, as the heat stabilizer, those commonly used in the molding process of ordinary vinyl chloride polymers can be used, but among them, a heat stabilizer containing a zinc compound as a main component is most suitable. Further, the usage ratio thereof is not particularly limited, but may be about 0.5 to 8 parts by weight per 100 parts by weight of the resin component. The vinyl chloride resin composition of the present invention is prepared by maintaining the above-mentioned components at a temperature below which no crosslinking reaction occurs using a known mixing device such as a ribbon blender, a crusher, a Henschel mixer, or other mixer. A granular or powdery composition,
It can be made into sol-like compositions such as plastisol and organosol. Various molding methods can be employed for the composition of the present invention. For example, granular or powdered compositions
For injection molding, extrusion molding, compression molding, rotation molding, etc.
In addition, the sol-like composition is shaped by slush molding, rotational molding, dipping molding, coating, rotary screen, etc., and is heated at a temperature higher than the melting temperature of the composition, for example, in the range of 160 to 240°C, during or after shaping. A crosslinking reaction is carried out by heating to obtain a molded article. Specifically, footwear made of soft vinyl chloride resin is laminated by slush molding or rotational molding onto a base material such as cloth using a coating machine such as a knife coater to produce soft vinyl chloride resin artificial leather, flooring material, The wall covering can be formed by a rotary screen. The molded article obtained from the composition of the present invention has excellent rubber elasticity, and also has acetone, alcohol,
It has extremely good solvent extraction resistance against solvents such as dichloroethane, trichloroethylene, tetrahydrofuran, gasoline, benzene, toluene, xylene, nitrobenzene, cyclohexanone, other aromatic hydrocarbons, and linear hydrocarbons. The composition of the present invention will be explained in detail in Examples below, but the present invention is not limited to the following Examples unless the gist thereof is exceeded. Example 1, Comparative Example 1 The composition of the vinyl chloride resin composition in Examples and Comparative Examples was determined as shown below, and plastisol was prepared by continuously changing the ratio of polyester plasticizer and dioctyl phthalate. The plastisol was applied in the form of a sheet and heated at a temperature of 200℃ for 8 hours.
Allow to completely melt for minutes. The obtained sheet was left in trichlorethylene at 23°C for 3 days, then dried.
Weight reduction and hardness increase due to solvent extraction (softness resistance)
compared.

[Table] Coalescence Emulsion polymerization

[Table] The results of the tallate measurement are shown in Figures 1 and 2. FIG. 1 is a graph showing solvent extraction resistance, and FIG. 2 is a graph showing hardness increase after solvent extraction. In the figure, the horizontal axis shows the mixing ratio of polyester plasticizer (PE) and dioctyl phthalate (DOP), and the vertical axis shows the percentage of weight loss and the percentage of hardness increase. , 2 indicate Comparative Example 1, respectively. As is clear from the figure, the composition of the present invention using a crosslinkable copolymer has extremely excellent solvent extraction resistance compared to a composition using only a non-crosslinkable vinyl chloride polymer. It can be seen that there is little change in the hardness of the material itself. Furthermore, it is shown that the greater the blending ratio of the polyester plasticizer, the more remarkable the effect. Example 2, Comparative Example 2 Vinyl chloride polymer (1300) 50 parts by weight Crosslinkable copolymer (same as Example 1) 50 Tri-2-ethylhexyl trimellitate
100 Isophorone-based isocyanate crosslinking agent 3 Calcium-zinc stabilizer 3 Pigment 2 Soft vinyl chloride resin boots were manufactured from plastisol having the above composition by slush molding. These boots were dry-cleaned 20 times, and each time there was no change in hardness or shrinkage.
It had rubber elasticity. For comparison, the same procedure as in Example 2 was carried out in the case where the crosslinkable copolymer was not used and the vinyl chloride polymer was used at 100 parts, but the sample was cured and shrunk after dry cleaning. Example 3 Plastisol was prepared by replacing 100 parts by weight of the plasticizer in Example 2 with 70 parts by weight of the polyester plasticizer used in Example 1. Using the plastisol, cooking gloves were manufactured by dip molding. The obtained glove had excellent solvent extraction resistance and oil resistance, and had rubber elasticity. Examples 4 and 5 Vinyl chloride polymer 50 obtained by suspension polymerization
Parts by weight, 50 parts by weight of the crosslinkable copolymer used in Example 1 obtained by emulsion polymerization, 3 parts by weight of diisocyanate
1 part, 3 parts of a calcium-zinc stabilizer, and 2 parts of a pigment were mixed with 70 parts by weight of a polyester plasticizer (Example 4) and a trimellitic acid ester plasticizer (Example 5) to prepare a powdered vinyl chloride resin. A composition was obtained. Decorative buttons, emblems,
Decorative parts for clothing such as one-point items were manufactured by injection molding. After these were attached to clothing, the clothing was dry-cleaned several times, but the hardness was close to the initial hardness and no shrinkage occurred.

[Brief explanation of the drawing]

FIG. 1 is a graph showing the rate of weight loss of the composition due to solvent extraction, and FIG. 2 is a graph similarly showing the rate of change in hardness. In the figure, the horizontal axis shows the composition ratio of the plasticizer, and the vertical axis shows the weight loss rate and hardness increase rate. 1 shows the composition of the present invention, and 2 shows the composition of a comparative example.

Claims (1)

[Scope of Claims] 1. A composition comprising a vinyl chloride resin, a crosslinking agent for the vinyl chloride resin, and a plasticizer, wherein the vinyl chloride resin contains at least a portion of vinyl chloride and a hydroxyl group, a carboxyl group, or an epoxy group. or a vinyl chloride resin containing a vinyl chloride copolymer with a vinyl comonomer having an alkoxy group, and containing a polyester plasticizer or a trimellitic acid ester plasticizer as at least a part of the plasticizer. Composition. 2. The vinyl chloride resin composition according to claim 1, wherein the vinyl chloride copolymer is produced by emulsion polymerization or fine suspension polymerization. 3. The vinyl chloride resin composition according to claim 1 or 2, wherein the vinyl chloride resin composition is plastisol or organosol.