JPS624739A - Rigid transparent vinyl chloride resin composition hardly causing whitening - Google Patents

Abstract

PURPOSE:To provide the titled compsn. which gives moldings having excellent resistance to whitening, by blending a dialkyl citrate with a vinyl chloride resin. CONSTITUTION:0.001-0.03pts.wt., pref. 0.005-0.02pts.wt. 10-30C dialkyl citrate contg. not more than 30wt% at lest one member selected from among monoesters and triesters of citric acid and optionally, additives such as stabilizer (e.g. di-n-butyltin maleate), lubricant (e.g. stearic acid), plasticizer, antioxidant, ultraviolet absorber, antistatic agent, pigment, etc., are blended with 100pts.wt. vinyl chloride resin contg. at least 50wt% vinyl chloride (resin).

Description

Detailed Description of the Invention [Industrial Application Field] The present invention is directed to the treatment of hard transparent molded products made from a hard transparent vinyl chloride resin composition under contact with water, alcohol, alcohol aqueous solution, etc. or under high temperature and high humidity conditions. This invention relates to a vinyl chloride resin composition that is less likely to whiten in the atmosphere.

[Prior art/problems to be solved by the invention] Hard transparent molded products made from vinyl chloride resin compositions are used for containers, industrial boards, decorative boards, films, etc. that require glass-like transparency.
Widely used as sheets, etc.

However, these hard transparent molded products cannot be used with water, alcohol,
When products such as alcohol aqueous solutions are packaged or left in a hot and humid atmosphere for a long time, the surface becomes white and opaque, resulting in a significant loss of value of the molded product.

However, despite the strong demand for a method to prevent hard transparent molded products made from vinyl chloride resin compositions from whitening when in contact with water, alcohol, aqueous alcohol solutions, etc., or in high temperature and humid atmospheres, The reality is that no effective method for preventing whitening has yet been discovered.

The present invention has been made to prevent the above-mentioned whitening phenomenon.

[Means for solving problems]

In the present invention, citric acid dialkyl ester (alkyl group has 10 to 30 carbon atoms) is added in an amount of 0.001 to 100 parts (heavy parts, hereinafter the same) of a vinyl chloride resin composition.
This invention relates to a vinyl chloride resin composition containing 0.03 parts of hard transparent formulation and less whitening.

〔Example〕

The vinyl chloride resin used in the present invention refers to vinyl chloride resin, which contains vinyl chloride as a main component, that is, 50% (by weight) or more, with other components such as acrylic acid, methacrylic acid, maleic anhydride or Those esters,
Copolymers with nylidene chloride, vinyl acetate, alkyl vinyl ethers, alkyl vinyl ketones, ethylene, propylene, and other various known vinyl monomers, or at least one of these, for example, ABS resin,
It refers to a polymer blend with an impact reinforcing agent for vinyl chloride resin such as H8S resin, and the vinyl chloride content is 50% or more, and these may be used alone. May be used together.

In the present invention, the above vinyl chloride resin and citric acid dialkyl ester (the alkyl group is an alkyl group having 10 to 30 carbon atoms) are blended to prepare the hard transparent vinyl chloride resin composition of the present invention with less whitening. I am forced to do it.

The citric acid dialkyl ester referred to in the present invention includes those containing 30% or less of a mixture of citric acid monoester, citric acid tolyl ester, citric acid monoester, and citric acid triester in the citric acid ester, Not all citric acid esters need to be dialkyl esters.

If the citrate monoester content in the citric acid diester exceeds 30%, the transparency of molded products with hard transparent formulations will be inhibited, and if the citric acid monoester content exceeds 30%, the desired whitening prevention effect will be impaired. is no longer sufficient.

The alkyl groups of the citric acid dialkyl ester each have 10 to 30 carbon atoms, and those with less than 10 carbon atoms will have a markedly poor ability to prevent whitening of the resulting molded product, while those with more than 30 carbon atoms will cause the molded product to deteriorate. The transparency of the film is impaired, which is not desirable.

The blending amount of dialkyl citric acid ester per 100 parts of vinyl chloride resin is 0001 to 0.03 parts, and 0.000 parts to 0.03 parts.
0.005 to 0.02 part is preferred. The blending amount is 0.001
If the amount is less than 0%, the anti-whitening effect will not be sufficient, and
If the amount exceeds 0.3 parts, the transparency of the molded product itself will be impaired, which is not preferable.

The hard transparent formulation referred to in this specification is a formulation for obtaining a rigid transparent molded product by blending stabilizers, lubricants, and additives commonly used in the industry with vinyl chloride resin,
There is no particular restriction as long as it is a normal combination.

Examples of the above-mentioned stabilizers include di-n-butyltin maleate, di-n-octyltin maleate, and di-n-octyltin maleate.
-Butyltin bis(alkyl maleate), di-n-octyltin bis(alkyl maleate), di-n-butyltin bis(alkylthioglycolate), di-n-butyltin-β-mercaptopropionate, di-n-butyltin bis(alkylthioglycolate), n-octyltin bis(alkylthioglycolate), fatty acid salts such as cadmium stearate, barium stearate, calcium stearate, zinc stearate, etc.
Examples include epoxy compounds such as epoxidized soybean oil and epoxidized linseed oil, and organic phosphate esters such as tridecyl phosphite and trioctyl phosphite, and there are no particular limitations on the types and combinations thereof.

Examples of the lubricant include stearic acid, butyl stearate, glycerin monostearate, methylene bis-stearoamide, ethylene bis-stearoamide,
Examples of additives include stearyl alcohol and polyethylene glycol, and various other additives include plasticizers, antioxidants, ultraviolet absorbers, antistatic agents, and pigments. Dialkyl enoate has the ability to act as a lubricant. One of the features of the present invention is that it has scales that reduce the amount of lubricant when processed under the same molding conditions.

Specific examples of the hard and transparent compound composition that does not contain dialkyl citrate in the present invention include vinyl chloride resin, a tin-based stabilizer such as dioctyltin maleate, an impact modifier, a plasticizer such as DOP, and butyl stearate. Compositions containing lubricants such as esters, calcium stearate and zinc stearate to vinyl chloride resin.
Examples include compositions containing In-based stabilizers, impact modifiers, plasticizers such as epoxy soybean oil, and lubricants such as stearic acid.

There is no particular limitation on the blending method when a predetermined amount of dialkyl citrate is blended with the vinyl chloride resin in such a hard transparent compound, and the vinyl chloride resin of the present invention obtained There are no particular limitations on the method of molding the composition.

A molded article made from the vinyl chloride resin composition of the present invention hardly loses its transparency and does not become cloudy even under severe conditions such as being immersed in water at 60°C for 24 hours, 2 hours in 90℃ water or 60℃
It maintains its transparency even under even harsher conditions, such as being immersed in water for 72 hours at a temperature of It has significantly superior anti-whitening performance compared to non-whitening products.

The other physical properties of the molded product, such as thermal stability, tensile strength, elongation, impact strength, etc., are the same as those of the conventional product.

Next, the composition of the present invention will be explained based on Examples, but the present invention is not limited thereto.

Examples 1 to 7 and Comparative Examples 1 to 4 Vinyl chloride resin (310081 manufactured by Nippon Vinyl Chloride ■ 100 parts dibutyltin maleate (N2000C manufactured by Nitto Kasei ■) 3.0
5.0 parts D
OP 2.0 parts Butyl stearate 5 Citrate dialkyl ester shown in Table 1 The above blend was kneaded with a test roll at 165°C for 5 minutes,
A sheet with a thickness of 0.5 mm+ was prepared, and this sheet was roughly pressed at 170'C for 10 minutes to obtain a transparent test piece.

The obtained test piece was immersed in water adjusted to 60 ° C for 24 hours, then taken out of the water, air-dried, and the turbidity was measured using an ND-IV type colorimeter manufactured by Nippon Denshoku Kogyo ■. The degree of whitening was determined.

Turbidity is expressed by the following formula.

×100 The transparency of the test piece was expressed by the total transmitted light of the test piece before being immersed in water.

An appropriate amount of butyl stearate, which is a lubricant, is used to increase the viscosity of the sheet to the roll surface, i.e., increase the roll temperature from 170℃ in 5℃ intervals, and after 10 minutes of mixing at each temperature, take out the sheet. The determination was made based on the adhesion temperature, which is the temperature at which the adhesiveness disappears.

The results are shown in Table 1.

[Margins below] As is clear from the results in Table 1, molded articles obtained from vinyl chloride resin compositions containing a very small amount of dialkyl citrate have an excellent anti-whitening effect.

〔Effect of the invention〕

When a molded article is manufactured using the composition of the present invention, a molded article with good whitening resistance can be obtained.

Claims (1)

[Claims] 1. A hard and transparent formulation containing 0.001 to 0.03 parts by weight of citric acid dialkyl ester (alkyl group has 10 to 30 carbon atoms) to 100 parts by weight of vinyl chloride resin, resulting in less whitening. Vinyl resin composition.