JPH0967490A - Vinyl chloride resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition excellent in thermal stability in its molding processing and in chalking resistance of the molded products thereof. SOLUTION: The resin composition comprises 100 pts.wt. of a vinyl chloride resin, a total of 0.005-1 pt.wt. of a copper o,o'-dialkyldithiophosphate and/or stannous acetate, and 0.01-5 pts.wt. of ethylenediaminetetraacetic acid, and pref. a coloring ingredient. When compared to conventional such compositions, this resin composition is excellent in thermal stability during its long-term molding processing under heating and weatherability of the molded products thereof, in particular, can suppress chalking of the molded products thereof over a long period.

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 composition excellent in weather resistance, particularly choking resistance, and more particularly to a colored vinyl chloride resin composition.

[0002]

2. Description of the Related Art Vinyl chloride resin is often used outdoors as a molded product such as a pipe, a rain gutter, a deck material, a window frame or the like, which is colored with a pigment or the like.

However, when a colored molded article is exposed to the outside, not only the discoloration and fading of the color but also the so-called chalking phenomenon (whitening phenomenon) occurs, in which the surface of the portion exposed to the sunlight discolors white like a powder. However, there is a problem that the appearance is significantly impaired and the mechanical strength is also reduced.

Conventionally, in order to improve such drawbacks, heat stabilizers such as metal soaps, lead compounds and organotin compounds, as well as ultraviolet absorbers, antioxidants, plasticizers, lubricants, and Molded articles of vinyl chloride resin have been made by selectively adding a filler and a colorant, and adding a choking inhibitor such as a metal salt of naphthenic acid, a nickel chelate complex compound, and a metal salt of thiocyanate.

Further, o, o'-shown in JP-A-1-131267 or JP-A-5-287148.
The addition of copper dialkyldithiophosphate or metal salt of dialkyldithiocarbamate has also been carried out to suppress chalking for a longer period of time than conventional ones.

[0006]

However, if an attempt is made to suppress choking, the thermal stability of the vinyl chloride resin will decrease, and thermal decomposition during molding cannot be avoided to some extent.
Therefore, there is a problem that the original effect of the anti-choking agent cannot be exhibited in a molded product, and a product which is sufficiently satisfactory has not yet been provided.

[0007]

As a result of intensive studies to solve the above problems, the present inventor has found that o, o'-dialkyldithiophosphoric acid copper and / or acetic acid diacetate can be added to vinyl chloride resin at a specific composition ratio. By adding stannous and ethylenediaminetetraacetic acid, it was found that a vinyl chloride resin composition having good thermal stability and suppressing the choking of molded articles for a long period of time as compared with the conventional one was obtained, and completed the present invention. Came to do.

That is, the present invention is based on 100 parts by weight of a vinyl chloride resin, 0.005 to 1 part by weight of o, o'-dialkyldithiophosphate and / or stannous acetate alone or in total, and ethylenediamine. 0.01 to 5 tetraacetic acid
By including the parts by weight, it is possible to provide a vinyl chloride resin composition which is excellent in thermal stability during molding and in which the whitening phenomenon is significantly suppressed.

The o, o'-dialkyldithiophosphate copper used in the present invention has, for example, 3 carbon atoms as an alkyl group.
Examples thereof include those having 10 to 10 linear or branched alkyl groups, and among them, o, o'-di-n-butyldithiophosphate copper and o, o'-di (2-ethylhexyl) dithiophosphate copper are preferred. .

The vinyl chloride resin which is the subject of the present invention is a homo- or copolymer of vinyl chloride and a chlorinated vinyl chloride resin. These resins are mixed with metal soaps, lead compounds, organotin compounds, UV absorbers, UV stabilizers, lubricants, fillers, reinforcing agents, plasticizers, colorants, etc., which are usually added during use. Needless to say, there is no problem.

The amount of o, o'-dialkyldithiophosphate copper and / or stannous acetate used in the present invention, alone or in total, is 0.005 per 100 parts of vinyl chloride resin.
1 to 1 part by weight, preferably 0.05 to 0.5 part by weight, but when the vinyl chloride resin is colored in a bright color,
By reducing the proportion of stannous acetate, bright colors can be retained for a long period of time.

The amount of ethylenediaminetetraacetic acid used is in the range of 0.01 to 5 parts by weight, preferably 0.05 to 2 parts by weight, per 100 parts of vinyl chloride resin. As a method of mixing these in a vinyl chloride resin, o, o'-dialkyldithiophosphoric acid and / or stannous acetate and ethylenediaminetetraacetic acid may be directly added and mixed to the vinyl chloride resin, or a pigment or the like may be added. What was mixed beforehand with other additives may be added and mixed with the resin.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is as described above. Therefore, in carrying out the present invention, in 100 parts by weight of a vinyl chloride resin, one of o, o'-dialkyldithiophosphate copper and stannous acetate is used. Either or both of them are added in an amount of 0.005 to 1 part by weight, preferably 0.05 to 0.5 part by weight, and 0.01 to 5 parts by weight of ethylenediaminetetraacetic acid.
By weight, preferably 0.05 to 2 parts by weight is added, and if necessary, a coloring component for coloring a desired color and other various additives are added, and the mixture is kneaded by heating to obtain, for example, a resin composition for molding. .

Further, a so-called masterbatch is prepared in advance by adding other components of the present invention other than the vinyl chloride resin to the vinyl chloride resin or other suitable carrier resin in a high compounding ratio, and this is a large ratio. It is also possible to heat and knead with the vinyl chloride resin to produce the desired resin composition.

[0015]

EXAMPLES The present invention will be described more specifically by showing Examples and Comparative Examples below. All parts in the examples are parts by weight.

Examples 1 to 10 Vinyl chloride resin 100 parts, (Polymerization degree 1100) calcium stearate 0.5 part, zinc stearate 0.5 part,
0.1 parts of dibutyltin dimalate, o, o 'for 1 part of rouge
Copper dialkyldithiophosphate and / or stannous acetate and ethylenediaminetetraacetic acid were blended in the number of parts shown in Table 1. This was uniformly dispersed and mixed, and then kneaded with two rolls at 180 ° C. for 3 minutes to obtain a sheet having a thickness of 1.5 mm.

This sheet was placed in an oven at 190 ° C., a thermal stability test was conducted, and the time until blackening was measured. Further, a sheet prepared in the same manner was formed into a 1 mm thick sheet by a hot press at 185 ° C. and exposed outdoors. After 12 months, 24 months and 30 months of exposure, the color of the test piece was measured and the degree of chalking was measured by ΔY. ΔY is XYZ
Using the indicated Y value (corresponding to the brightness), it shows the difference between the initial test piece state and the Y value of the test piece after exposure for a predetermined period,
The larger the number, the more pronounced the choking. Table 1 shows the results.

Example 11 A sheet was prepared with the same composition as in Examples 1 to 10 except that 0.1 part of carbon black was additionally mixed as a colorant, and the thermal stability and the degree of choking were measured. The results are shown in Table 1.

Comparative Examples 1-4 Except that stannous acetate and ethylenediaminetetraacetic acid were not used together, the compounding parts of dibutyltin dimaleate were increased as shown in Table 1 or dibutyldithiocarbamate nickel was used. A sheet was prepared with the same composition as 1 to 10 by the same operation, a thermal stability test and outdoor exposure were performed, and the blackening time and ΔY were similarly measured. Table 1 shows the results.

[0020]

[Table 1]

[0021]

As is apparent from the above points, the present invention has better thermal stability than conventional ones, prevents thermal decomposition during long-time heat molding processing, and has a long-term weather resistance of molded products. It is possible to provide a vinyl chloride resin composition that has excellent properties and can significantly suppress choking of a molded product.

Claims (2)

[Claims] [Claim 1] 100 parts by weight of a vinyl chloride resin,
A vinyl chloride resin composition containing 0.005 to 1 part by weight in total of o, o'-dialkyldithiophosphate and / or stannous acetate, and 0.01 to 5 parts by weight of ethylenediaminetetraacetic acid. Stuff. 2. The vinyl chloride resin composition according to claim 1, which contains copper o, o′-dialkyldithiophosphate and / or stannous acetate, and ethylenediaminetetraacetic acid and a coloring component.