JPS601262A - Stabilizer for halogen-containing resin - Google Patents

Abstract

PURPOSE:To improve resistance to weather and heat and to eliminate a problem of exudation toward the surface of a molded film, by incorporating a specified organophosphorus compd. in a hologen-contg. resin. CONSTITUTION:0.01-5pts.wt., pref. 0.1-2pts.wt. organophosphorus compd. of the formula (wherein R1, R2 are each a 1-3C alkyl) is blended with 100pts.wt. halogen-contg. resin. Other stabilizer, stabilizing aid, antioxidant and ultraviolet light absorber may be used together with said organophosphorus compd. When the organophosphorus compd. is used together with Ca-Zn or Ba-Zn salt of a fatty acid, excellent weather resistance can be imparted and exudation is little caused. Examples of the organophosphorus compd. are tris (2,4-xylenyl) phosphite and tris (2,4-diethylphenyl) phosphite.

Description

Detailed Description of the Invention The present invention is based on the following general formula (wherein R1 and R2 are alkyl groups having 1 to 3 carbon atoms,
The alkyl groups may be the same or different, and the position of the substituent is not limited to the meta or para position.The inclusion of an organic phosphorus compound (the alkyl group may be the same or different, and the position of the substituent is not limited to the meta or para position) provides weather resistance -- that is, the film does not become stained during natural exposure. less, heat resistant,
This invention relates to a stabilizer for halogen-containing resins, particularly for vinyl chloride-containing resins, which has improved discharge on the film surface and the appearance of spots.

Halogen-containing resins are generally produced in the presence of oxygen by the action of physical energy such as heat or light to form carbonyls through thermal oxidation or photooxidation, or to form mainly conjugated double bonds, crosslinking, etc.
Extensive changes leading to molecular chain scission, ie deterioration, occur, resulting in discoloration, decreased mechanical strength, etc. Particularly in the case of halogen-containing resins, the deterioration caused by dehydrohalogenation is extremely large.

Therefore, in order to suppress deterioration during heat processing or photodeterioration, stabilizers such as metal soaps and organic tin stabilizers, as well as stabilizers such as antioxidants, ultraviolet absorbers, epoxy compounds, organic phosphites, and organic phosphates, are used. It must be added in combination with a chemical additive. It is also a known fact that a synergistic effect can be expected by using these auxiliary agents in combination. However, with known stabilizing aids, unfavorable phenomena have been observed in terms of heat processability, physical and chemical properties after processing, and light stabilization, and so far no satisfactory product has been obtained.

For example, in the case of known organic phosphites, the phosphite itself is easily hydrolyzed, and when a large amount is added, a phenomenon of ejection onto the sheet surface occurs. Furthermore, in combination with an epoxy resin to improve heat resistance, there are drawbacks such as appearance of bumps on the sheet surface and poor weather resistance.

The object of the present invention is to provide a new stabilized halogen-containing resin composition by finding an organic phosphorus compound that improves the drawbacks seen in the above-mentioned phosphites.

In other words, the present inventors have conducted many years of research and found that the organic phosphorus compound represented by the above general formula has thermal discoloration prevention properties, particularly does not stain the film during natural exposure, has excellent weather resistance, and does not cause discharge or blistering on the film surface, and can be applied to resins. The present inventors have discovered that the present invention is extremely advantageous for practical use as a halogen-containing resin because it has excellent compatibility with other resins and is stable against hydrolytic action.

The amount of the organic phosphorus compound used in the present invention is usually 0.01 to 5 parts by weight per 100 parts by weight of the halogen-containing resin.
Particularly preferably 0.1 to 2 parts by weight, the organic phosphorus compound of the present invention may be used in combination with other commonly known stabilizers and stabilizing aids,
It can be used in combination with antioxidants and ultraviolet absorbers. These known stabilizers include Ba, Zn, Ca, M
fatty acid salt of g, carboxylate of Sn, RzSn, etc.
These include mono- or diester carboxylates, mercaptides, and mercapto acid esters. In particular, when the organic phosphorus compound of the present invention is used in combination with a Ca--Zn or Ba--Zn fatty acid salt, it provides extremely superior weather resistance than known organic phosphorus compounds, and moreover, the discharge phenomenon hardly occurs. Stabilizing aids used in combination include epoxy compounds and other known organic phosphoric acid ester polyhydric alcohols. Furthermore, the organic phosphorus compound of the present invention can also be used in combination with other additives used as additives for halogen-containing resins, such as lubricants, fillers, lubricants, surfactants, etc.

In addition, the halogen-containing resin in the present invention includes polyvinyl chloride, polyvinylidene chloride, chloroprene, or a copolymer of these monomers with other polymerizable monomers,
Polymer resins that are chlorinated after polymerization, such as chlorinated polyethylene,
and graftomers based on these resins, and synthetic resins made by blending them.

Examples of the organic phosphorus compounds of the present invention having such excellent performance include tris(2-4 xylenyl) phosphite, tris(3-5 xylenyl) phosphite, and tris(
2-3 xylenyl) phosphite, tris (2-4 diethyl phenyl) phosphite, tris (3-5 diethyl phenyl) phosphite, tris (2-3 diethyl phenyl) phosphite, tris (2-4 dipropylphenyl) Phosphite, Tris (3-5 dipropylphenyl) phosphite, Tris (2-3 dipropylphenyl phosphite, Tris (2-methyl 4 ethyl phenyl) phosphite, Tris (2 methyl 4 propylphenyl) phosphite, Tris (2 -ethyl 4-propylphenyl)
Such as phosphite.

Further, the organic phosphorus compound of the present invention may be produced by any method, but one example is as follows.

Production Example 3-5 40.4 g of xylenol is placed in a flask, and 13.7 g of phosphorus trichloride is added dropwise over an hour at 50 to 60° C. while stirring to react.

Next, the temperature is raised to 60°C to 100°C to complete the reaction.

The excess 3-5 xylenol was then removed under reduced pressure and filtered to yield tris(3-5 xylenyl)phosphite.

Phosphorus content: Theoretical value: 7.83% Actual value: 7.79% Yield: 99.5% Appearance: Pale yellow liquid The organic phosphorus compound of the present invention, which has excellent performance, will be described below with reference to Examples. The present invention is not limited to these examples. Note that parts in the examples indicate parts by weight.

Example 1. 100 parts of polyvinyl chloride resin with a degree of polymerization of 1300, 45 parts of dioctyl phthalate, 2.0 parts of glycidyl ether type epoxy resin of bisphenol A, and 0 parts of zinc stearate.
．． 7 parts of calcium stearate, 3 parts of tricresyl phosphate, and 1.5 parts of sorbitan monopalmitate as a surfactant, 1.0 part each of the phosphites of the present invention and existing phosphites were added and mixed thoroughly. Then, the sheet was kneaded for 5 minutes with a 6-inch roll at 165°C to produce a sheet. Next, this sheet was kneaded with a 8-inch roll at 180°C to a thickness of 0.1 mm.
Films of various thicknesses were prepared and subjected to discharge tests, spot tests, and natural exposure tests. The test results are shown in Table 1.

Table 1. The discharge and spot tests were performed using a 0.1 mm film (5 cm x 7 mm).
The results were obtained by stacking 10 sheets of 5cm) in a flan container at 60°C and 90% temperature.

In addition, the deterioration criteria for each test are as follows.

Example 2. 100 parts of polyvinyl chloride resin with a degree of polymerization of 1300, 45 parts of dioctyl phthalate, 1.0 part of glycidyl ether type epoxy resin of bisphenol A, and 0.0 parts of zinc stearate.
Add 1.0 part each of the present invention and existing phosphites to 7 parts barium stearate and 0.3 parts, mix thoroughly and knead for 5 minutes with a 6-inch roll at 165°C to form a 1 mm thick sheet. Created. Next, heat each film to 190℃.
Heat treatment was performed in a gear aging tester to examine the time until blackening. In addition, a 0.1 mm thick film was prepared from the light sheet using an 8-inch roll at 180° C., and the film was subjected to a natural exposure test.

The results are shown in Table 2.

Table 2

Claims (1)

[Scope of Claims] A stabilized halogen-containing resin composition characterized by containing an organic phosphorus compound represented by the general formula. (In the formula, R1 and R2 are alkyl groups having 1 to 3 carbon atoms,
The alkyl groups may be the same or different, and the position of the substituent is not limited to the meta or para position. )