JPS61151263A - Method for stabilizing polycarbonate polyol - Google Patents

Abstract

PURPOSE:To prevent MW from being lowered by prolonged heating, by blending a small quantity of an org. phosphorus ester compd. with an aliph. polycarbonate polyol. CONSTITUTION:A 0.1-0.001wt% org. phosphorus ester is blended with an aliph. polycarbonate polyol obtd. by reacting a carbonate component such as dimethyl carbonate or diphenyl carbonate with a diol component such as 1,6-hexanediol or 1,4-butanediol, thus improving thermal stability. Examples of the org. phosphorus esters are org. acidic phosphates such as methyl acid phosphate; org. phosphites such as triphenyl phosphite; and org. phosphates such as triphenyl phosphate.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to the thermal stability of polycarbonate polyols.

Although polycarbonate polyol has excellent heat resistance and hydrolysis resistance, its molecular weight still decreases due to long-term heating.

This kind of deterioration is thought to be caused by the catalyst used in the reaction production, and for aromatic dicarboxylic acid polyesters, etc., a method is used to deactivate the reaction catalyst by adding a phosphoric acid compound at the end of the reaction, but this is not the case. The invention prevents thermal degradation of aliphatic polycarbonate polyols regardless of the presence of a catalyst.

That is, by adding an organic phosphoric acid ester compound, an aliphatic polycarbonate polyol with little heat resistance deterioration can be obtained.

As a method for producing carbonate diol with less deterioration, a non-catalytic reaction as shown in the example of Japanese Patent Publication No. 46-42384 is preferable, but compared to the example using a catalyst, the non-catalytic reaction also deteriorates due to heating. It didn't improve much.

However, the present inventor has discovered that by adding an organic phosphoric acid ester compound to the polycarbonate polyol obtained by such a non-catalytic reaction, the polycarbonate polyol can withstand long-term heating.

That is, the present invention provides a polycarbonate, ttv, characterized in that 0.1 to 0.001% by weight of an organic phosphoric acid ester compound is blended with respect to an aliphatic polycarbonate polyol.
This relates to a method for stabilizing oars.

Examples of organic phosphoric acid ester compounds that can be used in the present invention include organic acid phosphoric acid esters such as methyl acid phosphate, butyl acid phosphate, dibutyl phosphonate, octyl phosphate, and dioctyl phosphate, triphenyl phosphite, and tris Organic phosphites such as chloroethyl phosphite and tristridecyl phosphite, dibutyloptylphosphonate, phosphonic acid esters of di(octyl)octyl phosphonates, triphenyl phosphate, tricresyl phosphite Organic orthophosphoric acid esters such as phate, trimethyl phosphate, tributyl phosphate, tributyl phosphate, trioctyl 7 phosphate, and trilauryl phosphate can be mentioned.

These organic phosphoric acid esters are added in a ratio of 0.1 to 0.0% to the aliphatic polycarbonate polyol. Added 1% by weight of OO,
It is a uniform mixture.

No effective difference was observed even when the amount added was 0.1% or more, and 0.1% or more was added. If OO' is less than 1%, no significant effect can be expected.

Examples of the aliphatic polycarbonate polyol that can be used in the present invention include carbonates such as dialkyl carbonates such as dimethyl carbonate, diethyl carbonate, and dibutyl carbonate, ethylene carbonate), dialkylene carbonates such as 1,2-propylene carbonate, and diphenyl carbonate. , diaryl carbonate and dihydroxy compounds such as diaryl carbonate, 1,4-butanediol, 1
．． 5-bentanediol, 3-methyl-1,5-bentanediol, 1,6-hexanediol, 1.7-heptanediol, 1,8-octanediol, 2-ethyl-1,6-hexanediol, 1. 9-nonanediol, 1.10-decanediol, 1.12-dodecanediol, 1,4-dimethylcyclohexanediol,
3(4)j, 8(9)-bis-(hydroxymethyl)-tricyclo(5+2*1sO"')decane, etc., and can be obtained by reacting these alone or with a mixture.

Next, the present invention will be explained in detail with reference to Examples.

Example 1 Diphenyl carbonate 3400f and 1,6-hexanediol 20B29 were mixed into a 5I tube equipped with a thermometer, a stainless steel stirrer, a branched fractionator tube, and a carbon dioxide gas inlet tube. Transfer to a glass reaction vessel. The reaction mixture was heated to 155°C with stirring.
shall be. Then apply ``vacuum'' to distill the phenol.
Start with a pressure of about 00■Hf. The pressure was reduced to 25 trmHf over 24 hours while keeping the temperature at 155°C. Next, slowly raise the temperature to 200℃.
and the pressure was reduced to 12 mHt over 10 hours. After reacting for about 14 hours while maintaining the same temperature and pressure,
Aerate carbon dioxide gas at a rate that maintains a vacuum level of 8 mHf.
After some time, the reaction was considered complete.

The polycarbonate polyol thus obtained had an average molecular weight of 2,000. The polyol was heated to 100°C.
After cooling, 0.04% by weight of triphenylphosphite was added and mixed. A heat deterioration test was conducted by leaving the product in an open gear at 200° C. for 28 days. The results are shown in Table 1.

Example 2 0.0 to the polycarbonate diol produced in Example 1
47% of triphenyl phosphate was added, and a heat deterioration test was conducted in the same manner as in Example 1, and the results are shown in Table 1.

Example 3 0.04% by weight of polycarbonate diol with a molecular weight of 1000 produced using diethyl carbonate 1928 f, 1.6 hexanediol 2075 f and transesterification catalyst tetraptyl titanium, -) 0.075 f.
dibutyl acid phosphate was added, and a heat deterioration test was conducted in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1 A heating test is conducted on the polycarbonate according to Example 1 without any additives. The results are shown in Table 1.

Comparative Example 2 A heating test was conducted on the polycarbonate according to Example 3 without any additives. The results are shown in Table 1.

Table 1 That is, by adding the organic phosphoric acid ester compound, it was possible to prevent the molecular weight from decreasing due to heating.

Special pestle applicant Japan Polyurethane Industry Co., Ltd.

Claims (1)

[Claims] 0.1 to 0 for aliphatic polycarbonate polyol
．． 1. A method for stabilizing polycarbonate polyol, which comprises blending 0.001% by weight of an organic phosphoric acid ester compound.