| 摘要 |
Neopentyl phosphites having the formula <FORM:0996254/C2/1> where R is an alkyl, phenyl or alkylphenyl radical, e.g. phenyl, decyl, p-tert-butylphenyl, and p-methylphenyl neopentyl phosphites, are obtained by an ester exchange reaction, e.g. using triphenyl phosphite or trialkylphenyl phosphite and neopentyl glycol as starting materials. The preparation of p-methylphenyl neopentyl phosphite from neopentyl glycol and tricresyl phosphite in the presence of finely-divided sodium is described. The neopentyl phosphites are used for stabilization of cellulose esters (see Division C3).ALSO:A cellulose ester composition comprises a cellulose ester of a fatty acid containing 2 to 4 carbon atoms, and a neopentyl phosphite of <FORM:0996254/C3/1> where R is an alkyl, phenyl or alkyl phenyl radical. The cellulose ester is thereby stabilized against colour and molecular weight deterioration. Specified phosphites, which are made by ester-exchange reactions (see Division C2) are p-methyl phenyl, p-tert-butyl phenyl, decyl, and phenyl neopentyl phosphites. The composition, which may contain plasticizers and other stabilizers, preferably contains at least 0.01 parts of neopentyl phosphite e.g. 0.01-0.5 parts, per 100 parts of cellulose esters. Specified compositions contain (1) cellulose acetate butyrate, dibutyl sebacate, strontium, naphthenate, epoxidized soy-bean oil, phenyl neopentyl phosphite and decyl neopentyl phosphite; (2) cellulose acetate propionate, dibutyl sebacate, strontium naphthenate, epoxidized soy-bean oil, and phenyl neopentyl phosphite. |
