PROCESS FOR STABILIZING CRYSTALLINE ORGANIC PHOSPHITE OR PHOSPHONITE FROM EFFECT OF HYDROLYSIS, AND ORGANIC PHOSPHITE OR PHOSPHONITE STABILIZED FROM EFFECT OF HYDROLYSIS Russian patent published in 1999 - IPC

FIELD: chemical industry. SUBSTANCE: claimed process comprises introducing mixture comprising phosphite of phosphonite, solvent or mixture of solvents and 0.1-100 wt % amine with respect to phosphite or phosphonite heated to 50-100 C in the form homogeneous melt into liquid crystallization medium. As melt is introduced, medium temperature is maintained by 10-70 C lower then melt temperature. The claimed process improves stability of organic phosphites and phosphonites from effect of hydrolysis. The present invention also describes preparation of organic phosphite or phosphonite stabilized from effect of hydrolysis. Said organic phosphite or phosphonite has improved properties and are useful as thermostabilizers for synthetic polymers. EFFECT: more efficient stabilization process. 14 cl, 36 ex, 8 tbl