The thermal stabilites of silicone gums containing cyclodisilazane

(SCD)

E=Me

Ph

Were studied in comparison with methyl and phenyl silicone gum by the method of TGA. IGA. GC. and GC-MS. The initial temperature of the weight loss of SCD is 150-200℃ higher than that of methyl silicone gum

the wedght loss is 10-20 times less than that of methyl as well as phenyl silicone polymer. Based on both the GTA and the IGA data

the presence of cyclodislazane in SCD enhances the resistance of the main chain to degradation and the weight loss remains almost the same as the number (x) of Me2SiO groups in SCD changes. Outstanding stability of this material makes them to be used potentilly as high-temperatuse elastomers. Accoding to analysis of the decompsed products a two steps mechanisum of degradation is proposed.