摘要
本文研究了聚硅氧烷在硅氮化合物或二苯基二羟基硅烷、水以及它们同时存在下的热稳定性。硅氮化合物能使聚硅氧烷在350℃的热稳定性大大提高;而二苯基二羟基硅烷和水能促进硅氧烷主链的降介,但同时有硅氮化合物存在,这种促进作用将会消失。所以硅氮化合物能阻止由硅羟基和水引起的降介。同时也是获得耐350℃聚硅氧烷的简便方法。
The thermal stability of polydiorganosiloxanes (PDOS) was studied in the presence or absence of silicon-nitrogen compounds (S-N) and/or Ph2Si(OH)z, water in nitrogen. It was found that in the presence of certain S-N the weight loss of PDOS decrease from 18% to 1.5% and the residual molecular weight of PDOS increases from 5.4×105 before heating to 6.7×105 at 350℃ for 24 hr. On the contrary, the residual molecular weight decreases from 5.4±105 to 1.7±105 when in the absence of S-N. Experimental results show that the weight loss of PDOS increases from 18% to 65% in the presence of certain Ph2Si(OH)2 or water at 350℃ for 24 hr., however, the weight can be decreased to 2-3% when the Ph2Si(OH)2 or water is added simultaneously with the S-N to the PDOS.This means that the S-N can prevent siloxane chain degrdation caused by SiOH groups or water at high temperature. The S-N may play a role that removes SiOH groups and water in improving thermal stability of PDOS. This gives a simple method to obtain polyorganosiloxanes. resistant to temperature of 350℃
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
1989年第1期46-51,共6页
Acta Polymerica Sinica
关键词
硅氮化合物
聚硅氧烷
热稳定性
Thermal Stability of Polydi organosiloxanes, Silicon nitrogen Compounds,Diphenylsilanediol, Water
