摘要
采用原硅酸乙酯和硅氮聚合物(KHCL) 为交联剂制备了两种室温硫化氟硅橡胶,通过TG、IGA 以及测定溶胶量等方法研究了两种氟硅橡胶在氮气下的降解动力学,并分别求出了降解速率和活化能.通过对比两种氟硅橡胶的热稳定性,阐述了硅氮交联剂对于提高氟硅橡胶热稳定性的作用机理.
Fluorosilicones are less stable than conventional methyl silicones because they are more likely to revert to low molecular weight cyclic products,especially in sealed circumstance.As for RTV fluorosilicone rubbers,they are usually vulcanized by ethyl silicate and diethylene diamine,and liable to suffer from reversion by water and catalyst and alcohol byproducts emit during vulcanization.Instead of ethyl silicate,one RTV fluorosilicone rubber was prepaired by using polysilazane KH\|CL as crosslinking agent without using diethylene diamine as catalyst.The thermal stability of fluoroislicone rubber crosslinked by KH\|CL (FSi\|B) was compared with fluorosilicone rubber crosslinked by ethyl silicate and diethylene diamine (FSi\|A) in sealed circumstance by TG\,IGA and solubility.The results showed that FSi\|B was much more stable than FSi\|A due to eliminating water and siloxy that can lead to reversion of fluorosilicone rubber.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
1999年第6期715-719,共5页
Acta Polymerica Sinica
关键词
热稳定性
室温硫化
氟硅橡胶
硫化
耐高温
Thermal stability,Room temperature vulcanization,Fluorosilicone rubber