Structure and properties of addition type liquid silicone rubber crosslinked and modified by hexa(2-allylphenoxy)cyclic triphosphonitrile derivatives
To improve the properties of liquid silicone rubber(SR),an active hexa(2-allylphenoxy)cyclic triphosphonitrile derivative modifier(HAPPCP)was designed and synthesized,and the effects of HAPPCP on the mechanical properties,thermal stability,ablation resistance,and flame retardancy of addition type SR were investigated.The results showed that,compared with the unmodified SR,the tensile strength and elongation at break of 3 phr HAPPCP-modified addition type SR were improved by 40.5％and 204.4％,respectively,and the mass ablation rate and linear ablation rate were reduced by 19.90％and 55.70％,respectively.When 5 phr of HAPPCP were added,the mass residual rate at 800℃ increased from 18.86％to 30.15％.The flame retardancy of the HAPPCP-modified addition type SR was improved,turning it from a flammable to a combustible material.The total heat release rate,the peak value of the heat release rate,the amount of smoke release and the hazardous level of modified SR all reduced in the combustion process.
万方数据
维普
