Preparation Of Carbon Fiber/Silicon Resin Composite Under Medium Temperature And Its Properties Study

Silicon resin has many excellent properties of organic and inorganic matter, especially its great heat-resistant, weathering resistance and dielectric properties make silicon be applied in all fields. In thethermalprotection field, silicon is one kind of excellent matrix of composite. Which can retain mechanical properties at high temperature and adapt to the harsh work environment.KH550and KH560silane coupling agents were used to modified carbon fiber,the carbon fiber’s invasion and reactivity was characterized with X-ray photoelectron spectroscopy (XPS), dynamiccontactangle, Dynamic invasive and differential scanning calorimetry (DSC). The results showed that modifid carbon fiber has better invasion and reactivity and KH550has better performance.Tetraethylenepentamine,H256,dibutyltin dilaurate, Dow Corning15catalyst and KH-CL were choosed, studies on effect on gel content of silicon resin by using one kind of catalyst and combining different kinds of catalyst. It was shown that catalytic curing agent can’t achieve good result, when tetraethylenepentamine and KH-CL were used0.4%and5%of pure silicon resin weight, content of silicon resin reached97%,lower1%than resin cured at high temperature. Thermostability of silicon was studied by TG,the result of TG shown that silicon cured at150℃and250℃had similar thermostability.Modified fiber was used to prepare CF/silicon composite undermedium temperature, studied on effect of mechanical properties of composite in room temperature and high temperature. The fracture morphology of composite was detected by scanning electron microscope (SEM),results indicated that modified fiber was good for improving mechanical property of composite in room temperature.