Study On The Preparation Of Silicon Rubber/Phenolic Resin Thermal Insulation Composites And Its Properties

Improving energy utilization rate is great significant for energy-saving and emission-reduction for our country.And the use of high temperature insulation materials is mean to improve the current energy utilization rate in China.In this paper,using phenolic resin,boron phenolic resin and polybenzoxazine resin as high temperature resistant heat insulation resin,high temperature vulcanized silicon rubber as high temperature resistant heart insulation matrix for preparing silicone rubber/phenolic resin composite by blending method.The mechanical property experiments were conducted,and the ablation property and preparation of composites were investigated by DSC,SEM,oxygen acetylene flame.The effects of MgO(ZrO2)on the ablation properties and mechanical properties of silicone rubber/benzene resin composites were studied by the same test method.Ablation structure of silicone rubber/polybenzoxazine resin composite was investigated by FT-IR and Raman.Experimental results show that:(1)The optimal ratio of silicone rubber/polybenzoxazine resin high temperature resistant heat insulation composite is that:silicone rubber 100 phr,polybenzoxazine resin 20 phr.The line ablation rate is 0.057 mm/s,adiabatic index is 8.3 s/mm,tensile strength is 2.74 MPa,elongation at break is 274.6%.(2)The comprehensive properties of silicone rubber/polybenzoxazine resin/ZrO2 high temperature resistant heat insulation composite system is better than that of silicone rubber/polybenzoxazine resin/MgO high temperature resistant heat insulation composite system.But silicone rubber/polybenzoxazine resin high temperature resistant heat insulation composite system has better comprehensive properties than silicone rubber/polybenzoxazine resin/ZrO2 high temperature resistant heat insulation composite system.(3)The comprehensive properties of silicone rubber/polybenzoxazine resin/ZrO2 high temperature resistant heat insulation composite with 10 phr ZrO2 has the line ablation rate of 0.065 mm/s,adiabatic index of 7.8 s/mm,tensile strength of 1.43 MPa,and elongation at break of274.6%.(4)After ablated in oxygen acetylene flame,the ablation layer of silicone rubber/polybenzoxazine resin composite is divided into three obvious layers as surface ceramic layer,pyrolysis carbonization layer and base layer.The main chemical components of surface ceramic layer and pyrolysis carbonization layer are SiO2,SiC and C.