膨胀珍珠岩及气相二氧化硅填充硅橡胶复合材料的制备与隔热性能

Preparation and Performance Regulation of Perlite and Fumed Silica Composited Silicone Rubber for Thermal Insulation Materials

研究珍珠岩基新型复合保温材料是开拓矿物材料应用领域的新课题.本工作研究了2种不同尺寸珍珠岩以及气相二氧化硅作为复合填料,分别以捏合工艺和直接混合工艺填充于乙烯基硅油或室温硫化硅橡胶,制备珍珠岩填充的复合硅橡胶保温板,通过检测不同产物的导热系数以及保温效果来评价其性能.结果表明:以捏合工艺制备的产品会降低珍珠岩的保温效果,主要原因是中空颗粒被捏合过程破碎;而以气相二氧化硅为主要填料制备的保温板不易成型,可成型产品最低导热系数为0.1728 W·m^(-1)·K^(-1);当以珍珠岩+气硅粉在硅橡胶中的质量比为37.5%时,产品导热系数为0.0349 W·m^(-1)·K^(-1),产物厚度为2.5 cm、250℃单侧加热4 min后,背面温度为67℃,基本满足在新型烟具等特种保温隔热应用要求.

Developing some thermal insulating composite materials based on perlite is a subject to expand the application of mineral materials.In this paper,the vinyl silicone oil or room-temperature vulcanized silicone rubber was mixed with two kinds of perlite with different sizes and fumed silica as fillers through a kneading process and a direct mixing process,respectively.Some composite silicone rubber insulation boards were prepared and evaluated by the thermal conductivity and insulation performance.The results show that the product prepared by the kneading process has resulted in a reduced heat preservation ability of perlite,probably due to the broken hollow particles.The insulation board prepared with fumed silica as a main filler is difficult to form their shape,and the minimum thermal conductivity is 0.1728 W·m^(-1)k^(-1)for the formed sample.When a mass ratio of perlite and fumed silica in silicone rubber is 37.5%and the product thickness is 2.5 cm,the minimum thermal conductivity is 0.0349 W·m^(-1)k^(-1),and the back-side temperature is 67℃C after heating at 250℃for 4 min,which basically meets the application requirements of thermal insulation materials for tobacco facility.