碳化硼/有机硅复合材料的制备及相关性能研究

摘要

以有机硅树脂为基体,用硅烷偶联剂KH550表面改性的碳化硼作填料,在铂催化作用下,制备了碳化硼/有机硅复合材料.分别采用DLS、SEM、FT-IR、热膨胀系数仪、TG、硬度计、电子万能试验机等对改性前后碳化硼的粒径、形貌、分子结构变化及碳化硼/有机硅复合材料相关性能进行表征.结果表明,改性后的碳化硼颗粒表面接枝上KH550,改变了粉体的表面性质,增强了无机碳化硼与有机硅树脂界面相容性,降低了二者界面张力.制备的复合材料拉伸强度、邵氏硬度随无机填料质量分数的增加而增大,复合材料的拉伸强度达8.62 MPa,耐温达300℃.%Under the action of platinum catalysis,boron carbide/organic silicone composites were prepared by u-sing organic silicone resin as matrix and boron carbide modified with silane coupling agent KH550 as filler.The particle size,morphology and molecular structure of boron carbide before and after modification and related properties of boron carbide/organic silicone composites were characterized by DLS,SEM,FT-IR,thermal ex-pansion coefficient instrument,TG,hardness tester and electronic universal testing machine.The results showed that KH550 was successfully grafted onto the surface of boron carbide,which changed the surface prop-erties of the powder,enhanced the interfacial compatibility and reduced the interfacial tension between the inor-ganic boron carbide and the organic silicone resin.The tensile strength and shore hardness of the composites in-creased with the increase of the mass fraction of the inorganic fillers,and the tensile strength could reach up to 8.62 MPa.It could resist to high temperature of 300 ℃.