偶联剂对聚丙烯/鳞片石墨复合材料的影响

Effect of Coupling Agent on Polypropylene/Flake Graphite Composites

分别采用硅烷偶联剂KH-560,KH-570和钛酸酯偶联剂NDZ-101,NDZ-201对石墨(FG)进行表面改性处理,再通过混炼,模压制备了聚丙烯(PP)/FG复合材料。研究了偶联剂的种类及用量对PP/FG复合材料力学性能、热导率和热性能的影响。结果表明:使用偶联剂处理FG,能够改善与PP的相容性,提高了PP/FG复合材料的力学性能与热性能,但复合材料的热导率略有下降,钛酸酯偶联剂NDZ-201处理效果最好。随着NDZ-201用量的增加,复合材料的拉伸强度、弯曲强度、拉伸弹性模量和断裂拉伸应变呈先增大后减小的趋势,而弯曲弹性模量逐渐减小,断裂弯曲应变逐渐增大。当NDZ-201的用量为0.7%,FG含量为70%时,复合材料的拉伸强度与弯曲强度分别达到33.1 MPa和52.3 MPa,复合材料的热导率为5.04 w/(m·K),较未添加NDZ-201的复合材料的熔点提高了2℃;在质量损失10%时的热分解温度提高了2.86℃。

Graphite(FG)was modified by silane coupling agents KH-560,KH-570 and titanate coupling agents NDZ-101,NDZ-201,respectively.Polypropylene(PP)/FG composites were prepared by mixing and die pressing.The effects of the types and amounts of coupling agents on the mechanical properties,thermal conductivity and thermal properties of PP/FG composites were studied.The results show that FG treated with coupling agent improve the compatibility with PP and improved the mechanical and thermal properties of PP/FG composites,but the thermal conductivity of the composites decrease slightly,titanate coupling agent NDZ-201 has the best treatment effects.With the increase of NDZ-201 content,the tensile strength,flexural strength,tensile modulus and tensile strain at break of the composites increase at first and then decrease,while the flexural modulus gradually decrease and the flexural strain at break gradually increase.When the amount of NDZ-201 is 0.7% and FG content is 70%,the tensile strength and bending strength of the composites reach 33.1 MPa and 52.3 MPa respectively,the thermal conductivity of the composites is 5.04 W·(m·K)^-1,which is 2℃ higher than that of the composites without NDZ-201.When the mass loss is 10%,the thermal decomposition temperature is increased by 2.86℃.