GE/AlN/CO-PA导热复合材料的制备与性能研究

Study on Properties of GE/AlN/CO-PA Thermal Conductive Composites and Its Preparation

以石墨烯（GE）和氮化铝（Al N）为导热填料,以硅烷偶联剂KH-550为表面改性剂,通过溶液共混法制备导热填料/三元共聚聚酰胺（CO-PA）导热复合材料,制备了Al N/CO-PA和GE/Al N/CO-PA复合材料。XRD和SEM分析表明,GE、Al N能够改变聚酰胺的结晶晶型;DSC分析表明导热填料能够改善导热复合材料结晶性能;TGA分析表明导热填料能够提高导热复合材料的热稳定性,当Al N含量为50%,Al N/CO-PA导热复合材料的75%损失温度T75%和Td,max分别比纯CO-PA高28.33℃和20℃;Al N含量为50%、GE含量为2%时,GE/Al N/CO-PA导热复合材料的T75%和Td,max分别比纯CO-PA高30℃和20.3℃;在Al N含量为50%、GE含量为8%时,复合材料的热导率为2.345 W/（m·K）,是纯CO-PA热导率的9.1倍;随着温度的升高,CO-PA和导热复合材料的热扩散率逐渐降低;力学测试表明低含量的导热填料能够提高复合材料的力学性能,在Al N含量为10%时,复合材料的拉伸强度从38 MPa增加到75.73 MPa,屈服强度从19.8 MPa提高到54.23 MPa。

A thermal conductive filler/CO-PA thermal conductive composite material was prepared by solution blending method using graphene（GE）and aluminum nitride（Al N）as thermal conductive filler and silane coupling agent KH-550 as surface modifier,and Al N/CO-PA and GE/Al N/CO-PA composite materials were prepared.The results of XRD and SEM analysis show that the addition of GE and Al N can change the crystal form of nylon;DSC analysis shows that GE and Al N can improve the crystallinity of thermally conductive composites;TGA analysis shows that when the content of Al N is 50%,the T75% and Td,max of the thermally conductive composite are28.33℃and 20℃higher than those of CO-PA,respectively;when the content of Al N is 50%and the content of GE is 2%,the T75% and Td,max of the thermally conductive composite are 30℃and20.3℃higher than those of CO-PA,respectively;when the content of Al N is 50%and the amount of GE is 8%,the thermal conductivity of the composite is 2.345 W/（m·K）,which is 9.1 times of the thermal conductivity of pure CO-PA.With the increase of temperature,the thermal diffusivity of CO-PA and thermal conductivity composites decrease gradually;and the specific heat capacity of CO-PA and thermal conductive composites increase.The mechanical tests show that when the content of Al N is 10%,the tensile strength of the composites increases from 38 MPa to 75.73MPa and the yield strength increases from 19.8 MPa to 54.23 MPa.