超临界CO_2液相插层法制备PP/石墨烯复合材料

Preparation of Polypropylene/Graphene Composites by Supercritical CO_2 Liquid Phase Intercalation

石墨烯具有优异的性能,用其对聚合物材料进行改性可以得到高性能的聚合物基复合材料。石墨烯在聚合物基体中的分散性已成研究重点。为此,根据熔融复合法,以超临界CO_2为辅助插层剂,对石墨烯进行剥离、分散,制备出性能良好的聚丙烯(PP)/石墨烯复合材料。研究了超临界CO_2浸润剥离对其热稳定性、力学性能的影响。结果表明,石墨烯的加入和超临界CO_2浸润剥离均使PP的热稳定性有所升高。当石墨烯的质量分数为10%时,PP达到最大热失重速率时的温度从459.6℃提高到466.7℃,而且通过液相插层技术,超临界CO_2浸润、剥离石墨烯,可使其在PP基体中分散性更好;超临界CO_2浸润过的PP/石墨烯复合材料的拉伸强度和弯曲强度都有所提升,其拉伸强度和弯曲强度分别为35.82 MPa和40.75MPa,相比于常规的PP/石墨烯复合材料分别提高了8.4%和25.4%;缺口冲击强度有略微降低,浸润过的PP/石墨烯复合材料的缺口冲击强度达到7.20kJ/m^2。相比于常规的PP/石墨烯复合材料降低了10.4%。

Graphene has excellent properties.It can be used to modify polymer materials to obtain high performance polymerbased composite materials,so that the composite materials have high conductivity,high strength,high thermal stability,etc.The dispersibility of graphene in polymer matrix has become a research focus.According to the melting and recombination method,the graphene was stripped and dispersed with supercritical CO2 as the auxiliary intercaler,and the polypropylene(PP)/graphene composites with good performance were prepared.The effects of supercritical CO2 immersion stripping on thermal stability and mechanical properties were studied.The results show that the thermal stability of PP increases with the addition of graphene and the supercritical CO2 infiltration and stripping.When the mass fraction of graphene is 10%,polypropylene thermal weight loss rate of maximum temperature is from 459.6℃to 466.7℃.By using liquid phase intercalation technology,supercritical CO2 infiltrating and stripping graphene can make it more dispersed in PP matrix.The tensile strength and flexural strength of PP/graphene composites soak with supercritical CO2 were both improved,and their tensile strength and flexural strength are 35.82 MPa and 40.75 MPa respectively.Compared with conventional PP/graphene composites,the flexural strength and tensile strength are increased by 8.4%and 25.4%respectively.The notch impact strength is slightly reduced,and the notch impact strength of the impregnated PP/graphene composite reach 7.20 kJ/m2.Compared with conventional PP/graphene composites,the reduction is 10.4%.