摘要
采用溶液混合冷冻干燥法制备了质量分数0.004%的石墨烯/聚酰胺6(PA6)粒料,再用2种工艺制备石墨烯/PA6纤维——石墨烯/PA6粒料直接熔融纺丝;石墨烯/PA6粒料加入双螺杆挤出机熔融混合、挤出、造粒、熔融纺丝。用万能试验机测试了纤维的拉伸性能;用差示扫描量热分析测试了纤维的熔融行为并计算了结晶度;用扫描电镜(SEM)观察了石墨烯/PA6纤维的微观形态。研究结果表明,微量石墨烯的加入能够显著改善PA6纤维的拉伸性能,制备的石墨烯/PA6纤维的拉伸强度和拉伸模量分别可达到270 MPa和9.4GPa;工艺一制备的石墨烯/PA6纤维的热力学性能优于工艺二;较高的熔融纺丝温度可提高纤维的拉伸强度、拉伸模量、熔点和结晶度;SEM分析表明,石墨烯较均匀地分散在PA6基体中,纤维表面均匀,无明显瑕疵。
Solution mixing and freeze-drying method were used to prepare graphene/polyamide 6(PA 6)pellets with 0.004% graphene.Then,graphene/PA6 fibers were prepared by the following two processes respectively:one process is that graphene/PA6 pellets were directly used into melt spinning;the second process includes twin screw extrusion for the melting and remixing of graphene/PA6 pellets,granulation and melt spinning.Electronic universal testing machine was used to test the tensile properties of the graphene/PA6 fiber,DSC was used to analyze the melting behavior of graphene/PA6 fibers and calculate the crystallinity,and SEM was used to observe the morphology of graphene/PA6 fiber.Results show that the tensile properties of the fiber are improved by incorporating with a small amount of graphene,the tensile strength and modulus of the graphene/PA6 fiber could rise up to 270 MPa and 9.4 GPa respectively;graphene/PA6 fibers prepared by process one have better mechanical and thermodynamic performance than those prepared by process two;increasing the melt spinning temperature can improve the tensile strength,tensile modulus,melting point and crystallinity of the graphene/PA6 fibers;SEM images show that graphene is uniformly dispersed in the PA6 matrix and the surface of fiber does not present obvious defects.
引文
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