六方氮化硼填充聚丙烯复合材料的力学性能

Mechanical Properties of the Composites of Polypropylene Filled with Hexagonal Boron Nitride

为了确认在聚丙烯(PP)中填充六方氮化硼(hBN)对PP/hBN复合材料力学性能的影响,采用双螺杆熔融共混经挤出或注塑制备了PP/hBN复合材料。随着hBN质量分数的增加,PP/hBN复合材料的拉伸强度和断裂伸长率不断降低。但是,随着hBN质量分数的增加,PP/hBN的抗冲击强度、弯曲强度、拉伸模量和弯曲模量提高,当hBN质量分数为20%时,冲击强度达到2.73 kJ/m^(2),拉伸模量达到430 MPa;当hBN质量分数为25%时,弯曲强度达到38.31 MPa,弯曲模量达到1420.73 MPa。hBN能明显提高PP结晶成核的数量和结晶速率,随着hBN质量分数的增加,PP/hBN复合材料的结晶度总体呈现出降低趋势,热稳定性有所提高。

In order to further confirm the effect of hexagonal boron nitride(hBN)mass fraction on mechanical properties of polypropylene(PP),PP composites filled with hBN were prepared by twin-screw melt blending through extrusion or injection molding.The tensile strength and elongation at break of the PP/hBN composites decreased continuously with the increase of hBN mass fraction.However,the impact strength,flexural strength,tensile modulus and flexural modulus increased with the increase of hBN mass fraction.When the mass fraction of hBN is 20%,the impact strength reaches 2.73 kJ/m^(2) and the tensile modulus is 430 MPa.When the mass fraction of hBN is 25%,the flexural strength is 38.31 MPa and the flexural modulus is 1420.73 MPa.The number of nucleation and crystallization rate are increased for PP filled with hBN,however,with the increase of hBN mass fraction,the crystallinity of PP/hBN composites decreases and the thermal stability is improved.