玻璃纤维增强煤基抗冲共聚聚丙烯的性能

采用双螺杆挤出共混法制备了短玻璃纤维(GF)改性聚丙烯(PP)2240S的共混物,通过力学性能分析测试、扫描电子显微镜表征、熔体流动速率测试和熔融结晶分析等研究了改性体系的力学性能、显微结构、加工流动性和结晶性能等。结果表明,当GF添加量为30%时,复合体系的弯曲强度、弯曲弹性模量、拉伸强度等较纯PP分别提高约112%,269%和108%,但GF与基体粘结力弱导致冲击强度没有提高;为进一步改善界面作用力,以5%马来酸酐接枝聚丙烯作相容剂,相同GF添加量下PP的弯曲强度达86.99 MPa,弯曲弹性模量达5073 MPa,拉伸强度达78.5 MPa,简支梁缺口冲击强度达14.78 kJ/m2,比纯PP的相关指标分别提高约161%,302%,190%和131%,GF与PP界面粘结力增强,PP的力学性能随GF含量的递增而大幅提高。但GF降低了PP的熔体流动速率,并且体系的结晶温度基本未变,结晶度降低,可能与未产生界面横晶有关。

Properties of Glass Fiber Reinforced Coal-Based Anti-Flushing Copolymerization Polypropylene

The mixture of short glass fiber modified polypropylene(PP)2240S was prepared by methods of blending in twin screw extruder.The mechanical properties,microstructure,processing fluidity and crystallization properties of the modified system were studied through mechanical analysis,surface electron microscope characterization,melt flow rate test and melt crystallization analysis.The results show that compared with pure PP,the flexural strength,flexural modulus,tensile strength of the composite system are increased by about 112%,269%and 108%respectively when the glass fiber is added to 30%,but the impact strength is not increased due to the weak bond force between the glass fiber and PP.In order to further improve the interface force,using 5%maleic anhydride grafted polypropylene(PP-g-MAH)as a phase tolerance agent,the PP flexural strength of the same glass fiber added amount reached 86.99 MPa,the flexural modulus reached 5073 MPa,the tensile strength reach 78.5 MPa,and the impact strength reach 14.78 kJ/m2,compared with the performance of pure PP,the flexural strength,flexural modulus,tensile strength and impact strength increased by about 161%,302%,190%and 131%respectively,and the adhesion force of glass fiber and PP interface increase.The mechanical properties of PP increase greatly with the increase of glass fiber content.While the glass fiber reduced the melting index of PP,and the crystal temperature of the system is basically unchanged,and the crystallinity is reduced,which might be related to the absence of interfacial transverse crystals.