成核母粒及螺杆组合对玻纤增强PET复合材料性能的影响

Effect of Nucleating Masterbatch and Screw Combination on the Properties of Glass Fiber Reinforced PET Composites

采用熔融插层法制备了一种高效成核母粒,研究了该成核母粒对玻璃纤维(GF)增强聚对苯二甲酸乙二醇酯(PET)复合材料性能的影响。结果表明,加入6%(质量分数,下同)的成核母粒时,GF增强PET复合材料的起始结晶温度比纯PET高24.8℃,结晶温度范围比纯PET扩大了66.3℃,冷结晶峰基本消失,可在70℃的模温下进行注射成型;同时探讨了螺杆组合对GF增强PET复合材料性能的影响,结果表明,螺杆前段的剪切太强会降低复合材料的冲击强度,通过优化螺杆组合,制备出综合性能优异的GF增强PET复合材料,其热变形温度为228℃,拉伸强度159 MPa,弯曲强度235 MPa,冲击强度101 J/m。

High effective nucleating masterbatch was prepared by melt intercalation approach, and its effect on the properties of glass fiber reinforced PET composites was investigated. When the content of nucleating masterbatch was 6 wt %, the initiative crystallization temperature and crystallization range of the composite increased 24.8 ℃ and 66.3 ℃ compared to the neat PET, respectively. The addition of masterbatch essentially diminished the cooling crystallization and made it possible for the molding carried out at a mold temperature of 70℃. The effect of screw combination on the properties of glass fiber reinforced PET composites was also studied. It was found that if the shearing stress was too high, the impact strength of the composites would decline. Based on the optimized screw combination, the glass fiber reinforced PET composites with excellent comprehensive properties were prepared; the heat distortion temperature reached 228 ℃, and the tensile, flexural, and impact strengths obtained were 159 MPa, 235 MPa, and 101 J/m, respectively.