碳纤维/聚乳酸复合材料的结晶性能和流变特性

摘要

Carbon fiber/poly(lactic acid)(CF/PLA)composites were prepared by using CF as filler.The mass ra-tio of CF(CF∶PLA)were 1%,3%,5%,10% and 15%.Crystallinity and rheological properties of PLA and CF/PLA composites were investigated.The results show that,CF/PLA composites with 1% and 3% CF can improve the overall crystallinity of PLA at cooling process due to the heterogeneous nucleation mechanism.The intensity of XRD diffraction peaks gets stronger.The crystallization temperature and crystallinity respectively of CF/PLA com-posites increase to 112.5℃ and 30.7%.And the rheological properties are similar to those of pure PLA.When the mass ratio of CF increases to 5%,which is the "percolation threshold",the viscosity of CF/PLA composites gets a sharp rise.The movements of molecular segments are limited,leading a decrease in crystallinity of PLA.When the mass ratio of CF is 15%,the crystallization temperature of CF/PLA composites reduces to 93.1℃ and the crystal-linity is only 2.5%.%以碳纤维(CF)作填料,制备了CF/聚乳酸(CF/PLA)复合材料,CF的质量比(CF∶PLA)为 1%、3%、5%、10%和 15%.研究了PLA及CF/PLA复合材料的结晶性能和流变特性.结果表明,质量比≤3%时,CF在基体中起到了异相成核的作用,提高了PLA的结晶性能,XRD衍射峰强度增强,CF/PLA 复合材料结晶温度和结晶度分别提高到112.5℃和30.7%,流变特性与纯PLA相似.CF的质量比增加到5%时,达到"渗流阈值",黏度激增,限制了分子链段的自由运动,导致CF/PLA复合材料结晶性能下降.CF质量比为15%时,CF/PLA复合材料结晶温度降低至93.1℃,结晶度只有2.5 %.