碳纤维/聚乳酸复合材料的结晶性能和流变特性
Crystallization and rheological properties of carbon fiber/poly (lactic acid) composites

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%。 Carbon fiber/poly (lactic acid) (CF/PLA) composites were prepared by using CF as filler. The mass ratio 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 composites 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 crystallinity is only 2.5%. 太原工业学院青年科学基金（2016LQ12）；太原工业学院大学生创新创业训练项目（GK20170097）