用挤出 -拉伸 -注塑法制备了PP/PA66原位复合材料 ,研究了拉伸比 (λ)和增容剂用量 (Cg)对PA66成纤性和材料力学性能的影响。结果表明 :增大λ有利于成纤 ,能明显提高材料的冲击强度 (αk) ,拉伸强度 (σt)也有增益 ;增加Cg 不利于成纤 ,导致αk 下降 ,但能改善界面粘结而使σt 明显提高 ;材料σt 和αk 分别主要受界面结构和纤维形态控制 ,决定了它们随λ和Cg 的变化规律 The PP / PA66 in-situ composites were prepared by extrusion-stretch-injection molding. The effect of stretch ratio (λ) and amount of compatibilizer (Cg) on ​​the PA66 fiber formation and mechanical properties were investigated. The results show that: increasing λ is good for fiber forming, the impact strength (αk) and the tensile strength (σt) of the material are also increased obviously. Increasing Cg is unfavorable to fiber forming, resulting in the decrease of αk, σt significantly increased; σt and αk materials were mainly controlled by the interface structure and fiber morphology, which determines their variation with λ and Cg