中文摘要：

通过苯乙烯-丙烯腈共聚物（SAN）共混改性聚氯乙烯（PVC），制备了PVC／SAN共混材料。利用转矩流变、色差分析、表面形貌分析、元素分析等方法研究了PVC／SAN共混材料的加工性能和抗紫外老化性能。结果表明，SAN的加入可促进PVC的塑化，改善其加工性能；同时SAN具有较强的紫外光吸收能力，能抑制PVC脱氯化氢，显著降低紫外老化时PVC颜色变暗、变红和变黄的速率；此外SAN的引入使PVC／SAN共混材料表面平整、致密，可以有效阻止紫外光和氧气深入到材料内部造成严重的破坏，从而显著提高PVC的抗紫外老化性能。

英文摘要：

Styrene-acrylonitrile copolymer（SAN） was used to modify poly（vinyl chloride）（PVC）, and PVC/SAN blends were obtained. Then processability and anti ultraviolet aging performance of PVC/SAN blends were studied by torque rheometer, chromatic aberration, SEM, and X-ray photoelectron spectroscopy（XPS）. It is found that adding SAN can decrease the plasticizing time of PVC, indicating that the processability of PVC is improved. Meanwhile, SAN has strong ultraviolet absorption ability, and dehydrochlorination reaction of PVC is inhibited. As a result, PVC/SAN blends has high color stability when aged under ultraviolet light. In addition, surface of PVC/ SAN blends is smooth and dense, leading to limitation of the ultraviolet light and oxygen penetrating inside the material. Therefore, anti ultraviolet aging performance of PVC is significantly improved by addition of SAN.