中文摘要：

采用硅烷偶联剂（KH-550）对硫酸钙晶须进行表面改性,对改性前后硫酸钙晶须的结构进行了红外光谱表征,运用差示扫描量热仪研究了β成核剂（TMB-5）、改性后的硫酸钙晶须（K-CSW）及K-CSW/TMB-5复合成核剂改性聚丙烯（PP）的结晶和熔融行为,并着重研究了K-CSW与TMB-5在PP中的协同成核改性效果。结果表明,硅烷偶联剂已成功偶联于硫酸钙晶须的表面,K-CSW可有效促进PPβ晶型的形成,且K-CSW与TMB-5在PP中具有明显的协同成核效果,对PP结晶峰温度和β晶成核能力的提升也更加显著;当PP中TMB-5添加量为0.2%（质量分数,下同）、KCSW添加量为2%时,改性后PP中β晶的相对含量高达90.1%,结晶峰温度从纯PP的122.3℃升高至127.2℃。

英文摘要：

A surface modification of calcium sulfate whiskers was performed by using a KH-550 silane coupling agent,and their structures before and after the surface modification were investigated comparatively by Fourier-transform infrared spectroscopy.The crystallization and melting behaviors of polypropylene（PP）nucleated withβ-nucleating agent（TMB-5）,surfacemodified CaSO4 whiskers（K-CSW）,and a mixture of CaSO4 whiskers and TMB-5were studied by differential scanning calorimetry,and the nucleating effects of these three nucleating agents were compared.The results indicated that the K-CSW could effectively promote the formation ofβ-crystals and it also exhibited a synergistic nucleating effect with TMB-5,thus resulting in an improvement in crystallinity of PP.When 0.2 wt % of TMB-5and 2 wt % of K-CSW were incorporated into PP,the relative content ofβ-crystals in PP reached 90.1 %,and the peak crystallization temperature of nucleated PP increased to 127.2 ℃from 122.3 ℃ of pure PP.