Instituto de Ciencia y Tecnología de Polímeros, ICTP-CSIC, c/Juan de la Cierva, 3, 28006, Madrid, Spain.
J Phys Chem B. 2011 Sep 22;115(37):10836-43. doi: 10.1021/jp2058194. Epub 2011 Aug 29.
The dynamic crystallization and melting behavior of isotactic polypropylene-tungsten disulfide (iPP/IF-WS(2)) nanocomposites incorporating a β-nucleating agent is investigated by X-ray diffraction and differential scanning calorimetry. A conventional melt-processing strategy is employed to generate new materials that exhibit variable α and β polymorphism under the appropriate kinetic conditions. The results show that when the dual additive system is employed the nucleation ability on isotactic polypropylene not only depends on the nucleation efficiency (NE) and relative content of the individual α and β-nucleating agents, but also on the cooling rates employed. The nucleating behavior of the additives is explained by competitive nucleation, and the correlation between crystallization and melting temperatures and relative content of α and β-crystals of iPP in the nanocomposites is discussed.
采用 X 射线衍射和差示扫描量热法研究了含有β成核剂的间规聚丙烯-二硫化钨（iPP/IF-WS(2)）纳米复合材料的动态结晶和熔融行为。采用常规熔融加工策略生成新材料，在适当的动力学条件下，新材料表现出可变的α和β多态性。结果表明，当采用双添加剂体系时，对间规聚丙烯的成核能力不仅取决于成核效率（NE）和单个α和β成核剂的相对含量，还取决于所采用的冷却速率。添加剂的成核行为可以用竞争成核来解释，并讨论了纳米复合材料中 iPP 的结晶和熔融温度以及α和β晶体的相对含量之间的相关性。
