The development of a reactively processed polypropylene nanocomposite (PPNC) with consequential improvements in the heat deflection temperature (HDT), Vicat softening temperature (VST), and crystallization peak temperature (T_c) is reported herein. Neat PP without nanoclay was also reactively processed to elucidate the effects of fillers on the improvement in physical properties. The results show a considerable improvement in the HDT of PPNC (77.9 °C) compared to those of neat PP (62.6 °C) and reactively processed branched PP (BPP; 69.2 °C). Moreover, the T_c of PP in PPNC improved by ~14% compared to that of neat PP. Various models of nonisothermal crystallization kinetics were employed to elucidate the nucleation and crystal growth mechanisms, and to correlate them with the observed HDT improvement in PPNC. Thermal transitions investigated by modulated differential scanning calorimetry explained the changes observed in the VSTs of all the samples. To the best of our knowledge, this is the first report on a significant improvement in HDT along with a marked increase in Tc. Such simultaneous improvements in HDT, VST, and T_c are highly desirable for applications involving the use of PP‐based materials in rigid packaging.

中文翻译：

---

成核和生长机理对反应加工聚丙烯纳米复合材料热变形温度的影响

本文报道了在热变形温度（HDT），维卡软化温度（VST）和结晶峰温度（T _c）方面得到相应改善的反应性加工的聚丙烯纳米复合材料（PPNC）的开发。还对不含纳米粘土的纯PP进行了反应性处理，以阐明填料对改善物理性能的影响。结果表明，与纯PP（62.6°C）和反应处理的支链PP（BPP; 69.2°C）相比，PPNC的HDT（77.9°C）有了显着提高。而且，T _c与纯PP相比，PPNC中PP的含量提高了约14％。使用各种非等温结晶动力学模型来阐明成核和晶体生长机理，并将它们与PPNC中观察到的HDT改善联系起来。通过调制差示扫描量热法研究的热转变解释了所有样品的VST中观察到的变化。据我们所知，这是关于HDT显着改善以及Tc显着增加的第一份报告。对于硬质包装中使用基于PP的材料的应用，HDT，VST和T _c的这种同时改进是非常理想的。