In this work, acrylates with various functionalities are employed as the branching coagent for improving the properties of long chain branched polylactide (LCB-PLA) induced by reactive extrusion with low content of cyclic organic peroxide (COP). It is discovered that the heat resistance and foaming performance of COP-initiated LCB-PLA are remarkably improved by the coagent. Specifically, the Vicat softening temperature and expansion ratio of 0.3 wt% COP-initiated LCB-PLA with 0.3 wt% coagent are sharply increased to above 150 °C and 27.0-fold, respectively (60 °C and 9.8-fold for 0.3 wt% COP modified PLA). This is due to the simultaneously enhanced melt strength and crystallization properties of LCB-PLA induced by the obviously enhanced branching degree by the coagent. Moreover, the branch-promotion efficiency of various coagents is found to be independent of the functionality due to the steric hindrance. The possible mechanisms on the formation of topological structures of COP modified PLA with coagents are proposed.

在这项工作中，具有各种功能的丙烯酸酯被用作支化助剂，以改善由低含量的环状有机过氧化物（COP）的反应性挤出诱导的长链支化聚丙交酯（LCB-PLA）的性能。发现通过助剂显着改善了COP引发的LCB-PLA的耐​​热性和发泡性能。具体而言，具有0.3 wt％助剂的0.3 wt％COP引发的LCB-PLA的维卡软化温度和膨胀率分别急剧增加至150°C和27.0倍以上（0.3 wt％时分别为60°C和9.8倍） COP修改的PLA）。这是由于助剂显着提高了支化度，从而同时提高了LCB-PLA的熔体强度和结晶性能。此外，由于空间位阻，发现各种助剂的分支促进效率与功能无关。提出了用助剂形成COP修饰的PLA拓扑结构的可能机理。