Improving foamability of poly (lactic acid) (PLA) resin is a key issue for its critical foaming applications with high-performance and ultralow density. However, owing to the rheological nature of linear PLA chain structure with relatively low molecular weight, the overall foamability of PLA resin cannot meet the processing requirements of foaming purpose. Here, we describe a simple and versatile technique to prepare high foamability PLA resin by inducing chain extender through grafting octa(epoxycyclohexyl) polyhedral oligomeric silsesquioxanes (POSS) on carbon nanotubes (CNT). After the orderly assemble of the two nanoparticles, an obvious increase in melt elasticity of PLA is observed. The enhanced melt elasticity of PLA had a significant effect on controlling subsequent foaming behavior. Thus, a homogeneous and finer cellular morphology of PLA rigid foam was obtained with a proper content of CNT-POSS. Eventually, the expansion ratio of chain-extended PLA foam was 13 times higher than that of unmodified PLA foam. The proposed design methodology will potentially pave a way for designing and preparing high-performance PLA rigid foam products.

中文翻译：

---

碳纳米管接枝八环己基POSS延长PLA泡沫链的制备与表征

提高聚乳酸 (PLA) 树脂的发泡性是其高性能和超低密度的关键发泡应用的关键问题。然而，由于分子量相对较低的线性PLA链结构的流变性质，PLA树脂的整体发泡性不能满足发泡目的的加工要求。在这里，我们描述了一种简单而通用的技术，通过在碳纳米管 (CNT) 上接枝八（环氧环己基）多面体低聚倍半硅氧烷（POSS）来诱导扩链剂来制备高发泡性 PLA 树脂。两种纳米粒子有序组装后，PLA的熔体弹性明显增加。PLA 增强的熔体弹性对控制随后的发泡行为具有显着影响。因此，具有适当含量的 CNT-POSS 获得了 PLA 硬质泡沫的均匀和更精细的多孔形态。最终，扩链 PLA 泡沫的膨胀率比未改性 PLA 泡沫高 13 倍。所提出的设计方法可能为设计和制备高性能 PLA 硬质泡沫产品铺平道路。