Abstract

The aim of this study was to produce crosslinked low-density polyethylene (LDPE) composites using peroxide and octavinyl polyhedral oligomeric silsesquioxane (OvPOSS) and to examine the shape memory behavior. The strategy was to use OvPOSS as a coagent to increase the crosslinking density and crosslinking efficiency while improving the mechanical and shape memory properties as well. The peroxide concentration, from 0.5 phr to 3.0 phr, was taken as the experimental parameter, with 4 phr OvPOSS added to all composites. The melt mixing route was applied similar to that which would be used industrially. The thermo-responsive shape memory properties near the melting point were examined in tension mode. The dispersion of OvPOSS in the LDPE matrix was observed via scanning electron microscopy and Si-mapping. In addition, the thermal, mechanical, structural, and rheological features of the novel LDPE/OvPOSS and LDPE/peroxide/OvPOSS systems were investigated. It was observed that the crosslinking density of LDPE increased in the presence of OvPOSS, which affected the mechanical, rheological and thermal properties and increased the shape recovery ratio of the LDPE.

摘要

本研究的目的是使用过氧化物和八乙烯基多面体低聚倍半硅氧烷 (OvPOSS) 生产交联低密度聚乙烯 (LDPE) 复合材料，并检查形状记忆行为。该策略是使用 OvPOSS 作为助剂来提高交联密度和交联效率，同时改善机械和形状记忆性能。将 0.5 phr 至 3.0 phr 的过氧化物浓度作为实验参数，将 4 phr OvPOSS 添加到所有复合材料中。熔体混合路线的应用类似于工业上使用的路线。在张力模式下检查了熔点附近的热响应形状记忆特性。OvPOSS 在 LDPE 基体中的分散情况通过扫描电子显微镜和 Si-mapping 进行观察。此外，热、机械、研究了新型 LDPE/OvPOSS 和 LDPE/过氧化物/OvPOSS 系统的结构和流变特性。观察到在 OvPOSS 存在下 LDPE 的交联密度增加，这影响了 LDPE 的机械、流变和热性能并增加了 LDPE 的形状恢复率。