微孔发泡热塑性聚氨酯的形状记忆恢复特性

Shape-Memory-Recovery Characteristics of Microcellular Foamed Thermoplastic Polyurethane.

作者信息

Yun Chang-Seok, Sohn Joo Seong, Cha Sung Woon

机构信息

School of Mechanical Engineering, Yonsei University, 50, Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea.

出版信息

Polymers (Basel). 2020 Feb 6;12(2):351. doi: 10.3390/polym12020351.

DOI:10.3390/polym12020351

PMID:32041158

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7077500/

Abstract

We investigated the shape-recovery characteristics of thermoplastic polyurethane (TPU) with a microcellular foaming process (MCP). Additionally, we investigated the correlation between changes in the microstructure and the shape-recovery characteristics of the polymers. TPU was selected as the base material, and the shape-recovery characteristics were confirmed using a universal testing machine, by manufacturing dog-bone-type injection-molded specimens. TPUs are reticular polymers with both soft and hard segments. In this study, we investigated the shape-memory mechanism of foamed polymers by maximizing the shape-memory properties of these polymers through a physical foaming process. Toward this end, TPU specimens were prepared by varying the gas pressure, foaming temperature, and type of foaming gas in the batch MCP. The effects of internal structural changes were investigated. These experimental variables affected the microstructure and shape-recovery characteristics of the foamed polymer. The generated cell density changed, which affected the shape-recovery characteristics. In general, a higher cell density corresponded to a higher shape-recovery ratio.

摘要

我们采用微孔发泡工艺（MCP）研究了热塑性聚氨酯（TPU）的形状恢复特性。此外，我们还研究了聚合物微观结构变化与形状恢复特性之间的相关性。选择TPU作为基础材料，通过制造狗骨型注塑试样，使用万能试验机确认其形状恢复特性。TPU是具有软段和硬段的网状聚合物。在本研究中，我们通过物理发泡工艺使这些聚合物的形状记忆性能最大化，从而研究了发泡聚合物的形状记忆机制。为此，在间歇式MCP中通过改变气体压力、发泡温度和发泡气体类型来制备TPU试样。研究了内部结构变化的影响。这些实验变量影响了发泡聚合物的微观结构和形状恢复特性。产生的泡孔密度发生了变化，这影响了形状恢复特性。一般来说，泡孔密度越高，形状恢复率越高。