超临界二氧化碳制备热塑性聚氨酯弹性体发泡材料的发泡机理和性能研究

摘要

Expanded thermoplastic polyurethane (E-TPU)was prepared by supercritical carbon dioxide and the foaming mechanism and properties were studied.The results showed that,the pressure release rate and foaming temperature were the two important factors affecting the foaming properties of E-TPU.As the pressure release rate increased,the nucleation rate and amount were improved.As the foaming temperature increased,the bubbles expanded and grew up easily,and the density decreased.But when the temperature was too high,the bubbles ruptured and collapsed,and the density increased.When foaming temperature was about 130 C,the density of E-TPU was the smallest and the foaming properties were the best.%用超临界二氧化碳制备热塑性聚氨酯弹性体发泡材料(E-TPU),分析发泡机理并研究发泡性能.结果表明:泄压速率和发泡温度是影响E-TPU发泡性能的两个重要因素;增大泄压速率有利于提高气泡成核速率和成核数量;升高发泡温度使气泡易膨胀长大,E-TPU密度减小;但发泡温度过高会导致气泡破裂和塌陷,E-TPU密度增大;当发泡温度为130℃左右时,E-TPU密度最小,发泡性能最好.