摘要
应用超临界CO2制备微孔聚乳酸,研究发泡条件和结晶度对微孔形貌的影响。结果表明,固定饱和压力与降压速率,升高温度有利于泡孔的生成;超过聚乳酸(PLA)完全熔融温度,无法生成泡孔;固定发泡温度与降压速率,提高压力有与温度类似的作用;由于PLA较低的熔体强度,降压速率的提高增大了生成泡孔之间的竞争,可形成孔道连通的微孔形貌;而PLA本身的结晶度很大程度上影响了PLA可发泡的区间,结晶不利于发泡。
The cell morphology of the microcellular polylactide acid（PLA）prepared by supercritical carbon dioxide was studied.According to the results,as the temperature increases close to completed melt temperature at a given saturation pressure and depressurization rate,the cell developed well.The effect of increased saturation pressure is similar to increased temperature.Due to the low melt strength of PLA,as increased depressurization rate,the competition between cells is reinforce and interconnected cell morphology is formed;the crystallinity of PLA restricts the range of foaming and blocks the development of cells.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2010年第3期138-141,共4页
Polymer Materials Science & Engineering
基金
国家自然科学基金重大项目(20490204)
国家自然科学基金青年基金项目(50703011)
关键词
聚乳酸
微孔材料
超临界CO2
polylactide acid
microcellular
supercritical carbon dioxide
