超临界CO_2微孔发泡制备聚乳酸/磷酸三钙多孔材料

利用超临界二氧化碳(sc-CO2)微孔发泡方法制备聚乳酸/磷酸钙(PLA/TCP)多孔材料,通过扫描电子显微镜(SEM)观察TCP颗粒分散和泡孔形态。结果表明,TCP质量分数为1 wt%和3 wt%时,微米级TCP颗粒均匀分布在PLA基体中,在发泡过程中起到异相成核的作用,减小泡孔尺寸同时增加泡孔密度。当TCP含量为5 wt%时,TCP颗粒出现团聚,异相成核作用减弱,泡孔密度下降。随着发泡温度升高,泡孔尺寸增大的同时泡孔壁变薄甚至破裂,发泡温度对泡孔密度影响不大。增加发泡压力,泡孔的数量急剧增加,同时泡孔的尺寸减少,泡孔壁变厚。

Supercritical CO2 Microcellular Foaming Preparation of Polylactic Acid/Tricalcium Phosphate Porous Materials

Using supercritical CO2 microcellular foaming method preparation of polylactic acid/calcium phosphate （PLA/TCP） porous materials, by scanning electron microscope （SEM） to observe the TCP particle dispersion and bubble hole form. Results show that TCP mass fraction of 1 wt % and 3 wt %, micron grade TCP particles uniformly distributed in the PLA matrix, play the role of heterogeneous nucleation in the process of foam, bubble hole density to decrease the size of the bubble hole at the same time increases. When TCP content is 5 wt%, TCP particles appear together, heterogeneous nucleation effect is abate, bubble hole density decreased. As the foaming temperature, bubble hole size and at the same time bubble hole wall thinning even burst, foaming temperature on bubble hole density had little impact. Increases pressure fnam, bubble is a sharp increase in the number of holes the size of the bubble hole to reduce at the same time, the hole wall.