二氧化碳气体制备层状聚苯乙烯发泡材料

Preparation of Layered Foam Morphology Polystyrene Using Compressed Carbon Dioxide

将珠状和粒状聚苯乙烯(PS)样品模压后在高压CO2条件下饱和,采取快速升温法制备了结构新颖的层状发泡材料.通过扫描电子显微镜(SEM)以及不同饱和条件下CO2在PS中溶解度的分析,初步研究了区域性弱链段缠结力对气体成核、泡孔形态、泡孔尺寸和分布的影响.结果表明珠状PS在压制成型过程中其珠粒界面链段相互作用力较弱.由于基体中界面区域链段的缠结能力不同,在不同区域CO2气体的成核和增长也不同,通过控制发泡的过程参数,可以得到独特的PS层状泡孔形态.

The sample prepared by compression molding polystyrene（PS） beads and pellets was saturated in compressed carbon dioxide（CO2）.After reaching equilibrium,the sample was foamed by temperature soaking method.Intriguing layered foam morphology was obtained.The effect of weak chain entanglements on the bubble nucleation,cell morphology,cell size and distribution were investigated by scanning electron microscopy（SEM） and the solubility measurement of CO2 in PS.The results indicated that the weak entan-glements of chains were introduced into the interfaces between the beads in bead PS during the compression molding process.Due to the different chain entanglement ability in the matrix,the bubble growth and nu-cleation of CO2 gas in different regions were not the same.By controlling the parameters of foaming proc-ess,unique and novel structures with layered foams were generated.