二氧化碳制备聚乳酸及其增韧体系微孔材料的研究  

Study on Microcellular Materials of PLA and Its Toughness System Prepared by CO_2

作　　者：王雷[1] 史学涛[1] 张广成[1] 张溢洋 马忠雷[1] 

机构地区：[1]西北工业大学理学院应用化学系,西安710129

出　　处：《工程塑料应用》2015年第10期59-65,共7页Engineering Plastics Application

基　　金：国家自然科学基金项目(51303149);西北工业大学中央高校基本科研业务费基础研究基金项目(3102014JCQ01095)

摘　　要：以CO2为物理发泡剂,采用间歇式升温发泡法制备了纯聚乳酸(PLA)发泡体系,质量分数为10%的丁二醇–己二酸–对苯二甲酸共聚酯(PBAT)增韧PLA发泡体系以及在此基础上添加1份硫酸盐类成核剂(LAK)后所制备的三元发泡体系,绘制了不同饱和压力下这3种体系的CO2解吸附曲线,研究了发泡工艺中CO2饱和压力以及解吸附时间对这3种体系泡孔结构的影响。结果表明,3种体系的CO2吸附率相当且解吸附曲线相似。随饱和压力的增大,3种体系泡孔尺寸均不同程度地减小,泡孔密度增大,尺寸分布趋于均匀。PBAT的加入减小了PLA的泡孔尺寸,增大了泡孔密度,在此基础上添加LAK可进一步改善PLA的泡孔结构,且在CO2的压缩条件(饱和压力为5 MPa)下,PBAT与LAK更能发挥其改善PLA泡孔结构的作用。随解吸附时间的增加,3种体系泡孔尺寸均不同程度地增大,泡孔密度减小,泡孔尺寸分布均匀性变差。在解吸附过程中,PLA/PBAT/LAK体系的泡孔尺寸始终最小,泡孔密度始终最大。Pure polylactide（PLA） foaming system, PLA foaming system toughened by butylene glycol-adipic acid-tenary terephthalate polyester （PBAT） with mass fraction of 10% and their ternary foaming system by further adding 1 phr sulphate nucleating agent （LAK） were prepared by batch heating foaming process through taking carbon dioxide （CO2） as physical foaming agent. The CO2 desorption curves of the three systems under different saturation pressure were drew, the influences of saturation pressure and desorption time in foaming process on the cell structures of the three systems were investigated. The results show that the three systems have similar CO2 adsorption rate and desorption curve. With increasing saturation pressure, the cell sizes of the three systems are reduced and their distributions tend to be uniform, meanwhile, the cell densities increase. The addition of PBAT decreases the cell size of PLA and increases the cell density, on this basis, adding LAK can further improve the cell structure, moreover, under compressed CO2 （saturation pressure is 5 MPa）, PBAT and LAK can improve the cell structure much more than that under supercritical CO2. With the increase of the desorption time, the cell sizes of the three systems increase and the cell densities decrease, meanwhile, the distribution homogeneity of the cell sizes becomes worse. During the desorption process, the cell size of PLA / PBAT / LAK system is the smallest with the maximum cell density compared with PLA and PLA / PBAT system.

关 键 词：聚乳酸 增韧 解吸附 饱和压力 泡孔结构 

分 类 号：TQ311[化学工程—高聚物工业]