不同PEG含量对PLA/PEG共混物结晶动力学的影响  

Effect of Different Poly(ethylene glycol)Contents on Crystallization Kinetics of Polylactide/Poly(ethylene glycol)Blends

作　　者：白静 崔晶 顾玉蓉 刘红波[1] BAI Jing;CUI Jing;GU Yurong;LIU Hongbo(Shenzhen Polytechnic,Shenzhen,Guangdong 518000,China)

机构地区：[1]深圳职业技术学院,广东深圳518000

出　　处：《塑料》2020年第2期64-68,共5页Plastics

基　　金：深圳基础研究项目(JCYJ20170818114324998);深职院[2018]26号(601822K24023)。

摘　　要：采用溶液共混法制备了一系列不同配比的聚乳酸(PLA)/聚乙二醇(PEG)共混物。通过偏光显微镜(POM)、扫描电镜(SEM)和差式扫描量热仪(DSC)研究了不同PEG含量的PLA/PEG共混物在不同结晶温度下,聚乳酸的晶体形貌、球晶生长速率及热力学性能。研究发现,PEG能够显著提高聚乳酸球晶的生长速率。当PEG含量为60%时,PLA/PEG共混物中聚乳酸球晶的生长速率最快,达到23.6μm/min,比纯聚乳酸的最快球晶生长速率(0.5μm/min)高47倍。但是,当PEG含量高于60%时,聚乳酸球晶的生长速率有所降低。同时,PLA/PEG共混物中聚乳酸球晶速率随结晶温度变化的取向,均向低温移动。另外,PLA/PEG共混物中聚乳酸球晶呈现环状花纹。DSC测试结果表明,随着PEG含量的增加,PLA/PEG共混物的玻璃化转变温度明显降低。A series of polylactide/poly(ethylene glycol)(PLA/PEG)blends with different PEG contents were prepared by using solution blending method.The morphology,growth rate and thermal property of spherulites for polylactide in PLA/PEG blends with different PEG contents during isothermal crystallization at various temperatures were studied by using polarized optical microscopy(POM),scanning electron microscope(SEM)and differential scanning calorimetry(DSC).The results showed that PEG could accelerate the growth rate of PLA spherulite dramatically.The growth rate of PLA spherulite in PLA/PEG(40/60)blends was the fastest of all with 23.6 mm/min,which is about 47 times of neat PLA with 0.5 mm/min.However,when the PEG content was above 60%,the growth rate of PLA spherulite in PLA/PEG blends reduced.Meanwhile,the temperature for the measurable nucleation and spherulitic growth of PLA in PLA/PEG blends could be eventually pushed down close to the glass transition temperature of neat PLA.In addition,PLA spherulities in PLA/PEG blends showed ringbanded texture.DSC results showed that glass transition temperature of PLA/PEG blends reduced as the increase of PEG content.

关 键 词：聚乳酸 聚乙二醇 结晶 动力学 球晶 

分 类 号：TQ323.4[化学工程—合成树脂塑料工业]