长支链对原位反应共混制备增韧聚乳酸性能影响  

Effect of Branched Long Chain on Properties of Super Tough Polylactide Prepared by In Situ Reactive Blending

作　　者：李爽 纪小宾 张紫妮 刘凤谨 白静 LI Shuang;JI Xiaobin;ZHANG Zini;LIU Fengjin;BAI Jing(Shenzhen Polytechnic,Shenzhen,Guangdong 518055,China;Heze Vocational College,Heze,Shandong 274000,China;Sunsong(Shenzhen)Polymer Eco-Friendly New Material Co.,Ltd.,Shenzhen,Guangdong 518000,China)

机构地区：[1]深圳职业技术学院,广东深圳518055 [2]菏泽职业技术学院,山东菏泽274000 [3]深圳市三上高分子环保新材料股份有限公司,广东深圳518000

出　　处：《塑料》2022年第4期98-102,124,共6页Plastics

基　　金：深圳基础研究项目(JCYJ20170818114324998);广东省基础与应用基础研究基金(2020A1515011545);江门市功能材料与涂料重点实验室(江科[2018]352号);广东省绿色高性能新材料研发工程技术研究中心(江科[2019]131号);深圳职业技术学院2021年“创新工程”项目(CXGC2021C0004)。

摘　　要：通过伽马射线辐照法制备了不同长链支化含量的长链支化聚乳酸(LCB-PLA),长支链有效地提高了聚乳酸(PLA)的熔体强度。通过将LCB-PLA与聚乙二醇二丙烯酸酯(PEGDA)单体反应共混,制备了LCB-PLA与交联PEGDA的共混物(LCB-PLA/CPEGDA)。研究发现,交联的PEGDA与PLA体系发生明显相分离,呈现双连续相结构。流变学研究发现,LCB-PLA/CPEGDA共混物中存在网络结构,共混物的弹性响应增强,剪切变稀明显且分子链松弛变缓。差示扫描量热仪(DSC)测试结果表明,PEGDA降低了共混物的玻璃化转变温度,提高了PLA的结晶能力。力学性能研究发现,LCB-PLA/CPEGDA共混物整体比PLA/CPEGDA共混物表现出更好的韧性和缺口冲击强度。LCB-PLA/CPEGDA共混物中,最高的断裂伸长率为259%,约是纯聚乳酸的44倍;最高的缺口冲击强度为69 kJ/m^(2),约是PLA的36倍。Long chain branched polylactide(LCB-PLA) with different branching degrees were prepared by using gamma ray irradiation. It was found that branched long chain effectively had improved melt strength of PLA. LCB-PLA and cross-linked poly(ethylene glycol) diacrylate(CPEGDA) blends were prepared by reactive blending of LCB-PLA and PEGDA monomer. It was found that cross-linked PEGDA and PLA system had showed phase separation dramatically and form bicontinuous phase structure.The study of rheology founded that LCB-PLA/CPEGDA blends existed network structure and showed higher melt strength, stronger shear thinning tendencies and slower chain relaxes. Differential scanning calorimetry(DSC) found that the addition of PEGDA decreased the glass transition temperature of blends and improved crystalline ability of PLA. The study of mechanical properties found that LCB-PLA/CPEGDA blends showed better tensile toughness and notched impact strength. The highest elongation at break was 259%, which was about 44 times of PLA,while the highest notched impact strength was 69 kJ/m^(2), which was about 36 times of PLA.

关 键 词：长支链 聚乳酸 聚乙二醇二丙烯酸酯 流变 增韧 

分 类 号：TQ323.4[化学工程—合成树脂塑料工业]