PLLA/PDBI共混薄膜的热学、力学及阻隔性能研究  

Thermal,mechanical and barrier properties of PLLA/PDBI blend films

作　　者：任思颖 杜佳慧 孙滔 吴怡锋 郭久实 云雪艳 REN Siying;DU Jiahui;SUN Tao;WU Yifeng;GUO Jiushi;YUN Xueyan(College of Food Science and Engineering,Inner Mongolia Agricultural University,Hohhot 010018,China)

机构地区：[1]内蒙古农业大学食品科学与工程学院,呼和浩特010018

出　　处：《中国塑料》2024年第12期60-65,共6页China Plastics

基　　金：国家自然科学基金资助项目(21965026、52163012);内蒙古自治区科技计划(2021GG0337);内蒙古自治区青年科技人才发展项目(创新团队NMGIRT2310)。

摘　　要：将聚(衣康酸丁二醇酯)共聚物(PBI)引入到聚(D-乳酸)(PDLA)主链中,合成出聚(D-乳酸-衣康酸丁二酯)共聚物——PDBI,将聚(L-乳酸)(PLLA)和PDBI共混制备成不同比例的PLLA/PDBI薄膜。结果表明,随着共混比例的增加,总结晶度(Xtotal)呈现先增长后下降趋势,PLLA/50%PDBI形成的立构复合结晶(SC结晶)最多,其Xtotal可达到9.12%,熔点高达205℃,热学性能大大提高;断裂伸长率呈先增加后减少的趋势,拉伸强度和弹性模量都呈现出先降低再升高的趋势,PLLA/50%PDBI的断裂伸长率和弹性模量分别为285.07%、853.38 MPa;断裂伸长率高达275%,扩大至PLLA的59倍,PDBI的21倍,使该聚乳酸基材料由脆性断裂转变为韧性断裂;共混薄膜的阻隔性能先增强后减弱,PLLA/50%PDBI薄膜的O_(2)透过量为309.4 cm^(3)·m^(2)/d,具有良好的阻隔性;同时,PLLA/50%PDBI的水接触角最大,可达78°,材料表面疏水性良好。Poly(lactic acid-co-glycolic acid butylenediyl ester)(PDBI)was synthesized by incorporating poly(butylene glycol itaconate)(PBI)into the main chains of poly(D-lactic acid)(PDLA),and then the PLLA/PDBI blend films were prepared by melt blending the as-synthesized PDBI with poly(L-lactic acid)(PLLA)at different mass ratios.The results indicated that the total crystallinity degree of the blend films presented an increasing trend at first and then de-creased with an increase in the mass ratio of PDBI to PLLA,and the most cubic composite crystals were formed at a PD-BI/PLLA mass ratio of 1/1.At such a mass ratio,the blend films obtained a total crystallinity degree of 9.12%with a melting point as high as 205℃,and their thermal properties were greatly improved.The elongation at break of the blend films exhibited an increasing trend at first and then decreased with an increase in the mass ratio of PDBI to PLLA,where-as their tensile strength and Young′s modulus presented an opposite trend.The PDBI/PLLA blend film at a mass ratio of 1/1 presented a Young′s modulus of 853.38 MPa and elongation at break of 285.07%.There was no change in the tensile strength;however,its elongation at break was 59 times as much as that of PLLA and 21 times as much as that of PDBI,indicating a change from a brittle fracture to the ductile one.The barrier performance of the blend films also showed an enhancement at first and then became weakened.At a PDBI/PLLA mass ratio of 1/1,the blend film exhibit-ed an O_(2) transmission amount of 309.4 cm^(3)·m^(2)/d and a maximum water contact angle of over 78°,indicating good barri-er performance and high hydrophobicity.

关 键 词：聚乳酸 聚衣康酸丁二醇酯 热学性能 力学性能 阻隔性能 

分 类 号：TQ321[化学工程—合成树脂塑料工业]