摘要
通过溶液刮涂法,将浓度均为0.04 g/mL的左旋聚乳酸(PLLA)和右旋聚乳酸(PDLA)溶液用刮涂机层层交替涂覆烘干后制备成薄膜,并将PDLA/PLLA(1∶1)共混溶液及纯PLLA溶液用涂布机采用相同的方法制备出薄膜作为对比样。通过差示扫描量热分析、二维广角X射线衍射、扫描电子显微镜、万能拉伸机、压差法气体渗透仪研究了PDLA/PLLA交替多层结构对PLA结晶行为、微观形貌、力学性能及氧气阻隔性能的影响。结果表明,PLLA层与PDLA层之间可以形成二维连续立构晶层,二维连续立构晶层(2D-SC)还可以作为成核剂,诱导两侧连续有序PLLA横晶(PLLA-TC)与PDLA横晶(PDLA-TC)的生成。2D-SC晶体、PLLA-TC晶体及PDLA-TC晶体的存在可以大幅度提升聚乳酸的气体阻隔性能。
By solution coating method,l-polylactic acid(PLLA)and d-polylactic acid(PDLA)solutions with the concentration of 0.04 g/mL were alternately coated by scraping machine layer by layer and dried to prepare the films,and PDLA/PLLA(1∶1)blend solution and pure PLLA solution were prepared by coating machine at the same way to prepare the films as comparison sample.By differential scanning calorimetry(DSC),two-dimensional WAXD,SEM,universal drawing machine and differential pressure gas permeometer,the effects of PDLA/PLLA alternating multilayer structure on the crystallization behavior,microstructure,mechanical properties and oxygen barrier properties of PLA were studied.The results show that the two-dimensional continuous stereocomplex crystallites(2 D-SC)could be formed between PLLA layer and PDLA layer,and the two-dimensional continuous stereocomplex crystallites(2 D-SC)could also be used as nucleating agent to induce the generation of continuous ordered PLLA transcrystalline(PLLA-TC)and PDLA transcrystalline(PDLA-TC)on both sides.The presence of 2 D-SC,PLLA-TC and PDLA-TC can greatly improve the gas barrier properties of PLA.
作者
高营营
李姜
郭少云
Yingying Gao;Jiang Li;Shaoyun Guo(State Key Laboratory of Polymer Materials Engineering,Sichuan Provincial Engineering Laboratory of Plastic/Rubber Complex Processing Technology,Polymer Research Institute of Sichuan University,Chengdu 610065,China)
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2020年第8期104-108,共5页
Polymer Materials Science & Engineering
基金
国家自然科学基金资助项目(51873112)
四川省科技厅应用基础(重大前沿)(2018JY0548)。
关键词
聚乳酸
二维连续
立构晶
横晶
polylactic acid
two-dimensional continuous
stereocomplex crystallites
transcrystalline
