氧化石墨烯改性聚乳酸薄膜的研究

发布时间：2018-01-25 00:25

本文关键词： 氧化石墨烯共价改性聚乳酸阻隔性取向　出处：《南京理工大学》2017年硕士论文　论文类型：学位论文

【摘要】：本文主要研究了氧化石墨烯的聚合物共价修饰及其对聚乳酸薄膜的改性。通过原位缩聚法制备出表面接枝聚乳酸的氧化石墨烯(PLLA-g-GO),并用PLLA-g-GO增强聚乳酸,通过溶液共混法制备了聚乳酸基复合薄膜,之后又对复合薄膜进行拉伸处理。重点考察了聚乳酸基复合材料的力学、热学及阻隔等性能的变化。以乳酸为原料,采用原位缩聚法,一步完成了氧化石墨烯表面的聚乳酸接枝。FT-IR、XPS证明在氧化石墨烯表面接枝了聚乳酸分子链,拉曼和XPS显示PLLA-g-GO在改性过程中发生了部分还原。PLLA-g-GO的表面性能有所变化,能稳定分散在三氯甲烷中。以三氯甲烷为溶剂,采用溶液共混法,制备了聚乳酸/PLLA-g-GO复合薄膜。SEM、XRD结果表明,PLLA-g-GO在聚乳酸基体中均匀分散。TGA和力学测试表明,PLLA-g-GO的添加使复合薄膜的热稳定性和拉伸强度都得到了提高。阻隔性测试表明,PLLA-g-GO的添加显著提高了薄膜对氧气的阻隔性,PLLA-g-GO含量为0.5wt%时,复合薄膜的氧气渗透系数相比纯聚乳酸降低了 77.4%。对聚乳酸/PLLA-g-GO复合薄膜进行单轴拉伸,SEM图片显示,PLLA-g-GO在聚乳酸基体中得到了一定的平面取向,PLLA-g-GO趋于平行于薄膜排列。拉伸后的复合薄膜对氧气的阻隔性大幅提高,其氧气渗透系数低至1.7xl0~(-15)cm~3·cm·cm~(-2)·s~(-1)·Pa~(-1),相比未拉伸的复合薄膜降低了 93.3%。
[Abstract]:In this paper, the polymer covalent modification of graphene oxide and the modification of polylactic acid film were studied. PLLA-g-GOG was prepared by in-situ Polycondensation of poly (lactic acid) oxide (PLLA-g-GOO). Poly (lactic acid) based composite film was prepared by solution blending method with PLLA-g-GO reinforced polylactic acid, and then the composite film was treated by tensile treatment. Using lactic acid as raw material and in situ Polycondensation, the polylactic acid grafted on graphene oxide surface. FT-IR was completed in one step. XPS showed that the poly (lactic acid) chain was grafted on the surface of graphene oxide. Raman and XPS showed that the surface properties of PLLA-g-GO partially reduced. PLLA-g-GO were changed. The poly (lactic acid) / PLLA-g-GO composite film was prepared by solution blending method in the presence of trichloromethane, and the XRD results showed that the composite film was composed of poly (lactic acid) / PLLA-g-GO composite film. PLLA-g-GO was uniformly dispersed in poly (lactic acid) matrix. The thermal stability and tensile strength of the composite films were improved with the addition of PLLA-g-GO. The barrier test showed that the addition of PLLA-g-GO significantly improved the oxygen barrier of the films. The content of PLLA-g-GO was 0.5 wt%. The oxygen permeation coefficient of the composite film was 77.4% lower than that of pure polylactic acid. The uniaxial tensile SEM images of PLA / PLLA-g-GO composite film were shown. The plane orientation of PLLA-g-GO in the polylactic acid matrix tends to be parallel to the film arrangement, and the oxygen barrier of the composite film after stretching is greatly improved. The oxygen permeability coefficient is as low as 1.7 脳 10 ~ (-15) 路cm 路cm ~ (-1) 路s ~ (-1) 路Pao ~ (-1)). Compared with the unstretched composite film, 93. 3% lower.
【学位授予单位】：南京理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB383.2;TQ323.41

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