State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, China.
Innovation Center for Textile Science and Technology, Donghua University, Shanghai 201620, China.
Int J Biol Macromol. 2020 Aug 1;156:314-320. doi: 10.1016/j.ijbiomac.2020.04.025. Epub 2020 Apr 11.
In this research, nanocellulose crystal (NCC) grafted with lactic acid (LA) oligomer was synthesized by one-pot method and used to reinforce the poly(l-lactic acid) (PLLA) matrix. FT-IR, XRD, and C NMR were used to analyze the structure of modified nanocellulose crystal (g-NCC). The results of GPC suggested that the degree of polymerization of the grafted segments was 23, and the degree of hydroxyl substitution of g-NCC was 2.4%. For the g-NCC/PLLA composite, its crystallization rate increases significantly compared with pure PLLA, indicating that g-NCC acted as a nucleating agent to promote the crystallization. Moreover, tensile strength of the composite materials was significantly improved from 41.9 MPa to 53.9 MPa due to the enhanced compatibility. This study provides a fast and effective modification method for g-NCC/PLLA biodegradable composites. According to the above-mentioned experimental results, the g-NCC/PLLA composites can be considered as a potential material in the packaging field, mainly due to its proper biological and physicochemical properties.
在这项研究中，通过一锅法合成了接枝乳酸（LA）低聚物的纳米纤维素晶体（NCC），并将其用于增强聚（L-乳酸）（PLLA）基体。采用 FT-IR、XRD 和 C NMR 对改性纳米纤维素晶体（g-NCC）的结构进行了分析。GPC 的结果表明，接枝片段的聚合度为 23，g-NCC 的羟基数取代度为 2.4%。对于 g-NCC/PLLA 复合材料，与纯 PLLA 相比，其结晶速率显著提高，表明 g-NCC 起到了成核剂的作用，促进了结晶。此外，由于相容性的提高，复合材料的拉伸强度从 41.9 MPa 显著提高到 53.9 MPa。本研究为 g-NCC/PLLA 可生物降解复合材料提供了一种快速有效的改性方法。根据上述实验结果，g-NCC/PLLA 复合材料可以被认为是包装领域的一种有潜力的材料，主要是由于其适当的生物和物理化学性质。
