生物基核-壳结构阻燃剂构建及其对聚乳酸燃烧、降解和增韧的影响机制

随着能源短缺和环境污染问题的日益加剧，阻燃剂和阻燃材料的研究开始向绿色、可持续的方向发展；本项目将生物基材料与阻燃科学相结合，对高性能阻燃聚乳酸材料展开研究，旨在实现阻燃、增韧与可降解的协同。首先，以天然来源的生物基化合物为反应物，通过静电吸附等方式，围绕壳聚糖设计并合成三种不同类型的核-壳结构阻燃剂，合成过程安全环保，符合绿色化学的发展趋势和要求；其次，通过熔融共混将合成的阻燃剂引入聚乳酸基体并进行纺丝，制备全生物基阻燃、增韧聚乳酸复合材料及纤维；最后，通过多种表征手段综合评价材料的各项性能，系统研究阻燃剂的结构、分散状态、与基体的界面作用以及加工工艺等因素对材料阻燃和增韧过程的影响和作用机制，并对复合材料在微生物、光、热、氧等不同条件下的降解规律和机理进行探讨。本项目是火安全材料领域的创新性探索，对于保护环境、提高阻燃技术水平具有重要的理论价值和现实指导意义。

With the increasing of energy shortage and environmental pollution, the developments of both flame retardants and flame retardant materials turn in the direction of green and sustainable. This proposal aims at realizing the synergy of flame retardant, toughening and degradable in high performance polylactic acid (PLA) materials by the combination of bio-based materials and fire resistance science. Firstly, three different flame retardants with core-shell structure derived from chitosan will be designed and synthesized. All reactants involved in the synthesis of flame retardants are selected from natural bio-based materials. Electrostatic adsorption is the main reacting way during the synthetic process, which makes the whole process safe and environment-friendly, conforming the trend and requirement of green chemistry. Secondly, a fully bio-based flame retardant PLA composites and fibers will be prepared by incorporating the synthesized flame retardants with PLA matrix via melt blending and spinning. Lastly, the flammability, thermal stability and mechanical properties of the composites will be investigated by a variety of characterization methods. The influences of flame retardants structure, dispersion state and interfacial interactions on the flame retardant and toughening properties of the composites will be systematically studied. The degradation mechanisms of the composites under different conditions such as microorganism, light, heat and oxygen will also be discussed. It is suggested that this proposal is an innovative effort in fire safety material fields, which can provide great theoretical and practical significance to the protection of environment and the improvement of flame retardant technology.