次磷酸钙阻燃聚乳酸复合材料的热解特性  

Pyrolysis Characteristics of Calcium Hypophosphite Flame Retarded Polylactide Composite

作　　者：李崇裔 张翔[1] 廖红光[1] 余小光[1] 谈瑛 唐刚[2] LI Chongyi;ZHANG Xiang;LIAO Hongguang;YU Xiaoguang;TAN Ying;TANG Gang(School of Chemical Engineering,Hunan Chemical Vocational Technology College,Zhuzhou,Hunan 412000,China;School of Architecture and Civil Engineering,Anhui University of Technology,Ma'anshan,Anhui 243032,China)

机构地区：[1]湖南化工职业技术学院化学工程学院,湖南株洲412000 [2]安徽工业大学,建筑工程学院,安徽马鞍山243032

出　　处：《塑料》2023年第5期11-15,共5页Plastics

基　　金：湖南省教育厅科学研究项目(19C0641)。

摘　　要：采用熔融共混法制备了一系列的聚乳酸/次磷酸钙(PLA/CaHP)复合材料,使用热重分析仪探究CaHP和PLA/CaHP复合材料的热降解行为,证明了与PLA相比,CaHP的低温分解性造成复合材料的初始分解温度(T_(-5%))、中点分解温度(T_(-50%))和最大热失重温度(T_(max))均显著降低;而且,随着CaHP添加量从5%升高至30%,PLA/CaHP复合材料的T_(-5%)和T_(max)分别约为340、372℃,但是,T_(-50%)从368.4℃升高至373.5℃,提高了约5℃;热重-红外测试结果表明,添加CaHP后,不仅能显著降低热解气相产物的总体含量,而且能有效地抑制碳氢化合物、CO、羰基化合物和芳香族化合物等可燃性气体生成,同时,显著提高了水蒸气和CO_(2)的释放量,这表明,CaHP能够催化基材脱水成炭,通过水蒸气和CO_(2)稀释可燃气体与氧气浓度以及CaHP分解产生的磷酸钙、焦磷酸钙等无机粒子补强炭层,增强抑制可燃气体逸出与热氧交换,从而实现气相与凝聚相的协同阻燃。A series of flame-retardant polylactic acid/calcium hypophosphite(PLA/CaHP)composite were prepared by melt blending method,and thermogravimetric analysis was used to investigate the pyrolysis behaviors of CaHP and PLA/CaHP composite and the obtained results showed that compared with PLA,the initial decomposition temperature(T_(-5%)),the midpoint decomposition temperature(T_(-50%))and the temperature corresponding to the maximum thermal weight loss(T_(max))of the composite were significantly decreased because the decomposition of CaHP readily happened at lower temperature;in addition,the values of T_(-5%)and T_(max)of the composite were fixed at 340℃ and 372℃ approximately,but the values of T_(-50%)of the composite increased from 368.4℃ from 373.5℃ and nearly increased by 5℃;furthermore,thermogravimetric-infrared testing was also carried out,which demonstrated that because of the usage of CaHP,the total content of pyrolysis componets was significantly reduced,but also the formation of combustible gases such as hydrocarbons,CO,carbonyl compounds and aromatic compounds were effectively limited,moreover,the releasing amount of water vapor and CO_(2) obviously rose as well,which indicated that CaHP was capable of promoting the catalytic dehydration of base materials into carbon.In this case,the concentration of combustible gases and oxygen could be diluted by vapor and CO_(2) as well as the formation of inorganic such as calcium phosphate and Calcium pyrophosphate produced by the decomposition of CaHP could contribute a lot to the reinforcement of carbonaceous layer and the suppression of combustible gases escaping as well as heat oxygen exchange,which helped to achieve the synergistic effect of gaseous phase and condensed phase for efficient inflaming retarding.

关 键 词：次磷酸钙 聚乳酸 复合材料 热降解 热解产物分析 

分 类 号：TQ323.4[化学工程—合成树脂塑料工业]