微胶囊聚磷酸铵的制备及阻燃环氧树脂的性能研究

Study on Preparation of Microencapsulated Ammonium Polyphosphate and Properties of Flame Retardant Epoxy Resin

采用三聚氰胺甲醛树脂预聚物通过原位聚合法制备了微胶囊聚磷酸铵阻燃剂(MAPP),利用扫描电镜观察到MAPP颗粒表面包覆了一层树脂。采用热重分析法、垂直燃烧法和氧指数法研究了聚磷酸铵(APP)和MAPP阻燃环氧树脂材料的热性能及阻燃性能。结果表明:与APP相比,MAPP阻燃环氧树脂的最大失质量温度、残炭量以及阻燃性能均显著提高。添加10%APP或MAPP的环氧树脂材料的氧指数均大于27.0%,阻燃性能均达到UL 94 V-0级,且MAPP样条燃烧后可形成膨胀炭层。相比于APP,MAPP阻燃材料的力学强度均有所改善,当阻燃剂填充10%时材料的拉伸强度从32.6 MPa提高到35.7 MPa,冲击强度从10.8 kJ/m2提高到11.6 kJ/m2,均高于纯环氧树脂材料的力学强度。

Microencapsulated ammonium polyphosphate（MAPP）was prepared by covering the melamine-formaldehyde resin onto the surface of ammonium polyphosphate（APP）through in-situ polymerization,which was confirmed by SEM.The heat resistance and flame retardancy of APP and MAPP flame retarede epoxy resin were studied by thermogravimetry,vertical burming and limiting oxygen index.Rrsults showed that the maximum weight-loss temperature,char yield and flame retardancy of MAPP composites were improved obviously when compared with APP.When the content of APP or MAPP was 10%,LOI values of EP composites were higher than 27.0%,and reached V-0 level of UL94 and the intumescent char layers were formed in the burmiong process of the samples with MAPP.Compared with APP,the mechanical properties of MAPP filled composites were improved to a certain level,when the content of flame retardant was 10%,the tensile strength increased from 32.6 MPa to 35.7MPa,and the impact strength increased from 10.8kJ/m2 to 11.6kJ/m2,which were higher than that of pure expoxy resin.