Wang Feiyue, Liao Jiahao, Yan Long, Cai Mengtao
Institute of Disaster Prevention Science and Safety Technology, School of Civil Engineering, Central South University, Changsha 410075, China.
Polymers (Basel). 2022 Jun 12;14(12):2375. doi: 10.3390/polym14122375.
A unique mono-component intumescent flame retardant, named PPy-MAPP, of which melamine-coated ammonium polyphosphate (MAPP) was microencapsulated by polypyrrole (PPy), was synthesized and carefully characterized. The obtained PPy-MAPP was applied to epoxy resin (EP) for obtaining flame-retarded EP composites. The results show that PPy-MAPP imparts better flame retardancy and smoke suppression properties to EP compared to the same addition of MAPP. The EP composite with 15 wt% PPy-MAPP easily passes the UL94 V-0 rating and achieves an LOI value of 42.4%, accompanied by a 61.9% reduction in total heat release (THR) and a 73.9% reduction in total smoke production (TSP) when compared with pure EP. The char residue analysis shows that PPy-MAPP can promote a generation of more phosphorus-rich structures in the condensed phase that improve the integrity and intumescence of char against fire. The mechanical test indicates that PPy-MAPP has a less negative effect on the tensile strength and elastic modulus of epoxy resin due to the good compatibility between PPy-MAPP and the EP matrix, as supported by differential scanning calorimetry (DSC) analyses. In this paper, these attractive features of PPy-MAPP provide a new strategy to prepare satisfactory flame retardant and super flame retarding EP composites.
合成了一种独特的单组分膨胀型阻燃剂，命名为PPy-MAPP，其中三聚氰胺包覆的聚磷酸铵（MAPP）被聚吡咯（PPy）微胶囊化，并对其进行了详细表征。将所得的PPy-MAPP应用于环氧树脂（EP）以制备阻燃EP复合材料。结果表明，与相同添加量的MAPP相比，PPy-MAPP赋予EP更好的阻燃性和抑烟性能。含有15 wt% PPy-MAPP的EP复合材料轻松通过UL94 V-0等级测试，极限氧指数（LOI）值达到42.4%，与纯EP相比，总热释放（THR）降低了61.9%，总烟生成量（TSP）降低了73.9%。残炭分析表明，PPy-MAPP可以促进在凝聚相中生成更多富含磷的结构，从而提高残炭在火灾中的完整性和膨胀性。力学测试表明，由于PPy-MAPP与EP基体之间具有良好的相容性，PPy-MAPP对环氧树脂的拉伸强度和弹性模量的负面影响较小，差示扫描量热法（DSC）分析也证实了这一点。本文中，PPy-MAPP的这些吸引人的特性为制备令人满意的阻燃和超阻燃EP复合材料提供了一种新策略。
