氧化铋协同膨胀阻燃聚丙烯的热降解机理  

Thermal degradation mechanism of Bi_2O_3 synergistic intumescent flame retardant polypropylene

作　　者：刘国胜[1,2] 周友[1] 郝建薇[1] 

机构地区：[1]北京理工大学材料科学与工程学院,北京市100081 [2]北京市丰台区公安消防支队,北京市100039

出　　处：《合成树脂及塑料》2013年第5期15-19,共5页China Synthetic Resin and Plastics

摘　　要：以Bi2O3为阻燃协同剂,采用聚磷酸铵(APP)和双季戊四醇复配阻燃体系,制备了具有良好阻燃性能的膨胀阻燃聚丙烯(PP)。Bi2O3的用量为0.10 phr时,膨胀阻燃PP的极限氧指数达25.2%,拉伸强度达28.2 MPa。Bi2O3使APP的热失重速率明显降低,高温质量保持率显著提高;高温时,Bi2O3与APP分解产生的多聚磷酸发生反应,形成Bi—O—P,提高了多聚磷酸的热稳定性。研究表明:燃烧过程中Bi2O3与APP相互作用,生成Bi的磷酸盐,抑制了多聚磷酸分解产生P2O5,使更多的多聚磷酸参与酯化反应,促进体系燃烧成炭,从而形成更加致密的膨胀炭层,提高PP阻燃性能。The intumescent flame retardant polypropylene （PP） with excellent flame retardancy was pre- pared by using Bi203 as synergist in the flame retardant system consisted of ammonium polyphosphate （APP） and di-pentaerythritol. The intumescent flame retardant PP had limited oxygen index and tensile strength up to 25.2% and 28.2 MPa, respectively when the content of Bi203 was 0.1 phr. Adding Bi203 obviously decreased the mass loss rate of APP and significantly enhanced the mass retention rate of APP at high temperature. At high temperature, Bi203 could react with polysphosphorus acid decomposed from APP to form Bi--O--P, which in- creased the thermal stability of polysphosphorus acid. The study indicates that the interaction of Bi203 and APP during combustion generates bismuth phosphate and inhibits polyphosphorus acid to decompose to produce P205, and thus more polyphosphorus acid will be available for esterification reaction and for char formation. Conse- quently, more compact intumescent char layer are formed and the flame retardancy of PP is improved.

关 键 词：聚丙烯 氧化铋 聚磷酸铵 阻燃 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]