磷-氮膨胀型阻燃聚甲醛的制备与性能研究

Preparation and performance of phosphorus-nitrogen intumescent flame retardant polyoxymethylene

采用包覆红磷、酚醛树脂、双季戊四醇和三聚氰胺构成复合无卤膨胀型阻燃体系,与聚甲醛(POM)经共混挤出制备阻燃聚甲醛材料。当聚甲醛、包覆红磷、酚醛树脂、双季戊四醇、三聚氰胺的质量分数分别为65%、15%、4%、6%、10%时,材料的极限氧指数可以达到39%,垂直燃烧级别可以达到UL 94 V-0级。阻燃填料的加入对材料的力学性能有较大影响。采用数码照片、红外光谱(FT-IR)、扫描电子显微镜(SEM)等对材料燃烧后的炭层进行了研究,采用热重分析(TG)、差示扫描量热仪(DSC)、动态机械热分析(DMA)等对材料的热性能进行了探讨。

Flame retardant polyoxymethylene （POM） ranked as UL 94 V-0 is prepared by utilizing a halogen-free intumescent system with encapsuled red phosphorus （ RP ）, novolac resin, dipentaerythritol （ DPET）, and melamine （ME） as raw materials. When the mass fraction of POM, RP, Novolae, DPET and ME is 65 % , 15 % , 4% , 6% and 10% , respectively, the limited oxygen index （LOI） can be as high as 39% , and the vertical burning level can be ranked as UL 94 V-0. Nevertheless, the addition of flame retardant additives has adverse influences on the mechanical properties comparing with unmodified POM. Digital photo, fourier transform infrared spectral （FT-IR） and scanning electron microscope （SEM） are utilized to analyze the residual carbon after burning test. Thermo-gravimetric analysis （TGA） and dynamic mechanical analysis （DMA） are employed to investigate the thermal stabilities and dynamic properties of flame retardant POM.