不同无卤阻燃复合体系对全水发泡聚氨酯泡沫结构与性能的影响

以聚磷酸铵(APP)为主阻燃剂,采用"一步法"工艺制备了环保高效的无卤阻燃全水发泡半硬质聚氨酯泡沫。通过旋转黏度计、扫描电子显微镜、氧指数测量仪、水平垂直燃烧仪、万能材料试验机研究了聚磷酸铵与氢氧化铝(AH)、甲基磷酸二甲酯(DP)的无卤阻燃复合体系对聚氨酯泡沫的发泡行为、结构与性能的影响及规律。研究表明,各无卤阻燃复合体系物料的黏度均随APP用量增加而增大,当APP用量大于30pphp时,黏度增幅变大,尤以添加AH的体系为最。各体系的氧指数均表现出随APP用量增加而增大的趋势,并在APP用量为60pphp时趋于相近值(26.7%),APP/DP体系只能达到垂直燃烧的V-2级别,而只添加APP和APP/AH体系均未达到垂直燃烧级别。只添加APP的体系和APP/AH体系在APP量较高时均因物料黏度大反应过热导致体系发泡不稳定出现内部缺陷,压缩性能下降。

Effect of Different Halogen-Free Flame Retardant System on the Structure and Performance of Water Blown Semi-Rigid Polyurethane Foam

Environment-friended,high efficient halogen-free flame retardant water blown semi-rigid polyurethane foam(SPUF),in which ammonium polyphosphate (APP) was used as main flame,was obtained through one-shot,free-rise method.Effects of different halogen-free flame retardant systems containing APP,aluminum hydroxide (AH) and dimethyl methylphosphonate (DP) on the foaming behavior,structure and properties of SPUF were studied by rotary viscosimeter,SEM,limiting oxygen index test (LOI),horizontal-vertical burning test,universal material testing machine.Experimental results show that the viscosity of component A of all the two substance systems is enhanced with the increasing loading of APP.Larger enhancement of the viscosity in each system is found when the APP content reaches 30pphp,especially for APP/AH filled systems.The limiting oxygen index (LOI) of all the two substance systems increases with the increasing APP loading and is up to the same value (26.7％).APP/DP system reaches the V-2 rating in the vertical burning test,however,only APP filled system and APP/AH system don't get through any vertical burning test rating.The compression property of system with APP only and system of AH =15 APP 0～60 is deteriorated because of its inner defects,which is due to the reaction heat accumulation caused by the high viscosity of system,when the APP loading is high.