环氧树脂包覆聚磷酸铵-聚丙烯阻燃体系构建
Construction of epoxy resin coated ammonium polyphosphate-polypropylene flame retardant system
孙维根 1陈葵 1刘成娟 1王超 1武斌 1纪利俊 1吴艳阳1
作者信息
- 1. 华东理工大学化工学院,上海 200237
- 折叠
摘要
为构建膨胀聚丙烯(PP)阻燃体系,采用原位聚合法制备环氧树脂包覆聚磷酸铵微胶囊(EP-APP)以改善APP与PP材料的相容性,并选用季戊四醇(PER)为成炭剂与EP-APP构成膨胀型阻燃剂(IFR),制备PP/EP-APP/PER阻燃复合材料.以微胶囊的水溶性为指标优化微胶囊包覆工艺,考察了EP-APP与PER质量比和IFR添加量对复合材料的阻燃性能及力学性能的影响,分析了IFR中EP-APP与PER的反应机理.结果表明,当EP加入量为APP质量的10%、固化剂三乙烯四胺(TETA)用量为EP质量的15%时,采用40℃(1 h)+70℃(1 h)的固化反应温度设置,可制得有良好耐水性的EP-APP微胶囊.当IFR质量分数为25%,IFR中EP-APP与PER质量比为3∶1时,制得PP/APP/PER阻燃复合材料的极限氧指数(LOI)达到35.0%,垂直燃烧性能达到UL 94 V-0等级,且复合材料仍能保持较好的拉伸性能.热重分析表明,IFR的分解反应可分为三个阶段:首先是EP-APP受热分解后与PER发生反应,生成含有磷酸酯键的物质;然后是酯类化合物生成稳定的环状酯并释放出H2O和NH3;最后上述产物进一步形成双环及多环磷酸酯并在高温下炭化形成致密的炭层,隔氧隔热从而发挥阻燃作用.
Abstract
In order to construct an intumescent polypropylene(PP)flame retardant system,epoxy resin coated ammonium polyphosphate microcapsules(EP-APP)were prepared by in-situ polymerization to improve the material compatibility of APP and PP.Meanwhile pentaerythritol(PER)was selected as a carbon-forming agent forming an intumescent flame retardant(IFR)with EP-APP to prepare PP/EP-APP/PER flame retardant composites.The water solubility of microcapsules was used as an index for the microcapsule coating process optimization,the effects of the mass ratio of EP-APP and PER and the addition of IFR on the flame retardant properties and mechanical properties of the composites were investigated,and the reaction mechanism of EP-APP and PER in IFR was analyzed.The results show that when the amount of EP is 10 wt%of the APP amount and the dosage of the curing agent triethylenetetramine(TETA)is 15 wt%of the EP amount,the curing reaction temperature of 40℃(1 h)+70℃(1 h),the EP-APP microcapsules with excellent water resistance can be prepared.When the IFR addition amount is 25 wt%and the mass ratio of EP-APP to PER was 3∶1,the limiting oxygen index(LOI)of the prepared PP/APP/PER flame retardant composites reaches 35.0%,and the vertical combustibility reaches UL 94 V-0 grade,and the material maintaines good tensile properties.Thermogravimetric analy-sis shows that the decomposition reaction of IFR can be divided into three stages.First,EP-APP reacts with PER after thermal decomposition,forming a substance containing phosphate bonds.Then,the ester compounds produce stable cyclic esters and release H2O and NH3.Finally,the above products form bicyclic and polycyclic phosphates and carbonize at high temperature to form a dense carbon layer,which is oxygen and heat insulation to play a role of flame retardant.
关键词
聚丙烯/环氧树脂/聚磷酸铵/水溶性/性能测试/反应机理Key words
polypropylene/epoxy resin/ammonium polyphosphate/water solubility/performance testing/reaction mechanism引用本文复制引用
出版年
2024
NETL
NSTL
万方数据