Preparation Of Intumescent Flame Retardant And Study On Flame Retardant Polypropylene

This paper mainly studies the synthesis,thermal stability,the effect of flame retardant and flame-retardant mechanism of Hydroquinol bis[di(2,6,7-trioxa-phospha-bicyclo[2.2.2]-octane-1-oxo-4-hydroxylmethyl)]phosphate(PBPP)and triazine charring agent.The synergistic flame-retardant,mechanism and mechanical property of triazine charring agent and Halloysite nanotubes(HNTs)are investigated.The main research results are listed as following:(1)PBPP is synthesized by 1-oxo-4-hydroxymethy 1-2,6,7-trioxa-1-phosphabicy-clo[2.2.2]octane(PEPA),Hydroquinone(C6H4(OH)2)and hosphorus oxychloride(POCl3).The water resistance,compatibility with polypropylene(PP),thermal stability,minimal addition,effect of PP/IFR(PBPP)and flame-retardant mechanism is investigated.The experimental results show that PBPP has better performance than PEPA and pentaerythritol(PER)in water resistance,compatibility with PP,thermal stability and flame retardance of PP/IFR systems.The PP/IFR systems reach UL94 V-0 flammability rating when the minimal addition of IFR with PBPP,PEPA or PER is 25%,23%and 28%,respectively.PBPP forms a perfect charring layer,with the high carbon content of PBPP help it form the charring layer more quickly.(2)Triazine-based charring agent is synthesized by cyanuric chloride(C3N3Cl3)and diamine.The water resistance,thermal stability,minimal addition and effect of PP/IFR is investigated.The experimental results show that PP/IFR systems has good water resistace properties and thermal stability.When the mass ratio of APP/triazine-based charring agent is 2:1 and the content is 28wt.%,the flame retardant PP meet UL-94 V-0 rating.The flame retardant mechanism is the flame retardants decompose to NH3 and form a stable charring layer during burning.(3)PP/IFR/HNTs composites are prepared by IFR(triazine-based charring)and halloysite(HNTs).It finds that HNTs and IFR has a synergistic effect of intumescent flame retardant of polypropylene.The flame retardant property of the PP/IFR/HNTs system reach UL94 V-0 rating when IFR and HNTs addition are 17wt.%and 3wt.%.When the composites is burning,HNTs and APP form a crosslinking carbon layer.HNTs has a good framework support role in carbon layer.Based on two reasons,PP/IFR/HNTs has a good performance on flame retardant PP.HNTs improves the mechanical property of PP/IFR,because of the structure of HNTs,which support the material.