聚合型磷-硅阻燃剂的合成及在聚苯乙烯中的应用

Synthesis of polymeric flame retardant containing phosphorus-silicon and the application in polystyrene

合成了丙烯酸（10-氧-10-氢-9-氧杂-10-磷杂菲-10-基）甲酯（DOPO-CH2O-AA）单体,并通过FT-IR、1H-NMR 确认其结构. 将DOPO-CH2O-AA 和3-甲基丙烯酰氧基丙基三甲氧基硅（KH-570）作为阻燃单元、苯乙烯作为增容单元通过自由基本体聚合制备了聚合型磷-硅阻燃剂（PFR）. 并研究了DOPO-CH2O-AA 和KH-570共聚比例对PFR 的热稳定性和分解成炭能力的影响,确定了最佳的单体比例为n（DOPO-CH2O-AA）/n（KH-570）=6/4.将20%-30%（质量分数）的PFR用于聚苯乙烯阻燃改性,燃烧与热重分析结果符合凝聚相阻燃的特点.其中,当使用30% 共聚组成为n （DOPO-CH2 O-AA）/n （KH-570）/n（St）=48/32/20的阻燃剂阻燃聚苯乙烯时,极限氧指数（LOI）为26.8%,无缺口冲击强度为0.92kJ/m2;热重分析显示,阻燃后聚苯乙烯的起始分解温度在350-360℃,热分解后600℃残炭量高于20%.研究结果表明,PFR中磷-硅元素之间有明显的凝聚相协同阻燃作用.

(10-Oxo-10-Hydro-9-Oxa-10-phosphaphenanthrene-10-yl)methyl acrylate(DOPO-CH2O-AA)has been synthesized and characterized by FT-IR and 1H-NMR.The polymeric flame retardants(PFRs)containing phosphorus-silicon were prepared by free radical bulk copolymerization with DOPO-CH2O-AA,3-methacryloxypropyltrimethoxysilane(KH-570)as fire retardancy units and styrene as the compatibility unit.The influence of DOPO-CH2O-AA/KH-570 ratio on the thermal degradation was studied experimentally.The PFR with n(DOPO-CH2O-AA)/n(KH-570)=6/4presented an optimal charring ability.The 20%-30wt% PFRs were blended with polystyrene,the results of combustion and thermal degradation analysis indicated the condensedphase effect of PFRs.When 30wt% PFR with n(DOPO-CH2O-AA)/n(KH-570)/n(St)=48/32/20 was blended in PS,the LOI of flame retarded polystyrene reached to 26.8% with the impact strength 0.92kJ/m2.The thermo gravimetric analysis(TGA)results showed that the temperature of initial decomposition of the flame retarded polystyrene was 350-360 ℃ and the char yields at 600 ℃ of TGA exceeded 20%in air,it implies that there obviously exhibits synergic flame retardant effect between phosphorus and silicon in the condensed-phase.