基于DOPO-OH和硅氧烷改性LDH的制备及其阻燃环氧树脂

Preparation of Modified LDH Based on DOPO-OH and Siloxane and Its Flame Retarded Epoxy Resins

为了使碳酸根型镁铝水滑石(LDH-CO3^2-)在环氧基体中均匀分散,同时提高其阻燃效果,首先合成了含磷酸10-羟基-9-氧杂-10-磷杂菲-10-氧化物(DOPO-OH),然后利用LDH-CO3^2-的性质,成功制备了通过DOPO-OH官能化和3-氨丙基三乙氧基硅烷(APTS)表面改性的LDH-CO3^2-(LDH-P-Si),采用XRD、FTIR、UV-vis和TG表征了其结构。通过热固化分别制备了含LDH-P-Si和含聚磷酸铵/LDH-P-Si的环氧树脂,采用CCT和TG方法分析了树脂的燃烧性能和热稳定性。结果表明,DOPO-OH官能化和APTS表面改性提高LDH-CO3^2-在高温阶段的热稳定性和成炭能力。LDH-P-Si降低了环氧树脂的燃烧强度,且具有抑烟效果。当加入5%LDH-P-Si时,使环氧树脂到达最大热释放速率的时间延迟了30 s,热释放速率峰值下降了245 k W/m^2,残炭率提高了2.2%,总烟释放、总烟产量和平均比消光面积分别下降了214 m^2/m^2、1.8 m^2、56 m^2/kg。LDH-P-Si与聚磷酸铵复配,进一步提高了其阻燃抑烟性能。LDH-P-Si和APP/LDH-P-Si提高了环氧基质在高温阶段时的热稳定性和成炭量。

In order to solve the dispersion problem of carbonate-type magnesium-aluminum hydrotalcite(LDH-CO3^2-)in epoxy resins and improve its flame-retardant effect,firstly,the acid containing phosphorus,which was named 10-hydroxy-9-oxa-10-phosphorphenanthrene-10-oxide(DOPO-OH),was synthesized.Then,LDH-CO3^2-was functionalized by DOPO-OH and surface modified by 3-aminopropyltriethoxysilane(APTS)to successfully obtain LDH-P-Si according to the properties of LDH-CO3^2-.And its structure was characterized by XRD、FTIR、UV-vis and TG.The epoxy resin containing LDH-P-Si and the epoxy resin containing ammonium polyphosphate(APP)/LDH-P-Si were obtained through the thermal curing process,and their combustion property and thermal stability were analyzed by CCT and TG.The results indicated that LDH-CO3^2-functionalized by DOPO-OH and surface modified by APTS improved its thermal stability at high-temperature stage and carbonforming ability.LDH-P-Si made the combustion intensity of epoxy resin decrease and possessed the smoke suppression effect.When 5%LDH-P-Si was introduced into the epoxy resin,the time to PHRR(peak of heat release rate),PHRR,smoke production release,total smoke production and mean specific extinction area of the epoxy resin were decreased by 30 s,245 k W/m^2,214 m^2/m^2、1.8 m^2、56 m^2/kg,respectively,and the residue of the epoxy resin was increased by 2.2%.When LDH-P-Si was compounded with APP,the flame retardance and smoke-suppression performance of epoxy resin were improved.The thermal stability and carbon production of epoxy matrix at high-temperature stage was increased by incorporating of LDH-PSi and APP/LDH-P-Si.