Poly(alkyl methacrylate)와 난연제인 tetrabromobisphenol-A(TBBA)의 혼합물에 대한 열분해 거동을 50ml/min의 질소기류하에서 가열속도 4-20℃/min으로 변화시키면서 thermogravimetric analysis(TGA), gel per-meation chromatography(GPC), infra-red spectroscopy(IR) 및 gas chromatography(GC)로 추적하였다. 이들 혼합물의 열분해 활성화에너지는 Friedman 법을 사용하여 구하였고, PMMA/TBBA=95/5, PEMA/TBBA=97/3 과 PBMA/TBBA=97/3의 혼합비에서 열적으로 더 안정되었다. 이들 혼합물의 GPC 분석에서는 분해온도증가에 따라 점도평균분자량이 완만히 감소하였고, IR 분석에서 carbonyl index값은 반응온도와 시간의 증가에 따라 느리게 증가하였다. 이들 혼합물의 열분해반응은 주쇄분해반응으로 이루어진다.
The thermal degradation behavior of poly(alkyl methacrylate)and flame-retardant, tetrabormobis-phenol-A(TBBA) mixture was analyzed using the Gel Permeation Chromatography(GPC), Infra-red Spectro-scopy(IR), Gas Chromatography(GC) and Thermogravimetric Analysis(TGA) under nitrogen gas flow of 50ml/min at various heating rates ranging from 4 to 20℃/min. The activation energy of thermal degradation in the mixture was determined using the Friedman method. The optimum thermal stabilization was obtained in PMMA/TBBA=95/5, PeMA/TBBA=97/3 and PBMA/TBBA=97/3 blend. At GPC analyses, the viscosity average molecular weight in the mixture was decreased slwoly with decomposition temperature. At IR analy-ses, the value of carbonyl index in the mixture was increased slowly with reaction time and temperature. The thermal degradation mechanism of poly(alkyl methacrylate) and TBBA mixture was observed to be main chain scission under nitrogen environment.
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