UV enhanced gas–solid synthesis of chlorinated poly vinyl chloride characterized by a UV–Vis online analysis method

doi:10.1016/j.cjche.2014.12.002

Abstract

Abstract: Dynamic characteristics of UV enhanced gas-solid PVC chlorination process were revealed by a UV-Vis spectral online analysis method. Experimental results showed an instantaneous increase of the chlorination rate as soon as UV lightwas affiliated, which demonstrated the intensified effect of UV radiation on PVC chlorination directly. Different affiliationmethods of UV light were then studied, proving that continuous UV radiation could enhance the chlorination process significantly while intermittent UV radiation was able to initiate the chlorination reaction once it was conducted. Besides, experiments were carried out to study the influences of parameters on the chlorination process such as UV wavelength, chlorination temperature, partial pressure of chlorine gas and PVC raw materials. Among all the parameters, chlorination temperature and partial pressure of chlorine gas were testified as two key factors to determine the chlorination performance. Thermal analysis of CPVC products showed that their corresponding properties such as the glass transition temperature (T_g) and the homogeneity of chlorine distribution in polymer phase were improved with the increase of chlorine content.

Key words: Polymer, Photochemistry, UV&ndash, Vis online analysis, Dynamic characteristics, Chlorinated poly vinyl chloride

摘要： Dynamic characteristics of UV enhanced gas–solid PVC chlorination process were revealed by a UV–Vis spectral online analysis method. Experimental results showed an instantaneous increase of the chlorination rate as soon as UV lightwas affiliated, which demonstrated the intensified effect of UV radiation on PVC chlorination directly. Different affiliationmethods of UV light were then studied, proving that continuous UV radiation could enhance the chlorination process significantly while intermittent UV radiation was able to initiate the chlorination reaction once it was conducted. Besides, experiments were carried out to study the influences of parameters on the chlorination process such as UV wavelength, chlorination temperature, partial pressure of chlorine gas and PVC raw materials. Among all the parameters, chlorination temperature and partial pressure of chlorine gas were testified as two key factors to determine the chlorination performance. Thermal analysis of CPVC products showed that their corresponding properties such as the glass transition temperature (T_g) and the homogeneity of chlorine distribution in polymer phase were improved with the increase of chlorine content.

关键词: Polymer, Photochemistry, UV&ndash, Vis online analysis, Dynamic characteristics, Chlorinated poly vinyl chloride

Qianli Yang, Wei Lu, Lin Bai, Binhang Yan, Yi Cheng. UV enhanced gas–solid synthesis of chlorinated poly vinyl chloride characterized by a UV–Vis online analysis method[J]. Chin.J.Chem.Eng., 2015, 23(6): 1052-1059.

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