聚氯乙烯装饰材料的热分解燃烧特性

THERMODECOMPOSITION AND COMBUSTION PROPERTIES OF POLYVINYL CHLORIDE DECORATING MATERIALS

用热重法研究了聚氯乙烯装饰材料在空气和氮气中的热分解特性 ,并用先进的锥型量热计对这些材料在不同的辐射热通量下的燃烧性能进行了探讨。

Thermogravimetric studies on PVC decorating materials, i.e. PVC floor covering, PVC tile and PVC sheet, have been conducted in the atmospheres:air and nitrogen. These materials begin to decompose at about 200 ℃ producing HCl, and their T1% is quite changeable ranging 170~360 ℃ for each PVC material. The thermal decomposition of PVC materials takes place in three main weight loss stages in the air, whereas in two weight loss stages in nitrogen. Moreover, their fire characteristics, such as ignition times and heat release rates have been measured using the Cone Calorimeter. The Cone results show that heat release rates increased with the increase of heat flux, whereas ignition times decreased as the external heat radiation rose. The minimum heat flux for ignition obtained from the extrapolation of the plots of t -1 i vs heat flux might be used to assess the ease of PVC materials. The minimum fluxes for the three materials are ca 8, 16 and 20 kW/m 2, respectively.