Thermal hazard analysis of styrene monomer at Low temperature conditions during storage and transportation

摘要

Styrene Monomer (SM) has been widely used for producing polystyrene (PS), acrylonitrile-butadiene-styrene (ABS) and styrene-acryonitrile (SAN) in the petrochemical industry. From 1994 to 2001, several serious accidents occurred in Taiwan due to styrene monomer's inherent instability, deviation of operation and others. In this research, thermal polymerization under low temperature is characterized by an isothermal microcalorimeter, thermal activity monitor (TAM). Thermograms show that an autocatalytic reaction occurs in the temperature range from 50 to 80. In addition, the exothermic kinetics is also investigated. Such weakly exothermic phenomena could not be detected by traditional calorimeters such as differential scanning calorimeters (DSC) and vent sizing package (VSP) because of the tiny signal level. Heat of thermal polymerization was determined to be 670+-11 KJmol~(-1); activation energy was also evaluated to be 63+-3 KJmol~(-1) by Arrhenius plot.