Thermal degradation of poly 4-(2-napthalene sulfonyl) styrene

Abstract

Poly 4-(2-napthalene sulfonyl) styrene [poly(NPS)I, a new functionalized polystyrene (PS), was synthesized by sulfonylating polystyrene with the corresponding sulfonyl chloride in the presence of the Friedel-Crafts catalyst at room temperature. The polymer has been characterized by Fourier transform infrared (FTIR) and nuclear magnetic resonance spectroscopy. Thermogravimetric studies show that the thermal stability of the sulfonylated PS is much higher than that of PS. The thermal degradation of poly(NPS) was studied at 500 degrees C under vacuum. The volatile fractions were characterized by FTIR and gas chromatography/mass spectrometry (GC/MS) techniques. The principal reactions are depolymerization and random chain scission. The activation energy of thermal decomposition in different weight losses of poly(NPS) was found as 16.56 kcal/mol by using the multiple heating rate kinetic method. A mechanism of depolymerization, very similar to those of various polystyrenes, can be proposed.