Electromagnetic Fields in Technology of Processing of Polymeric Materials

Abstract

The issues related to the implementation of the process of depolymerizing of waste polymers, initiated by thermal action of an intense electromagnetic microwave field, are considered. The reactions considered are distinguished by the possibility of reducing the initial monomers or oligomers. The required reaction temperatures are achieved by indirect heating due to the presence of carbon thermal converters in the mixture or the use of liquid reagents characterized by high microwave losses. The results of the study of two different mechanisms of depolymerizing, namely the decomposition of the polymer in a glycol medium and thermal decomposition, are shown. The methods of mathematical modeling of the joint problem of electrodynamics and heat conduction are analyzed to estimate the temperature regimes of the processes of thermal decomposition of polymers. Experimental studies are illustrated by examples of the depolymerizing of polyethylene terephthalate, polystyrene and polymethyl methacrylate, the destruction products of which were esters of terephthalic acid, styrene and methyl methacrylate.