Benzene;benzene-1,3-dicarboxamide

synthetischePoly(m-phenylene isophthalamide is produced by reaction of isophthaloyl chloride and m-phenylenediamine: This reaction occurs rapidly in the presence of an acid acceptor under mild conditions. The conventional melt polymerization techniques, as used for the preparation of nylons, cannot be applied to aromatic polyamides since the melting points of the polymers are too high. Polymerization is therefore conducted either in solution (e.g. in methylene chloride) or in suspension. In the latter case, the diamine is dissolved in water, together with an acid acceptor (e.g. sodium carbonate) and the diacid chloride is dissolved in a solvent which is immiscible with water (e.g. carbon tetrachloride or cyclohexanone). The two solutions are then subjected to intensive mixing. Rapid reaction occurs at the liquid interface or just inside the solvent boundary and this technique is therefore commonly termed interfacial polymerization.