Synthesis and properties of some polyesterimides

New polyesterimides have been obtained by condensation of pyromellitic dianhydride with various aromatic diamines and by esterifying, before the actual dehydration, some carboxyl groups of polyamic acid with 4,4′bis (2-hydroxyethoxy) dinaphthyl 1,1′. Some new polyesterimides containing polynaphthalene rings in the side chain have thus been obtained. Thermal properties of the new polymers were studied by thermogravimetric analysis. Investigations were carried out by determining the decomposition temperatures and measuring the weight losses on heating polymer samples under atmospheric conditions in the presence of air. The influence of the structure of the polymers on their properties was investigated.