Polyesters, styrylpyridine based

During the course of this study, styrylpyridine based polyesters and polycarbonates as well as their related model compounds were synthesized and characterized by TGA, 01, and UV irradiation to determine the effect of the structure on thermal and UV stability. 

The styrylpyridine based polycarbonates showed similar char yield and oxygen indices (Fig. 2 and Table II) to that of the polyesters. 

An increase of char yield is generally reflected as an improvement in oxygen index. In the styrylpyridine based polyesters and polycarbonate an intermolecular thermally induced Diels-Alder reaction has occurred through the double bond, this increased the char yield and decreased the flammability. The Fries rearrangement, as well as dimerization and isomerization, occurred simultaneously during the UV irradiation of p-VPPB, but no dimerization or isomerization occurred for p,p -BVPDPC, probably due to steric effects. 

High-temperature resists have been formulated from a group of polyesters based on styrylpyridine, which are thermally stable up to 450°C. Such resists have found applications as fine-line solder masks or when the polymer is intended as a permanent eomponent of the final deviee, he it as insulator, interlayer dielectric, or a-particle harrier. ... 

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