PREPARATION OF OLIGOMERIC COMPOUNDS BY SOLID-SOLID INTERACTION ROUTE - REACTION OF TEREPHTHALIC ACID (OR TEREPHTHALOYL CHLORIDE) WITH DL-ALPHA-ALANINE

The ability of terephthalic acid or terephthaloyl chloride to interact in the solid phase with DL-alpha-alanine to form oligomeric products was studied by means of DSC and TG/FT-IR techniques. The results sugge st that the polycondensation is mainly dependent on the thermal stabil ity of the dicarboxylic acid or its derivative with respect to the ami noacid. No interaction occurs between the less thermally stable aminoa cid and the dicarboxylic acid, confirming the unreactivity of the amin o group towards the COOH groups. In contrast, the oligomeric species ( with n=9) was obtained by interaction of DL-alpha-alanine with melted terephthaloyl chloride and the reaction mechanism was elucidated by me ans of ESCA measurements.