NOVEL COPOLYAMIDES BASED ON ADIPIC ACID, 1,6-HEXANEDIAMINE AND ALPHA-AMINO-ACIDS .2. STUDY OF PROPERTIES AND THEIR BIODEGRADABILITY FOR FOOD-PACKAGING APPLICATIONS

A novel series of biodegradable copolyamides based on the salt of 1,6-hexanediamine/adipic acid/alpha-amino acids were synthesized by melt polymerization at 250 degrees C. Differential thermal analysis (d.t.a.) and wide-angle X-ray diffraction patterns were employed in order to investigate the semicrystalline/amorphous nature of the synthesized copolyamides. Several methods such as alkali hydrolysis (10% NaOH w/v, 80 degrees C), burial in soil and enzymatic hydrolysis were employed for assessing the susceptibility of these novel copolyamides to degradation. The degradation rates of these copolyamides were evaluated with gel permeation chromatography and d.t.a. measurements and correlated with the cr-amino acid structure and content as well. The fields of food packaging and agriculture (disposable plastics) could be envisaged as potential applications of these novel copolyamides.