Poly(ester amide)s derived from L-tartaric acid and amino alcohols. 1. Regic polymers

Stereoregular poly(ester amide)s (PEATn) containing equal amounts of ester and amide groups have been obtained by polycondensation in solution from di -O-methyl-L-tartaric acid and aliphatic amino alcohols H2N(CH2)(n-1)CH2OH. Suitable synthetic routes were designed to prepare either syndioregic (s-PE ATn, n = 5,6) or isoregic (i-PEATn, n = 5, 6, 11) polymers. All the newly s ynthesized poly(tartarester amide)s were characterized by elemental analysi s, size exclusion chromatography, and IR and NMR spectroscopies. They all d isplay optical activity in solution and, except for s-PEAT5, are highly cry stalline with T-m's within the range 100-150 degrees C and T-g's oscillatin g between 10 and 30 degrees C. Thermal decomposition of PEATn onsets above 200 degrees C with T-d values depending upon both the regicity of the chain and the length of the polymethylene segment. For comparative purposes, two poly(esteramide)s, one syndioregic (s-PEAS6) and another isoregic (i-PEAS6 ), were prepared from succinic acid and 6-amino-1-hexanol, and their proper ties were evaluated in parallel. Major differences between PEAS6's and PEAT 6's concerned solubility and hygroscopicity whereas crystallinity and therm al transitions were found to be scarcely affected by the presence of the me thoxy side groups.