New poly(ester-b-aliphatic) and poly(ester-b-ether) multi-block elastomers contg. poly(trimethylene terephthalate) hard segment and linoleic acid dimer or polyoxyethylene soft segment were prepd. and studied by H-1 NMR and FTIR methods to confirm their chem. structures and by DSC and DMTA to det. their thermal properties. Some of the polymers were studied for degradability in soil and during hydrolysis (pH 7). In both cases, a decrease in intrinsic viscosity was obsd.