Polyesters containing sulfur. VII. New aliphatic-aromatic polyesters for synthesis of polyester-sulfur compositions and polyurethanes

New linear polyesters containing sulfur in the main chain were obtained by melt polycondensation of diphenylmethane-4,4'-bis( methylthioacetic acid) ( DBMTAA) or diphenylmethane-4,4'-bis(methylthiopropionic acid) (DBMTPA) and diphenylmethane-4,4'-bis(methylthioethanol) (DBMTE) at equimolar ratio of r eagents (polyesters E-A and E-P) as well as at 0.15 molar excess of diol (p olyesters E-A(OH) and E-P-OH). The kinetics of these reactions was studied at 150, 160, and 170 degrees C. Reaction rate constants (k(2)) and activation parameters (Delta G(not equa l), Delta H-not equal, Delta S-not equal) from carboxyl group loss were det ermined using classical kinetic methods. E-A and E-P ((M) over bar(n) = 440 0, 4600) were used for synthesis of new rubber-like polyester-sulfur compos itions, by heating with elemental sulfur, whereas oligoesterols E-A(OH) and E-P-OH ((M) over bar(n) = 2500, 2900) were converted to thermoplastic poly urethane elastomers by reaction with hexamethylene diisocyanate (HDI) or me thylene bis(4-phenyl isocyanate) (MDI). The structure of the polymers was d etermined by elemental analysis, FT-IR and liquid or solid-state H-1-, C-13 -NMR spectroscopy, and X-ray diffraction analysis. Thermal properties were measured by DTA, TGA, and DSC. Hardness and tensile properties of polyureth anes and polyester-sulfur compositions were also determined. (C) 1999 John Wiley & Sons, Inc.