Influence of competitive hydrogen bonding between hard and soft segments on the properties of siloxane and polyether based segmented copolymers

Abstract

Quantitative information on hydrogen bonding in urethane and urea type segmented copolymers were obtained through experiments and complementary quantum mechanical calculations. Polymers based on polydimethylsiloxane (PDMS) and polyethers with uniform hard segments were prepared and characterized by FTIR spectroscopy, thermal analysis and stress-strain tests. In addition, quantum mechanical calculations were also performed in determining the extent of intermolecular hydrogen bonding between model compounds. These were achieved by calculating the changes in the enthalpy of formation due to attractive interactions along the minimum energy paths between model molecules.