Effect of the diisocyanate and chain extenders on the properties of the cross-linked polyetherurethane elastomers

Polyurethane elastomers with potential for applications in damping bearings were synthesized with 1,6-hexamethylene diisocyanate, 4,40-methylenebis-(phenylisocyanate), poly(1,4-butane)diols (Terathane 1400), 1,4- butane diol 1,6-hexane diol and glycerin chain extenders. The glass-transition temperatures of the materials ranged from -42 to -75 C and were higher for polymers based on 4,40-methylenebis-(phenylisocyanate) and with higher hard segment (HS) contents. The tensile strengths of the materials were 20–55 MPa and the tensile moduli were 30– 134 MPa. These increased with increasing HS content. Interchain cross-linking improves thermal stability, which was measured by thermogravimetric analysis and differential scanning calorimetry. The structure and amount of HS used causes a significant variation in the properties of cross-linked elastomers