The effects of polyol molecular weight and ionization level on the properties of elastomeric polyurethane ionomers were studied. The rubbery plateau modulus was found to depend on the fraction of ionic groups in the material. For the unionized polyurethane, the glass transition temperature of the copolymer was adequately described by the Fox equation. As the ionization level increased, the matrix Tg dropped due to aggregation of the ionized MDI units. Wide-angle X-ray scattering revealed no stress-induced crystallization in an ionomer prepared from a short-chain poly(tetramethylene oxide) polyol. A new morphological model is applied to small-angle X-ray scattering data and the results are compared with the physical property trends.
All Science Journal Classification (ASJC) codes
- Organic Chemistry
- Polymers and Plastics
- Inorganic Chemistry
- Materials Chemistry