Hydrogen bonding and mechanical properties in segmented montmorillonite/polyurethane nanocomposites of different hard segment ratios

Hydrogen bonding in the hard segments of the synthesized montmorillonite/po lyurethane nanocomposites of various hard segment ratios was found to decre ase with the increasing amount of montmorillonite regardless of the hard se gment ratios, but reached plateau values at 5 wt% montmorillonite concentra tion. The maximal reductions of the hydrogen bonding in the polyurethane na nocomposites ranged from 20 to 37%, depending on the hard segment ratios as compared to that in the pure polyurethane. The maximal strength and the el ongation at break of the polyurethane nanocomposites increased dramatically as compared to that of pristine polyurethane, and the maximal values occur red at 1 wt% montmorillonite concentration. (C) 2001 Elsevier Science Ltd. All rights reserved.