Abstract
Reinforced polyurethane−urea nanocomposite with reactive polyhedral oligomeric silsesquioxanes (POSS) has been prepared via environmentally friendly aqueous dispersion with no organic solvent. Rheological behavior of this important class of materials has been investigated as a function of POSS concentration over a wide range of shear frequency and temperature (−100 to 230 °C). The functionalized diamino-POSS was reacted initially with isophorone diisocyanate (the urethane hard segments) before adding the polyester diol (the soft segments). The complete reaction of diamino-POSS with urethane segments was confirmed rheologically and morphologically (TEM). The molecular relaxations of the hard and soft segments of PU/POSS nanocomposites were investigated using the rectangular torsional mode in the glassy and rubbery states. It was found that the storage elastic modulus increased systematically only in the high-temperature range (i.e., the range of the Tg of the urethane segments) while the modulus did not si...
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call