Thermal and mechanical characterization of maleimide-functionalized copoly(urethane-urea)s



Maleimide functionalized copoly(urethane-urea)s were prepared by the reaction of a binary mixture of dibenzyldiisocyanate and 5-maleimidoisophthalic diisocyanate with a macrodiol (PEGA-2000), using diethylene glycol and trimethylol-propane as chain extender and crosslinkers in toluene-dichloromethane solutions at the ratio NCO/OH = 1.2. Structures of polymers were confirmed by IR spectroscopy and properties were studied by thermal and mechanical analysis (dynamic mechanical analysis (DMA), differential scanning calorimetry, thermogravimetric analysis, stress-strain) and other physical methods. Maleimide modification increased the storage modulus and Young's modulus of copoly(urethane-urea)s, slightly increased their glass transition temperature from −10.6°C to −6.3°C. Copoly(urethane-urea) networks obtained by thermal polymerization of maleimide functions showed significantly increased of the mechanical properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009