Viscoelastic Properties and Formation Simulation of Polyurethane-Polyacrylate Gradient Interpenetration Polymer Networks.

Viscoelastic properties both traditional and gradient polyurethane-polyacrylate IPNs were studied. Both types of IPNs were shown to be two-phase systems inclusive considerable interphase area. It was found that GIPNs were characterized by anisotropy of viscoelastic properties specified by different structure depending on the direction of concentration gradient of acrylate component and which possessed a broad glass transition interval that defined an ability of material to dissipate the mechanical energy. By using the model imitation method the system of questions describing the GIPN formation kinetic - gradient profile generation was proposed. Property-composition correlation dependences were found that allow one to realize the transfer from concentration gradient profiles to those of distribution of properties, in particular elastic modulus, within GIPN layers. [ABSTRACT FROM AUTHOR]