Hydration and glass transition of hybrid non-isocyanate polyurethanes with POSS inclusions

A non-isocyanate poly (hydroxyurethane) network was synthesized by reaction of a tricyclic carbonate compound with diamines. The system modified two types Polyhedral Oligomeric Silsesquioxane (POSS) molecules, one retaining the crosslinked nature system, and another effectively loosening it. We studied water absorption as function environmental humidity observed that all systems are extremely hydrophilic, absorbing up to 65% when exposed 97% humidity. In parallel, using differential scanning calorimetry dielectric spectroscopy, we effects POSS significant plasticization caused absorbed on glass transition charge mobility. dry materials, crosslinking seems reinforce matrix at least initially slow down mobility while opposite effect is for moiety loosens network. Both inhibit plasticization, both indirectly inhibiting absorption, directly, stiffening network, especially in case POSS.