POSS-Containing Nanocomposites Based on Polyurethane/Poly(Hydroxypropyl Methacrylate) Semi-IPN Matrix

Abstract

AbstractA series of the nanocomposites based on polymer matrix created by method of interpenetrating polymer networks (IPN), consisting of polyurethane and poly(hydroxypropyl methacrylate), and contain 1,2-propanediolisobutyl polyhedral oligomeric silsesquioxanes (1,2-propandiolisobutyl-POSS) as functionalized nanofiller, have been synthesized. 1,2-propandiolisobutyl-POSS nanoparticles were incorporated into the nanocomposites during the process of PU synthesis. The chemical structures, thermodynamic of polymer-filler interactions in the nanocomposites, morphology, thermal properties, and porosity of the created nanocomposites have been investigated. Overall, it was found that POSS nanoparticles are capable to be incorporated into PU polymer chain by chemical reaction between hydroxyl groups of POSS and diisocyanate groups of PU. From thermodynamic parameters, calculations during process of formation of nanocomposites was shown that introduction of small amount of 1,2-propandiolisobutyl-POSS (1–3%) leads to deepening of phase separation in the multicomponent polymer matrix due to embedding of 1,2-propandiolisobutyl-POSS into polyurethane nanodomains. The increasing of 1,2-propandiolisobutyl-POSS amount up to 5–10% results in allocation of nanofiller not only in the PU nanodomains but also in the interphases. This leads to compatibilization in the systems. Result is that the hydroxy-POSS with amount of 5–10% stimulate thermodynamic compatibility of polyurethane and polyhydroxypropyl methacrylate in the nanocomposites. SEM investigations have shown that POSS-diol, introduced in the semi-IPN based on PU and PHPMA on the stage of polyurethane synthesis, acts as nanostructuring agent in the system. As a result, the nanocomposites with more ordered structure are formed so leading to obtaining materials with improved storage moduli. Porosity investigation of the nanocomposites has shown that created materials have the transition pores ranged from 50 to 60 Å and could be used as gas barrier systems.KeywordsNanocompositesPolyurethanePoly(hydroxypropyl methacrylate)Polyhedral oligomeric silsesquioxane (POSS)FTIRThermodynamicsThermal propertiesMorphologyPorosity