Polyurethanes (PUR) are commonly used materials in the medicine, automotive and mining industry. Fumed silica nanoparticles (nanosilicas) are fillers commonly added to improve the thermal, rheological and mechanical properties of polyurethane.
In this study, nanocomposites with nanosilica and modified nanosilica with a –NCO group were obtained. The aim of these studies was to develop and compare polyurethane nanocomposites containing from 0.5% to 4% wt of nano SiO2 and modified nanosilica. Polyurethane (PU)/nanosilica composites were obtained from “in situ” polymerization using polyester polyols of molecular weight ~1940 Da, 4,4 diphenyl methane diisocyanate (MDI), dicyandiamide as a chain extender and silica dioxide as a nanofiller. According to the amount of nanofiller, density, abrasive wear and wet angle of nanocomposites were investigated. Thermal properties such as degradation processes with thermo gravimetric analysis (TGA) and glass transition with differential scanning calorymetry (DSC) were determined. Glass transition, is one of the most important properties in determining the suitability of a polymer in an engineering application. Shifting of the glass transition after using nanofiller has been reported by many authors. In our case no significant difference was observed. The comparison of the FTIR spectra of composites with PU matrix, allows us to detect differences in characteristic bonds area.