MICROSTRUCTURAL CHARACTERISATION, RHEOLOGICAL AND WATER ABSORPTION PROPERTIES OF FILLED POLYURETHANE FOAM

Abstract

This work investigates the microstructural characterization, rheological and water absorption properties of granite and feldspar filled polyurethane foam. Foaming of polyurethane with the use of synthetic materilas as suitable additives remain a major setback for polyurethane foams. Hence, granite and feldspar are selected as the fillers, pulverized and sieved to ˂90 µm and are randomly dispersed into the polyurethane matrix. The matrix constituents were mixed in the same ratio while fillers were introduced via a one-shot system approach in predetermined proportions of 3-7 wt%. The work was carried out to identify optimum fillers to be utilized in the production of rigid polyurethane foams given the effect of the fillers on the microstructural characterisation, rheological and water absorption properties of the foams. SEM, XRF and FTIR analysis were used characterize the foams while rheological and water absorption tests are also carried out. The presence of the fillers in the foam showed a rupture in the structure of the foams with the cells having similar arrangements. The cream, gel, rise, and the tack-free time was delayed with the presence of the filler particles. It was discovered that 7 wt% feldspar addition enhances the cream and gel time while 3 wt% granite enhance rise and tack free time, respectively in the optima conditions. It was discovered that the two fillers had inverse effects on the rheological properties. The addition of granite and feldspar degrades the sulfonic acid groups and promoted the appearance of Si-O stretching vibration band