Mechanical properties of Polyurethane / MWCNTs foam sandwich composites

Abstract

This study describes the effect of multi-walled carbon nanotubes (MWCNTs) on the properties, particularly modulus properties of rigid polyurethane (PU) foam produced from palm oil polyol (POP) and methylene diphenyl diisocyanate (MDI). Foam composite in a ratio of 1: 1.1 (% Weight) were mixed and stirred at a speed of 2000 rpm. The addition of MWCNTs into PU foam are varies from 0 wt. % to 3 wt % of filler loading. The foam sandwich structure was prepared by using hand lay-up method to produce pure PU foam sandwich form and (PU / MWCNTs) foam composite, by the attachment of aluminium sheet with an epoxy resin as an adhesive to bind the surface. The properties evaluated were density, compressive strength and compressive modulus. Compression modulus PU foam composites with 2.5% MWCNTs loading showed the highest 1363.753 MPa for PU - MWCNTs compared to other foam composite. For PU / MWCNTs sandwich composite showed the highest compressive modulus at 2.0 wt % which value 1295.368 MPa. It has been proved by the micrograph of morphology by SEM that the cell size reduced as the addition of filler loading increased meaning that the density of the PU foam is higher. The cell size in the PU foam decreased due to the addition of filler loading since there is a reaction called nucleation process occur within the PU foam.