Moisture absorption, thermal and microstructural properties of polymer composites developed from rice husk and polystyrene wastes
Joshua O. Ighalo, Adewale George Adeniyi, Oluwasemilogo O. Owolabi, Sulyman A. Abdulkareem
Abstract
Polymer composites have been prepared with natural fibres as fillers/reinforcement to improve the mechanical properties and obtain the characteristics demanded in specific applications. In this study, the moisture absorption behaviour, thermal conductivity and microstructural p roperties of rice husk reinforced polystyrene composite, developed by solvent casting method was investigated. The filler particle size was 20 µm. The moisture absorption was investigated by immersion tests, thermal conductivity was investigated using the guarded hot plate apparatus, whilst the microstructural property of the composite was studied at 40× and 100× magnifications by an optical microscope. It was observed that moisture absorbed increased with increasing time and composites with a higher composition of filler absorbed more moisture than those with a lesser amount of fillers. The sample with 20 wt% filler had the lowest equilibrium/saturation point (5.79 wt%) achieved after just 5 hours. The sample with 30 wt% filler had the highest moisture diffusivity and mass transfer kinetic constant of 1.14 × 10−4 mm2/s and 2.013 hr−1 respectively. The maximum thermal conductivity of 1.7 W/moC was observed at 40 wt% filler loading. Microstructural analysis revealed that the best fibre-polymer mix was achieved at 40 wt% filer loading.