Mechanical, flammability and thermal degradation characteristics of rice straw fiber-recycled polystyrene foam hard wood composites incorporating fire retardants

Hard wood-polymer composite (HWC) was prepared, based on hot press technique, by mixing air-dried rice straw waste as a filler into a molten of chemically recycled extended polystyrene foam waste (PS) and its maleated form (PS-g-MA) as a matrix. Two fire retardants (FRs), namely zinc borate (ZB) and/or anhydrous magnesium hydroxide (MH), were dispersed into the composite to compensate for the poor thermal stability and flammability of the composite. Thermal properties of the reached HWC were evaluated by different techniques including thermogravimetric analysis, differential scanning calorimetric, in addition to, flammability analyses. Mechanical characterization was, also, rated based on tensile strength and elongation at break measurements. It was found that incorporation of the nominated fire retardants improved the thermal stability of the final products. Besides, flammability resistance was enhanced as ZB and/or MH was added to the hard wood-polymer composite formulation. The onset temperature of degradation and mass loss rates were significantly reduced in the presence of the FRs. The tensile strength of HWC was reinforced by marked additions of the FRs. The obtained data can fulfill the required optimal performance of the HWC to fire and mechanical characterizations which are necessary for many applications in the residential construction, transportation and furniture industries.