Durian is Malaysia''s most popular seasonal fruit, but less than half of the durian fruit is consumed as food. Durian is a type of fruit with a high percentage of waste, which becomes an environmental problem when discarded into the landfill site. Therefore, it is important to utilise durian waste as a potential natural fibre-based composite reinforcement. Durian skin residue is recognised as one of the potential lignocellulosic materials to replace wood in the insulation board industry. The present study aims to develop a low-cost insulation board using durian skin residues as reinforcing materials. Single-layer mats were manually formed, followed by hot pressing using polymeric methane diphenyl diisocyanate (PMDI) resin. The effect of different percentages of PMDI resin (0, 6, 8 and 10%) on the board's physical, mechanical, morphological, and thermal properties was investigated. It was found that 6% PMDI resin is the optimised resin amount to produce PMDI/durian skin fibre composite, and the board with 6% PMDI has the maximum static bending due to enhanced cross-linking by the fibre. In terms of thermal stability and conductivity, the incorporation of 6% of PMDI is considered the best formulation based on the value achieved. The overall results indicated that this study addresses a low-cost innovation for commercial insulation boards as it utilises durian waste and a low dosage of PMDI for implementation in the building and construction industry.

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