Effects of Alkaline Treatment and Particle Size on Physical and Mechanical Properties of Melonhusk-Cellulose/Expandable Polystyrene Composites

The research investigated effects of alkaline treatment and particle size on physical and mechanical properties of melon-husk (MH) filled expandable polystyrene composites. In the process, MH particulate material size of 75 µm, 150 µm, 300 µm, and 600 µm were prepared and modified with alkaline (1%, 2 %, and 3 %,) based on weight volume fraction. The modified fillers, Melonhusk-cellulose (MHC) were analyzed using FTIR after which were subsequently compounded with expandable polystyrene at filler loading to matrix ratio of 25/75 % on a two roll mill compounding machine. The compounded material was passed through a molding and compression machine and after which was cut into dimensions required for analysis and characterization of samples. The result showed that composite prepared with 75 µm particle size and treated with 1 % alkaline has better physical and mechanical properties. The average density and water absorption of the composite was found to be 0.75 gcm-3 and 0.78 % respectively. The tensile strength, modulus of elasticity and elongation at break of the composite were measured and found to be 34.87 MPa, 0.4478 GPa and 8.369 % respectively. The composite had flexural strength and modulus of 56.716 MPa and 2.958 GPa respectively.