Effect of cell wall modification of styrene wood polymer with maleic anhydride and glycidyl methacrylate on thermal stability, mechanical behavior and biological resistance of composite

This research was investigated the effect of maleic anhydride and glycidyl methacrylate on thermal stability, mechanical behavior and biological resistance of hornbeam wood polymer containing styrene monomer. Impregnation was performed by vacuum- pressure method using cylinder experimental. Maleic anhydride treated samples were heated in oven for 4 hours at 120ºC. After the impregnation with styrene monomer, polymerization was performed in oven at 90ºC for 24 hours, and at 103±2ºC for the same time subsequently. Bulking of modified wood with maleic anhydride, the presence of styrene in the cell cavities, and interaction between polymer and cell wall through modification with maleic anhydride and glycidyl methacrylate were confirmed by scanning electron microscopy. The branch structure in the reaction of styrene, glycidyl methacrylate and maleic anhydride by wood was resulted in improve the thermal stability of composite. Weight gain due to modification in styrene samples was increased from 24.69% to 42.83 and 44.42 in maleic anhydride/styrene and maleic anhydride/styrene/glycidyl methacrylate samples, respectively. The lowest porosity was in maleic anhydride/styrene/glycidyl methacrylate level with 21% value. The highest improve of mechanical properties was indicated in maleic anhydride/styrene/glycidyl methacrylate level compared to control. Maleic anhydride with double bonds and carboxylate group was showed high reactivity by wood and polymer. Also, difunctional glycidyl methacrylate monomer caused better adhesion of polymer to cell wall through the reaction by hydroxyl group or maleic anhydride and styrene monomer. Significant improve of mechanical properties of modified levels can attributed to interaction of polymer complex with modified cell walls and uniform distribution of polymer in cell lumens. Cell wall modification with maleic anhydride and presence of glycidyl methacrylate were prevented the fungi mycelium development through reduce and blocking of hydroxyl groups and changing the hollocellulose structure, and the presence of polymer in wood as a hard physical barrier.