effect of chemical modification of wood flour on the static and dynamic mechanical properties of polypropylene based composites

in this study, the effect of chemical modification of wood flour on the mechanical properties of polypropylene based composites was investigated using by dynamic mechanic thermal analysis. to meet this objective, the wood flour treated with chemical components including alkaline, acetic acid and benzoyl chloride, and then the chemically treated fibers were compounded with polypropylene at 180 °c, 60 rpm and 60 wt%, in an internal mixer. the samples were made by injection molding. static mechanical tests including bending and tensile were performed. dmta test in the range of -60 to 120 0c with 5 0c/min temperature rate and 1 hz frequency was done. changes in the chemical structure of chemically treated fibers were tracked by fourier transform infra-red (ftir) spectroscopy. results indicated that the mechanical strength, storage modulus and loss modulus of samples increased by chemical modification; however, the mechanical loss factor decreased. also, the glass transition temperature and alpha transition in the chemically treated samples transmitted to higher temperatures. the reduction in the intensity of o-h bond at 3400 cm-1 and the formation of the ester bond at 1740 cm-1 represents the change in the chemical structure of the fibers as a function of chemical modification.