Abstract:

Feasibility of manufacturing wood-waste tire rubber composite(WRC) panels with polymeric methylene diphenyl diisocyanate adhesives(PMDI) and urea-formaldehyde(UF) combination binder system was investigated. The study on correlation of independent variables(board density, hot press time and temperature)could indicate mechanical properties through dependent variables in board manufacturing. And interactive mechanism for independent variables was developed. As test results of dependent variables were statistically analyzed by using response surface method(RSM) on the Design-Expert software to determine the significant variables that influenced board properties. A mathematical simulation or response surface models were developed to predict the board properties(MOR, MOE and IB). The optimal manufacturing conditions for making high quality panels were determined from numerical optimization of Design-Expert software. The results showed that board density, some interactions of independent variables were significant factors that influenced board mechanical properties. Low cost PMDI and UF combination binder system was adopt for manufacturing high quality wood-rubber composites. The optimal board manufacturing conditions were about 170 ℃, 300 s, and 1 000 kg ·m^-3 for hot press temperature, hot press time and board density, respectively. In addition, the microstructure of WRC was deep examined using a scanning electron microscope(SEM), there are strong and smooth interface zone of wood-rubber were also displayed. And the physical and chemical mechanism effects of WRC were developed.

Key words: wood, waste tire rubber, PMDI/UF, correlation, optimal manufacturing