Optimization of tensile strength for new type acetone-urea-formaldehyde furan resin using uniform design

In this study, the 24 h tensile strength of new type acetone-urea-formaldehyde furan resin (nitrogen content 3%) was investigated by uniform design optimization. Four independent variables such as acetone : formaldehyde molar ratio (mol/mol), solution pH value, reaction temperature (degrees C) and reaction time (min) were considered in the experiments. U*13(13(4)) uniform design was employed and the equation of 24 h tensile strength model was obtained after 13 experimentations. The 24 h tensile strength was optimized by applying single factor experiments and stepwise non-linear regression analysis. Minitab (Minitab 15 trial version) and MATLAB (R2010a trial version) were used for data analysis. The t-value and p-value indicate that the major impact factors include the interaction effect of solution pH value and reaction temperature (X(2)X(3)), the linear terms of acetone : formaldehyde molar ratio (X(1)), reaction time (X(4)) followed by the square effects of acetone/formaldehyde molar ratio (X(1)X(1)). The optimized results were achieved with the acetone: formaldehyde molar ratio (mol/mol) at 3:1, solution pH value at 6.0, reaction temperature at 70 degrees C, and reaction time at 140 min, respectively. This method can not only significantly reduce the number and cost of the tests, but also provide a good experimental design strategy for the development of furan resin. The investigation shows that the predicted results of 24 h tensile strength are consistent well with the experimental ones.