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 (℃) and reaction time (min) were considered in the experiments.U13(134) 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 (X2X3),the linear terms of acetone:formaldehyde molar ratio (X1),reaction time (X4) followed by the square effects of acetone/formaldehyde molar ratio (X1X1).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℃,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.

有机酯硬化剂对水玻璃砂的影响

通过正交试验分析了水玻璃的加入量增加和有机酯的加入对水玻璃砂的残留强度和24 h终强度的影响程度大小,结果表明:有机酯的加入使水玻璃砂的24 h终强度达到了普通水玻璃砂的要求;水玻璃加入量的减少,使有机酯硬化水玻璃砂的溃散性有较大提高。

生物质材料改性呋喃树脂的研究

采用不同生物质材料对脲醛呋喃树脂进行改性,主要通过24 h强度、外观、粘度等结果表征来衡量改性作用效果。结果表明,木质素改性会降低树脂强度,但去除游离甲醛效果突出;在一定范围内,腰果酚及葡萄糖改性均有利于提高树脂强度,但葡萄糖的转化率较低,容易出现树脂不溶物。