处理工艺对大豆蛋白基胶黏剂的影响

研究了交联改性前大豆蛋白基胶黏剂的NaHSO3改性处理工艺对大豆蛋白基胶黏剂性能的影响。结果表明：当反应温度为30℃、反应时间为0.5 h、加入4% NaHSO3处理大豆蛋白，再经交联剂改性制备的大豆蛋白基胶黏剂胶合板干、湿强度满足GB/T 9846.3-2004中有关I类胶合板的强度要求。动态热机械性能( DMA)分析结果表明， NaHSO3改性处理后大豆蛋白基胶黏剂的机械性能和热稳定性都有所提高，固化起始温度略降低。差示扫描量热( DSC)和傅里叶红外光谱( FTIR)分析表明，经NaHSO3处理后蛋白质分子中的二硫键有明显的断裂，且有明显的DSC固化放热峰。交联改性前，大豆蛋白通过NaHSO3改性处理，可以降低大豆蛋白基胶黏剂的交联剂使用量，从而在不影响使用性能的前提下，进一步降低大豆蛋白胶黏剂的制作成本。

Effects of soy protein treatment process on soy protein-based adhesives

Before cross-linker modifying soy-based adhesive, early treatment process of soy protein was conducted and studied. The results showed that when treating soy protein with NaHSO3 , the optimum condition would be: addition amount of NaHSO3 4% on solid content of soy protein, treating for 0. 5 h at the temperature 30 ℃. Then adding cross-linker, the dry and wet strength of plywood with soy-based adhesive could satisfy with the requirement of GB/T 9846.3-2004 for I type plywood. The dynamic mechanical thermal analysis ( DMA) indicated that soy protein treated by NaHSO3 had no obvious effects on the curing and thermal stability of soy-based adhesive, and the onset curing temperature of soy-based adhesive was lower than that of the un-treated by NaHSO3 . Differential scanning calorimetry ( DSC ) and Fourier transform infrared spectroscopy ( FTIR ) showed that disulfide bond of soy protein were broken and had obvious exothermic peak of DSC when treated by NaHSO3 . The main conclusions were as follows:before cross-linker modifying soy-based adhesive, soy protein treated by NaHSO3 could reduce the addition amount of cross-linker agent, to further reduce the production cost of soy protein-based adhesive.