In order to reduce usage of formaldehyde content adhesives and popularize environment friendly adhesive application in plywood, the modified soy-based adhesive (SBA) was prepared as a new kind of waterproof adhesive to make plywood. The hot-press conditions were optimized by using orthogonal experimental design. The curing mechanism of soy-based adhesive was investigated by FTIR, XPS and TG-DTG. The results showed that (i) hot-press temperature, pressure and time could affect the bonding strength and the contribution order was hot-press temperature > hot-press pressure > hot-press time; (ii) under the optimized conditions (hot-press temperature 140℃, hot-press pressure 1.0 MPa and hot-press time 4.69 min), the water-resistant bonding strength of plywood was up to 0.91 MPa, which meets the requirement of plywood type II in GB/T 9846-2004. Fourier transform infrared spectroscopy (FTIR) analysis showed the SBA was crosslinked by chemical reaction during the curing process, the crosslinking gave rise to the increase of amino bonds and reduce of hydrophilic groups. X-ray photoelectron spectroscopy (XPS) analysis showed that during the curing process amide reaction occurred and accompanied with amination which induced the formation of 3D structure of SBA. And the TG-DTG results showed that SBA cured completely when the temperature was in the range of 140-150°C, above this range it could result in decomposition of SBA. The research can provide a reference for SBA application in plywood industry.%为了减少含甲醛胶黏剂和推广环境友好型胶黏剂在胶合板中的应用,该文对脱脂豆粉进行改性后制成具有耐水性的大豆胶黏剂,用于生产胶合板,分析了热压工艺对胶合板性能的影响；并辅以仪器分析结果阐述改性豆胶的固化机理.结果表明,热压工艺的影响因素大小排序为热压温度＞热压压力＞热压时间；较佳热压工艺为:140℃、1.0 MPa和4.69min,胶合板的耐水胶合强度(0.91 MPa)符合国家标准GB/T9846-2004中Ⅱ类胶合板的要求(≥0.80 MPa).傅里叶变换红外光谱分析表明,固化后的改性豆胶亲水性基团减少,酰胺键有所增加;豆胶在固化过程中内部基闭发生反应,形成交联.X-射线光电子能谱分析表明,改性豆胶固化过程不仅发生酰胺化反应,还发生胺化作用,使豆胶交联成体型结构.热重-微分热重分析表明,升温至140～150℃时,豆胶的吸附水和官能团间缩合反应产生的水分蒸发完毕,豆胶完全固化:继续升温,豆胶发生热分解.该研究可为豆胶的工业化应用提供参考.
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