By means of phenol liquefaction ( or phenolation) in the presence of sulfuric/phosphoric acids as catalyst, the soy flour translated into raw material for water-resistant wood adhesive. The techniques of GPC, HPLC, FTIR and plywood evaluation were employed to characterize the phenolated soy flours ( PSF) and the PSF-formaldehyde ( PSFF) adhesives. It indicated that more than 90% of soy flour translated into phenolated resultants with molecular weight ranged 250 -7 250 after the soy flour liquefied at 130 - 150 'C for90min with phenol/soy flour ratio ranged from 3/1 to 2/1, and some phenol was bonded to soy flour via 1 ,4- and 1,2- substitutions after liquefaction. Phenolation not only unfolded the globular structure of soy protein but also increased the quantity of reactive groups in PSF, therefore a low-free-formaldehyde adhesive with good bond strength and water resistance was prepared with PSF. The plywood panels manufactured with the PSFF adhesives resulted in 28 h boiling-dry-boiling wet bond strength from 1. 24 to 1. 81 Mpa. The phenol/soy flour ratio had various effects on the many properties of phenolated soy flour and PSFF adhesives, and the PSFF adhesive prepared with phenol/soy flour ratio of 3 had the best bond strength.%以硫酸/磷酸为催化剂和苯酚液化,将大豆粉转化为胶黏剂的制备原料,并制备得到耐水性木材胶黏剂.采用GPC,HPLC,FTIR等手段结合胶合板压制,对豆粉苯酚液化产物及其与甲醛缩聚得到的胶黏剂进行表征.结果表明:以苯酚/豆粉质量比为3/1～2/1、5%硫酸为催化剂下,将豆粉在130～150℃下液化90 min,90%以上的豆粉转化成相对分子质量为250～7250的产物,部分苯酚以1,4-取代和1,2-取代方式与豆粉反应形成结合酚;苯酚液化不仅破坏大豆蛋白的紧密球形结构,还使液化豆粉的活性基团增加,由此通过苯酚液化豆粉与甲醛缩聚,制得低游离甲醛释放的、胶接性能满足国家标准要求的Ⅰ类胶黏剂,由此所制备胶合板的28h煮-烘-煮湿强度在1.24～1.81MPa之间,达到耐候胶合板要求;苯酚/豆粉的比例对液化产物以及苯酚液化豆粉/甲醛胶黏剂的许多特性都有不同的影响,其中以苯酚/豆粉比例为3的胶黏剂胶接强度最好.
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