To increase water resistance and bonding strength of urea-glyoxal (UG) resin as wood adhesive, using hyper-branched polyethyleneimine (HBPEI), urea (U) and glyoxal (G), a novel resin (HBPEIU-G) was designed and synthesized successfully. The HBPEI polymer was initially reacted with urea under heating condition without using extra catalyst, then glyoxal (40% aqueous solution) was directly added to it at molar ratio of 1.4:1. The structures of HBPEIU and performances of HBPEIU-G resin were distinguished when was applied as wood adhesive. The results of the prepared two-ply panels produced in laboratory showed that both dry and wet bonding strength of HBPEIU-G resin were far higher than that of the controlled UG resin. Especially, the wet bonding strength enhanced significantly from 0 MPa to 0.63 MPa. The results of electron spray ionization mass spectrometry (ESI–MS) and FTIR confirmed that the target products of HBPEIU polymer had been obtained and the chemical reaction between synthesized HBPEIU polymer and glyoxal have been occurred. In HBPEIU-G resin, the dominant oligomers were HBPEI branched polymer which offered enough network structures for excellent bonding strength. Meanwhile, the viscosity of HBPEIU-G resin was higher than that of the UG resin, and differential scanning calorimeter (DSC) analysis also indicated that the curing peak temperature of HBPEIU-G resin was much lower than that of the UG resin.

为提高作为木材胶粘剂的尿素-乙二醛（UG）树脂的耐水性和粘结强度，使用超支化聚乙烯亚胺（HBPEI）、尿素（U）和乙二醛（G），设计并合成了一种新型树脂（HBPEIU-G）成功地。HBPEI聚合物首先在加热条件下与尿素反应，不使用额外的催化剂，然后以1.4:1的摩尔比直接加入乙二醛（40%水溶液）。HBPEIU的结构和HBPEIU-G树脂在用作木材胶粘剂时表现出明显的差异。在实验室中制备的两层板的结果表明，HBPEIU-G树脂的干粘合强度和湿粘合强度均远高于受控的UG树脂。特别是，湿结合强度从 0 MPa 显着提高到 0.63 MPa。电子喷雾电离质谱(ESI-MS)和FTIR结果证实HBPEIU聚合物的目标产物已经获得，合成的HBPEIU聚合物与乙二醛发生了化学反应。在 HBPEIU-G 树脂中，主要的低聚物是 HBPEI 支化聚合物，它提供了足够的网络结构以实现优异的粘合强度。同时，HBPEIU-G树脂的粘度高于UG树脂，差示扫描量热仪（DSC）分析也表明HBPEIU-G树脂的固化峰值温度远低于UG树脂。主要的低聚物是 HBPEI 支化聚合物，它提供了足够的网络结构以实现出色的粘合强度。同时，HBPEIU-G树脂的粘度高于UG树脂，差示扫描量热仪（DSC）分析也表明HBPEIU-G树脂的固化峰值温度远低于UG树脂。主要的低聚物是 HBPEI 支化聚合物，它提供了足够的网络结构以实现出色的粘合强度。同时，HBPEIU-G树脂的粘度高于UG树脂，差示扫描量热仪（DSC）分析也表明HBPEIU-G树脂的固化峰值温度远低于UG树脂。