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采用自制的可溶性三聚氰胺-甲醛低聚物作为脲醛树脂的添加剂,通过DSC及压制胶合板等方法评价该低聚物对脲醛树脂的固化特性、游离甲醛释放量和胶合强度的影响。结果表明,对于nF/nU为1.1的脲醛树脂UF1,随着三聚氰胺-甲醛低聚物加入量的增加,树脂固化活化能和胶合板的甲醛释放量都呈现先降低后增加的趋势,而胶合强度变化趋势不明显。对于nF/nU为1.2的脲醛树脂UF2,随着三聚氰胺-甲醛低聚物加入量的增多,树脂固化活化能先增加后降低;胶合板甲醛释放量逐渐降低;干强度变化趋势不明显,湿强度先降低后增加。方差分析表明,脲醛树脂的物质量比对胶合板性能的影响更为明显。
The self-made soluble melamine-formaldehyde oligomer was used as the additive of urea-formaldehyde resin. The effects of the oligomer on the curing properties of urea-formaldehyde resin, free formaldehyde emission and adhesive strength were evaluated by DSC and plywood compression. The results showed that for UF1 with nF / nU of 1.1, the curing activation energy and formaldehyde emission of plywood tended to decrease first and then increase with the addition of melamine-formaldehyde oligomer, while the bonding strength The trend is not obvious. For the urea formaldehyde resin UF2 with nF / nU of 1.2, the curing activation energy of resin increased first and then decreased with the addition of melamine-formaldehyde oligomer. The formaldehyde emission of plywood decreased gradually. The trend of dry strength did not change obviously. Lower after the increase. Variance analysis shows that the effect of urea-formaldehyde resin content on plywood performance is more obvious.