【作者】 赵佳宁；

【导师】 顾继友；

【作者基本信息】 东北林业大学 ， 木材科学与技术， 2007， 硕士

【摘要】 我国目前脲醛树脂(UF树脂)合成工艺主要是传统碱-酸-碱合成工艺，并且在此工艺基础上使用三聚氰胺改性脲醛树脂(MUF树脂)，以提高其耐水性和防潮性。但是碱-酸-碱合成工艺只能通过降低F／U和F／(M+U)摩尔比或者加入改性剂，提高脲醛树脂和MUF树脂性能，减少其板材甲醛释放量。随着化工原料价格上涨，这种靠降低F／U和F／(M+U)摩尔比或者加入改性剂方法，不具备成本优势。因此，研究一种能在较高F／U和F／(M+U)摩尔比下，树脂和板材性能也能达到国家标准的新合成工艺对于脲醛树脂合成及人造板生产企业都具有重要意义。本论文通过研究不同弱酸性条件下合成脲醛树脂工艺，对弱酸性条件下合成脲醛树脂工艺特点和树脂性能有了进一步了解。在此基础之上确定了弱酸性起始合成脲醛树脂工艺，并使用方差分析方法对弱酸性起始合成脲醛树脂工艺进行优化设计。再此工艺基础之上，利用三聚氰胺对脲醛树脂进行改性，生产MUF树脂及其胶合板性能完全达到GB／T9846.7-2004标准。同时，在不同固化剂下，对弱酸性条件下起始合成脲醛树脂固化进行研究。优化出一种具有优越性能的、低成本的固化剂。论文利用现代仪器分析方法(DSC、傅立叶红外光谱仪和紫外分光光度计)和化学分析方法对脲醛树脂和MUF树脂的化学基团、官能团、树脂固化、及胶合板甲醛释放规律进行了较详细研究。在F／U最终摩尔比相同情况下，弱酸性起始合成的脲醛树脂亚甲基和醚键含量高于普通脲醛树脂，但其甲醛释放量低于普通脲醛树脂。弱酸性起始合成MUF树脂，在M／U摩尔比较高情况下，胶合板性能达到国家标准。不同固化剂对同一种弱酸性起始合成的脲醛树脂固化效果不同，其胶合板胶合强度和甲醛释放能力也不同。研究结果揭示了弱酸性起始合成脲醛树脂工艺的反应特点和固化树脂特性，对弱酸性条件下合成脲醛树脂工艺有一定指导作用。更多还原

【Abstract】 At present, the technique of UF resin is mainly the traditional synthetic technique ofbasic-acidic-basic. UF resin is modified with melamine by the traditional synthetic techniqueof basic-acidic-basic to improve the resist of water and moister of UF resin. However, thesynthetic technique of basic-acidic-basic is only to decrease the mole ratio of F/U or F/(M+U)and to add to modifiers which are used to improve the quality of UF and MUF resin and lowthe formaldehyde emission with the chemical price growing, the means which decrease themole ratio of F/U or F/(M+U) and add to modifiers are not advantage of cost. So the newsynthetic technique is studied at high the mole ratio of F/U or F/(M+U) and the quality of resinand board to reach to the standard of government. This is important meaning to the syntheticUF resin and board of enterprise.With studying on the synthetic technique of UF resin with different weak acidity, thecharacteristic of synthetic technique and the quality of it was understood. The synthetictechnique of UF resin with initial weak acidity condition was ascertained. By using theorthogonal test, the results were analyzed by variance analysis, and the optimum for synthesisUF resin finally was found. UF resin is modified by melamine with the synthetic technique ofUF resin with initial weak acidity condition. The quality of MUF resin and plywood whichwere made of MUF resin reached the standard of GB/T9846.7-2004. Aslo, with differentcuring agent the curing procedure of UF resin which was synthesized under initial weak aciditycondition was studied. One kind of good properties, low cost curing agent cost was concluded.The chemical group, functional group, resin curing and the rule of formaldehyde emissionof plywood were studied by DSC, FTIR and UV in details.When the mole ratio of F/U is the same as common UF resin, the amount of methyleneand aether bond in UF resin which was synthesized under initial weak acidity condition wasmore than common UF resin. The Formaldehyde emission of UF resin of plywood lower thancommon plywood. At higher the mole ratio of M/U, the quality of MUF rein and the propertiesof plywood could reach to the requirement of government. The curing effect of different curingagent is different to UF resin. The formaldehyde emission and bond strength of plywood isdifferent, too. The results showed the characteristic reaction of synthetic technique of UF resinwith initial weak acidity condition and cured UF resin. It has practical function on applicationof synthetic technique of UF resin with weak acidity condition.更多还原