Uron結(jié)構降低脲醛樹脂游離甲醛含量及膠接膠合板

摘要：論文制備了含Uron結(jié)構的脲醛樹脂（Uron樹脂），并將其與普通脲醛樹脂在一定條件下混合，得到各種混合脲醛樹脂。通過混合脲醛樹脂固化速度測定、游離甲醛含量測定、膠合板制造及其甲醛釋放量與膠合強度測定、13C核磁共振分析等實驗，研究了Uron結(jié)構及其含量對降低脲醛樹脂游離甲醛含量及膠接膠合板甲醛釋放量等的作用與效果。結(jié)果表明：1）Uron結(jié)構對混合脲醛樹脂游離甲醛含量及膠接膠合板的甲醛釋放量都有明顯的降低作用，前者最大可達76%，后者最大可達84%；2）Uron樹脂的制備時間可以減少至8小時； 3）Uron樹脂與脲醛樹脂的比例為20:100時，混合脲醛樹脂具有較好的綜合理化性能。
關鍵詞：Uron；脲醛樹脂膠粘劑；游離甲醛；13C核磁共振

Three types of uron resin which contains much more uron cycle structure were prepared, and several mixed urea-formaldehyde (UF) resins were obtained by mixing uron resins with normal UF resins in this paper. The effects of uron structure and its amount on reducing free formaldehyde content of UF resins and  formaldehyde emission value of its bonded plywood were studied by testing the curing time, free formaldehyde content of the resin, manufacturing plywood, testing free formaldehyde emission level, and bonding strength of the plywood, and analyzing 13C-NMR spectrum of the resins. The results indicate that: 1) The Uron resins can distinctly reduce free formaldehyde content and emission level of UF resin and its bonded plywood, the former can be reduced to 76% and the latter to 84%; 2) The manufacturing time of uron resin can be shortened to 8 hours; 3) The mixed UF resins with 20% uron resin have a relatively perfect performance.
Key word: Uron resin; urea-formaldehyde resin; free formaldehyde; 13C-NMR