工艺条件对制备改性脲醛树脂浆料中的甲醛含量的影响

The Influence of the Technological Conditions on Formaldehyde Content of Modified Urea-Formaldehyde Resin Slurry

摘要: 本实验采用羟甲基松香与脲醛共聚合，旨在减少脲醛树脂分子结构中可降解或分解生成甲醛的结构单元，从而有效地降低脲醛树脂浆料中甲醛的释放，制得低甲醛环保型改性脲醛树脂浆料。实验中对不同的酸性催化剂、碱性调节剂、甲醛/尿素投料比、硫脲的添加量等工艺条件下所制得的不同批次的脲醛树脂浆料中甲醛含量和固含量进行测定，筛选出最优工艺条件。实验所制得的脲醛树脂浆料为乳浊液，颜色呈淡黄色，固含量>40%，游离甲醛为1.09%，pH值6.8~7.2，固化时间超过30 d。

Abstract: The urea-formaldehyde resin (UFR) slurry is prepared by the copolymerization of modified hydroxymethyl rosin with urea and formaldehyde. In order to reduce the release of free formaldehyde efficiently, the approaches of the degradation and decomposition of UFR structural unit of formaldehyde are constructed, and then the environmental friendly modified urea-formaldehyde resin slurry with low-formaldehyde content is obtained. In the experiment, the optimal technological conditions through the determination of formaldehyde content and solids content of different batches of UFR slurry are selected by the different conditions such as acid catalyst, basic containing agent, ratio of urea and formaldehyde, and additional content of thiourea. The title product UFR slurry presents emulsion, faint yellow, solids content over 40%, free formaldehyde content 1.09%, pH 6.8 - 7.2, and solidification time over 30 days.