Low-ether-bond-content urea-formaldehyde resin wood adhesive and preparation method thereof  

Inventor(s)（發明人）: LI TAOHONG; DU GUANBEN; GUO XIAOSHEN; LIANG JIANKUN; LEI HONG +

Priority number(s)（專利檢索號）: CN20141637847 20141113

Abstract of  CN105646808 (A)：

The present invention relates to a low-ether-bond-content urea-formaldehyde resin (UF) wood adhesive and a preparation method thereof, and belongs to the technical field of wood processing and production. The adhesive is synthesized through an addition-condensation polymerization reaction of urea (U) and formaldehyde (F) under a special condition, and is mainly characterized in that the ether bond content in the urea-formaldehyde resin structure is significantly reduced compared to the traditional urea-formaldehyde resin, and the methylene ether bond content accounts for 5-10% or less of the total amount of the aldehyde carbon. The preparation method is mainly characterized in that formaldehyde is added in twice, wherein one part of the urea and one part of the formaldehyde are added at the initial stage of the reaction and a molar ratio of the formaldehyde to the urea (F/U) is controlled at less than or equal to 1.6, and the other part of the formaldehyde is added at the middle stage of the reaction, and the other part of the urea is added after the reaction is performed for a certain time. According to the present invention, the low-ether-bond-content urea-formaldehyde resin (UF) wood adhesive has advantages of low ether bond content, good water resistance, rapid curing, and the like, is used for production of wood-based panels, especially plywoods, particle boards, medium density fiberboards, block boards and the like, and can effectively control the formaldehyde release during the use process.