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A method for the preparation of an improved urea - the form of aldehyde resin, the urea - formaldehyde resin and its use for the production
A method for the preparation of an improved urea - the form of aldehyde resin, the urea - formaldehyde resin and its use for the production
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机译:一种制备改进的脲醛树脂的方法,脲醛树脂及其在生产中的用途
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摘要
In the first stage of the process, 1.8-2.2 moles of HCHO are reacted with 1 mole of urea at b.pt. and pH 4.8-5.0 and in the second stage, urea is added to give the desired U/F ratio, specif. 1-1.5, at temp b.pt. and pH 5-5.2. HCHO content of the compsn is very low and free HCHO is not generated during compression of wood panels in the course of mfr.
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