| 摘要 |
polymer production. SUBSTANCE: resin is prepared by condensation of urea, formaldehyde, and modifying agent in media with variable acidity followed by after-condensation with additional portion of urea, cooling, and stabilization of resin. According to invention, modifying agent is tetrafunctional cyclic amide of formula I: (I), which is added to reaction mixture after urea/formaldehyde condensation is completed in amount 0.0075 to 0.03 mol per 1 mol of urea. EFFECT: reduced toxicity of resin allowing fabrication of board material with formaldehyde emission not exceeding 5 mg/100 g. 3 cl, 1 tbl, 5 ex
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