26 сентября, 2015 
Malyar A real concondensation between phenol and urea can be performed in three ways: Reaction of methylolphenols with urea [166-169].
Acidic reaction of urea-formaldehyde concentrate (UFC) with phenol followed by an alkaline reaction [170,171].
Reaction exclusively under alkaline conditions of urea and phenol in competition with each other leading to reaction of methylol ureas with phenol and PF oligomers, and to reactions of methylolphenols with each other, as well as reactions of methylolphenols with urea [117,172]
The kinetics of the cocondensation of monomethylolphenol model compounds and urea under alkaline conditions is reported by Pizzi et al. [173] and Yoshida et al. [174]. The same kinetics but under acidic conditions is described by Tomita and Hse [166,170,175]. The interaction of esters and copolymerized urea on the fast advancement and hardening acceleration of low condensation alkaline PUF resins is reported by Zhao et al. [117,172].
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