Synthesis continued phenolic resin

Kinetic Study of the Phenolysis Reaction. With the demonstration that all of the already outlined deficiencies of ammonium lignin sulfonates as a phenol replacement can be reduced by phenolysis, attention was turned to consideration of the construction of a pilot plant scale continuous tube reactor. This is needed in order to prepare the large amounts of phenolyzed lignin sulfonates required for resin synthesis and testing under plywood production conditions. 

Numerous studies concerning O-alkylation of phenol were reported (refs. 3-9). Described catalysts belong to all the catalyst families oxides (ref. 3) phosphates (refs. 4, 5) metallosilicates (ref. 6) aluminophosphates (ref. 7) ion exchange resin (ref. 8). On the other hand, the selective mono-O-alkylation of diphenols was little reported and mainly in patent literature (ref. 9). The main studies deal with synthesis of guaiacol by methylation of 1-2-dihydroxybenzene 2 (catechol) (eqn. 1) catalyzed by boronphosphate eventually doped or supported (ref. 9). The main difficulties of this reaction consists in physical instability of the catalyst which is eluted in the reaction stream conducting to the formation of methylborate as a byproduct which has to be separated. It is then needed to add some new catalyst continuously. 

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