Modelling of phenolic resin polymerisation

Kinetics of hydroxymethyl phenols formation by in‐line FTIR spectroscopy

“…Values obtained in this work differ from those previously reported, especially for E a6 and E a7 . 13,18 The consumption of phenol and formaldehyde may be calculated from the kinetic model by using optimized kinetic parameters. The accuracy of the kinetic model was confirmed by comparing experi- mental concentration profiles of formaldehyde and phenol with the calculated ones (using the estimated kinetic parameters) for different molar ratios of phenol to formaldehyde 1/2 in 1/3 and 1 mol of NaOH at reaction temperatures of 308C, 408C, 508C in 608C, as well as for reactions with a molar ratios of phenol to formaldehide 1/2, 1/2.5 in 1/3 and with 0.1 mol; 0.5 mol in 0.8 mol of NaOH at the reaction temperature of 508C.…”

“…Recently, Manfredi et al 17 have presented the model of the synthesis of a resol-type phenolic resin at constant temperature and at constant pH value with different formaldehyde to phenol molar ratios. Riccardi et al 18 have applied the model of Manfredi et al 17 to study the influence of some of the other synthesis parameters on the kinetic scheme. Because of the lack of comprehensive information on phenol-formaldehyde reactions under very alkaline conditions in a wide range of pH values as well as in a wide range of temperatures and with different phenol to formaldehyde ratios, we chose to study the structural and kinetic differences between the prepolymers synthesized under different conditions.…”

The Chemical Batch Reactor

“…In recent years, a generalized procedure has been reported in [11,14] that allows one to build a detailed model for the synthesis of resol-type phenolic resins. This procedure is based on a group contribution method and virtually allows one to estimate the kinetic parameters of every possible reaction taking place in the system.…”

“…A second-order kinetics has been assumed [8,14] for all reactions included in the reaction mechanism, which is composed by the following 89 reactions:…”

“…Phenol (C 6 H 5 OH) and formaldehyde (CH 2 O) can react in different ways depending on the catalyst used and the initial formaldehyde-to-phenol molar ratio. In the production of resol-type phenolic resins, in the presence of an alkaline catalyst, the reactions occurring in the system can be classified into two main types, namely, reactions of addition of methylol groups to the aromatic ring and reactions of condensation of aromatic rings to form higher molecular weight components and, finally, polymers [14].…”