Modelling of resole-type phenol formaldehyde polymerisation in homogeneous, continuous-flow, stirred-tank reactors

Abstract

The polymerisation kinetics of resoles has been modelled and numerical results obtained for an isothermal, homogeneous, continuous-flow, stirred-tank reactor. The different reactivities of the ortho and para hydrogens on the phenolic rings, both at the 'ends' of polymeric chains as well as at the shielded 'internal' locations, have been accounted for in the kinetic model and a sensitivity analysis has been carried out. The concentrations of phenol, formaldehyde, various sites, branch points and the number-average chain length are obtained for various values of the rate constants, phenol to formaldehyde ratio in the feed stream and the average residence time in the reactor. It has been observed that the reactivity of the para-hydrogen atom on an 'end' phenolic ring is the most important parameter.