9.4 Kinetic Under Equilibrium Consideration k1is the same as kp; and k2is the rate constant of depolymerizationk2k1+ H2OOOn HO-R-OH + n HOOC-R'-COOHO-C-R-O-C-R'-CWe must remove the by-product of the forward polymerization reaction so as to drive the equilibrium toward high molecular weight polymer. It can be removed by a combination of temperature, reduced pressure and purging with inert gas. Driving an equilibrium toward polymer requires considerable effort, since the by-product molecules must diffuse through and out of the viscous reaction mixture. Many condensation polymerization become diffusion-controlled by the rate of diffusion of small molecule by-
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