The kinetic modeling of consecutive reactions in the controlled process
of step-growth polyaddition of diisocyanates to polyols
Polimery 2002, No 2, 77
The REAKTOR subroutine verified in earlier studies , was used to simulate several polyaddition reactions between diisocyanates and polyols yielding linear polyurethanes (PUR) (eqn. 2). Optimum reaction time and temperature were established for the step-growth polyadditions of toluylene diisocyanate (TDI) to 1,4-butanediol or to oligooxyethylene glycols (M = 200, 600 and 1000), which were run with either the macrodiol or TDI used in excess. The Mn of PUR and the number of steps were studied in relation to initial reactants concentrations and mole ratios and substitutent type in TDI diisocyanates. The growth of Mn of PUR was monitored in the individual steps of the polyaddition reactions involving various macrodiols (Figs. 6— 8). Temperature simulations allowed to establish the optimum reaction time to yield a PUR of maximum possible Mn.
Keywords: polyaddition of diisocyanates to diols, linear polyurethanes, model of step-growth polyaddition, temperature simulations, REAKTOR subroutine