Kinetics oligo-polyols

In Figure 3.11, one observes the kinetic curves of the oligo-polyol reaction, having only secondary hydroxyl groups compared to oligo-polyols having primary and secondary hydroxyl groups. 

Figure 3.11 Graphical representation of second order kinetics of the oligo-polyols reaction with different primary hydroxyl contents with phthalic anhydride, a initial concentration of phthalic anhydride b initial concentration of hydroxyl groups t time for total consumption of primary hydroxyl x concentration of a or b reacted at time t. Temperature 30 °C Solvent pyridine...

A reliable method to determine the oligo-polyol reactivity is the study of the kinetics of the oligo-polyol s reaction with phenyl isocyanate, a model for the -NCO groups of toluene diisocyanate (TDI) or diphenylmethane diisocyanate (MDI) ... 

The advantage of using phenyl isocyanate is that it is possible to develop the reaction kinetics until 100% conversion, without gelation. Obviously the results are relative, but it is possible to determine the relative order of reactivity between two or three oligo-polyols [35]. 

Figure 3.13 shows the reaction kinetics curves (conversion against time) of the phenyl isocyanate reaction with oligo-polyols having various percentages of primary hydroxyls. 

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See also in sourсe #XX -- [ , , , ]

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