In Chapter 2, it was assumed that the functional groups of the various oligomers have the same reactivity, independent of the chain length, n, of the molecules on which they are located. Mathematical results derived for step growth polymerization based on the equal reactivity hypothesis were subsequently used to explain the gross kinetic features of the polyesterification of adipic acid with ethylene glycol. Comparison with experimental data sufficiently indicated that the overall polymerization is far more complex and the assumption of the equal reactivity hypothesis is a considerable simplification. This is true not only for polyesterification, but for most step growth polymerization systems.1 In addition, as the polymerization progresses, the viscosity of the reaction mass increases by severalfold and the overall reaction, at some stage depending upon the reactor used, becomes mass transfer controlled.2–5 In diffusion controlled reactions, the method of reactor analysis is quite different and will be discussed in Chapter 5.
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- Linear Step Growth Polymerization Violating the Equal Reactivity Hypothesis
Santosh K. Gupta
- Springer US
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