Polyesterification self-catalysed

Table 3 lists determined third-order rate coefficients for self-catalysed esterifications and polyesterifications. 

Self Catalysed Polyesterification Reactions (Without Catalyst)... 

The mechanism of self catalysed polyesterification is described by the following four classical equilibrium reactions (reactions 8.7-8.10). 

The mechanism of the acid-catalysed (AH = acid catalyst) polyesterification reaction (for example using para toluenesulfonic acid as the catalyst) is presented in the following equilibrium reactions (8.11-8.14). The mechanism is very similar to those of the self catalysed polyesterifications. 

In principle, the mechanism of acid catalysed polyesterification is similar to the mechanism of self catalysed polyesterification with the difference that the acidic carboxyl group used as catalyst is replaced by a strong acidic catalyst (AH). 

Certain step polymerizations are self-catalysed, i.e. one of the types of functional group also acts as a catalyst (e.g. carboxylic acid groups in a polyesterification). In the absence of an added catalyst the rate of reaction for such polymerizations is given by... 

For a consideration of more strictly kinetic aspects of polyesterification by direct esterification, it is convenient to discuss separately the cases of self-catalysis and catalysed esterification. 

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