Thermodynamics of lactam polymerization

A negative value of AGp for a lactam only indicates that polymerization is possible. Sometimes, such lactams do not polymerize because of the lack of a suitable reaction path, or they undergo other kinetically or thermodynamically more favoured reactions (see Section 8). 

Irrespective of the reaction mechanism, the polymerization of lactams leads to an equilibrium between monomer, cyclic oligomers and polymer. Tobolsky and Eisenberg [9] showed that the thermodynamic parameters are independent of the reaction mechanism, so that the polymerizability may be rationalized in terms of the ease of formation of the cyclic monomer, or, its opening into a linear chain unit. The simple relation between the equilibrium monomer concentration [L]e, temperature, and standard heat and entropy of polymerization. 

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