Polycaproamide anionic

Modelling non-isothermal crystallization is the next important step in a quantitative description of reactive processing. This is particularly important, because crystallization determines the properties of the end product. Therefore, the development the spatial distribution of crystallinity, a, and temperature, T, with time throughout the volume of the reactive medium must be calculated. It is also noteworthy that crystallization and polymerization processes may occur simultaneously. This happens when polymerization proceeds at temperatures below the melting point of the newly formed polymer. A typical example of this phenomenon is anionic-activated polymerization of e-caprolactam, which takes place below the melting temperature of polycaproamide. 

Figure 4.40. A model reactor for front polymerization in the synthesis of slabs from "anionic" polycaproamide.

It can be shown that three different modes of front propagation during the formation of polycaproamide can be observed, depending on the relationship between the process parameters. In the first mode, which was found experimentally, the zones of polymerization and crystallization coincide. In the second mode these zones are separated in space. The third mode, which was predicted theoretically, is characterized by a non-monotonic distribution of the degree of crystallinity. However, it is not clear whether this situation can actually be observed in anionic e-caprolactam polymerization because even slight variations in parameters transfers the system into another regime. 

Alfonso, G.C. Costa, G. Pasolini, M. Russo, S. Ballistreri, A. Montaudo, G. Puglisi, C. Flame-resistant polycaproamide by anionic pol3merization of e-caprolactam in the presence of suitable flame-retardant agents. 7. Appl. Polym. Sci. 1986, 31, 1373-1382. 

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