The structure of polyamide 46/polyamide 6I copolymers obtained by reaction in the molten state is analyzed as a function of the extrusion time, the extrusion temperature, and the overall blend composition by 13 C NMR. The degree of transamidation, the degree of randomness, and the number-average block length of the copolymers are calculated using the method for a four-component polyamide system. It is shown that the transamidation processes are occurring very fast during the first period of melt-mixing but are slowing down at longer extrusion times. High extrusion temperatures affect the transamidation processes in an increasing way. From 13 C NMR experiments on PA 46/PA 6I copolymers with different compositions, differences in reactivities are observed. The change of the molecular structure of the copolyamides as a function of the processing conditions and the overall blend composition strongly affects their crystallization behavior.
No takes yet. Share an insight, caveat, or question.
Eersels et al. (1996) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: