Thermal properties of poly-ε-caprolactam and copolyamides based on ε-caprolactam

  • M. Krištofič
  • A. Ujhelyiová


The copolyamides consisting of ε-caprolactam and 6.1–24.5 wt.% of nylon salt prepared from adipic acid and 1-(2-aminoethyl) piperazine were synthesized. Physical and thermal characteristics of polyamide 6 and the copolyamides were compared. Nylon salt does not influence the polyreaction equilibrium so it is possible to prepare the copolyamides with high molecular weight and with the content of low-molecular compounds comparable with that of pure PA 6. Melting temperatures of the copolyamides are lower in comparison with PA 6 and decrease proportionally to the amount of the nylon salt. The thermal stability of the copolyamides is good and equal to that of PA 6. The melting enthalpies indicate that the process of crystallization of the copolyamides is influenced by the time of crystallization and the amount of comonomer present. Longer time of the crystallization assures higher degree of crystallization. The kinetics and the level of crystallization are positively influenced by the mobility of copolyamide segments mainly up to 10 wt.% of comonomer.


ε-Caprolactam Adipic acid 1-(2-Aminoethyl) piperazine Copolyamides Thermal properties 



This work was supported by the Slovak Research and Development Agency under the contract No. 20-011404 and VEGA Agency under the contract 1/4456/07


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© Akadémiai Kiadó, Budapest, Hungary 2009

Authors and Affiliations

  1. 1.Faculty of Chemical and Food TechnologySlovak University of Technology in BratislavaBratislavaSlovak Republic

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