RT Journal Article
T1 Organic-acid mediated bulk polymerization of ε-caprolactam and its copolymerization with ε-caprolactone
A1 Sanchez-Sanchez, Ana
A1 Basterretxea, Andere
A1 Mantione, Daniele
A1 Etxeberria, Agustin
A1 Elizetxea, Cristina
A1 de la Calle, Amaia
A1 García-Arrieta, Sonia
A1 Sardon, Haritz
A1 Mecerreyes, David
AB Polyamides (PA) constitute one of the most important classes of polymeric materials and have gained strong position in different areas, such as textiles, fibers, and construction materials. Whereas most PA are synthesized by step-growth polycondensation, PA 6 is synthesized by ring opening polymerization (ROP) of ε-caprolactam (ε-CLa). The most popular ROP methods involve the use of alkaline metal catalyst difficult to handle at large scale. In this article, we propose the use of organic acids for the ROP of ε-CLa in bulk at 180 °C (below the polymer's melting point). Among evaluated organic acids, sulfonic acids were found to be the most effective for the polymerization of ε-CLa, being the Brønsted acid ionic liquid: 1-(4-sulfobutyl)−3-methylimidazolium hydrogen sulfate the most suitable due to its higher thermal stability. End-group analysis by 1H nuclear magnetic resonance and model reactions provided mechanistic insights and suggested that the catalytic activity of sulfonic acids was a function of not only the acid strength, but of the nucleophilic character of conjugate base as well. Finally, the ability of sulfonic acid to promote the copolymerization of ε-CLa and ε-caprolactone is demonstrated. As a result, poly(ε-caprolactam-co-ε-caprolactone) copolymers with considerably randomness are obtained. This benign route allows the synthesis of poly(ester amide)s with different thermal and mechanical properties.
SN 0887-624X
YR 2016
FD 2016-08-01
LK https://hdl.handle.net/11556/3214
UL https://hdl.handle.net/11556/3214
LA eng
NO Sanchez-Sanchez , A , Basterretxea , A , Mantione , D , Etxeberria , A , Elizetxea , C , de la Calle , A , García-Arrieta , S , Sardon , H & Mecerreyes , D 2016 , ' Organic-acid mediated bulk polymerization of ε-caprolactam and its copolymerization with ε-caprolactone ' , Journal of Polymer Science, Part A: Polymer Chemistry , vol. 54 , no. 15 , pp. 2394-2402 . https://doi.org/10.1002/pola.28114
NO Publisher Copyright: © 2016 Wiley Periodicals, Inc.
NO The authors acknowledge the financial support of Euskampus Fundazioa, the Spanish Ministery of Economy and Competition through project CTQ2014-53458-1 and the European Commission through project SUSPOL-EJD 642671 and FP7-PEOPLE-212-ITN 316832-OLIMPIA (D. Mantione). Haritz Sardon gratefully acknowledges financial support from MINECO through project FDI 16507. A. Sanchez-Sanchez thanks “Convocatoria de Contratación para la especialización de personal investigador doctor en la UPV/EHU” for financial support. The SGIKER UPV/EHU for the NMR facilities of Gipuzkoa campus are acknowledged.
DS TECNALIA Publications
RD 29 jul 2024