Processing of polyamides in the presence of water via hydrophobic hydration and ionic interactions

Jules A.W. Harings, Yogesh S. Deshmukh, Michael Ryan Hansen, Robert Graf, Sanjay Rastogi

Research output: Contribution to journalArticlepeer-review

22 Scopus citations


In synthetic as well as natural polyamides, hydrogen bonding and conformations of amide motifs are strongly influenced by the presence of ions and their concentration, water molecules, and their structure, as well as the pH of the solution. This concept combined with solubility of synthetic aliphatic polyamides, in particular nylons, in water at elevated temperature and corresponding vapor pressure is evaluated as a new reversible shielding route in the processing of these polymers. So far, reversible shielding has not been feasible due to a lack in controlling desired activation and deactivation of hydrogen bonding at the judicious moments. Here we show that in the presence of large halogen anions, crystallization from the random coil state is suppressed by hydrophobic hydration, where the amorphous state of the fast crystallizing nylons can be maintained even at 20 °C. Small hydrating lithium cations are favored since they strengthen the hydrophobic nature of the anions. Complete deshielding of hydrogen bonding, after processing, is facilitated by simple migration of ions in water that allows recovery of the desired conformation and structure. © 2012 American Chemical Society.
Original languageEnglish (US)
Pages (from-to)5789-5797
Number of pages9
Issue number14
StatePublished - Jul 24 2012

Bibliographical note

Generated from Scopus record by KAUST IRTS on 2021-02-16


Dive into the research topics of 'Processing of polyamides in the presence of water via hydrophobic hydration and ionic interactions'. Together they form a unique fingerprint.

Cite this