Effect of hydrogen–deuterium exchange in amide linkages on properties of electrospun polyamide nanofibers.

The effect of deuteration of polymeric nanofibers (NFs) on their structure and thermal and mechanical properties was investigated. Three types of polyamides (PA; PA66, PA6, and PA11) NFs were prepared by electrospinning from solutions with non-deuterated or deuterated solvents and subsequently characterized. In the NFs prepared with deuterated solvents, partial hydrogen–deuterium (H–D) exchange occurred in the amide linkages of the polymers, leading to improved thermal and mechanical properties. Further, partial deuteration of amide linkages in all the PAs slightly increased the NF melting and glass transition points and substantially improved the Young's moduli and tensile strengths of the NF sheets by 1.2–1.3 times. Additionally, the degree of crystallinity improved due to the deuteration effect. The results clearly indicate that this facile, solution processing approach based on H–D exchange in the amide linkages is promising for improving the properties of polymer NFs. [Display omitted] • First report on ambient stable deuteration effect on polymeric nanofiber properties. • Facile hydrogen bond tuning in electrospun polyamide nanofibers. • Solution phase H–D exchange partially replaces H in the amide linkages with D. • Improved thermal and mechanical properties achieved for all polyamide nanofibers. [ABSTRACT FROM AUTHOR]