Published in:
Macromolecular Chemistry and Physics, 221 (2020) 5
Language:
English
DOI:
10.1002/macp.201900468
ISSN:
1521-3935;
1022-1352
Origination:
Footnote:
Description:
AbstractAmong odd‐nylons, nylon‐5 exhibits the highest remanent polarization and is thus a desirable material for many applications of ferroelectric polymers. However, nylon‐5 has never been used as a ferroelectric material, because the synthesis of nylon‐5 and its processing into thin films are challenging. This work revisits the synthesis of nylon‐5 via anionic ring opening polymerization (AROP) and studies the effect of reaction time and scale‐up on (i) molecular weight (Mn), (ii) melting point (Tm), (iii) yield, and (iv) ferroelectric properties. For the first time, the molecular weight of nylon‐5 is characterized via size exclusion chromatography (SEC), nuclear magnetic resonance (NMR) spectroscopy, as well as matrix assisted laser desorption ionization time of flight mass spectroscopy (MALDI ToF‐MS), showing Mn values of up to 12 500 g mol‐1. Extended reaction times and the synthesis on a larger scale increase the molecular weight and yield. Nylon‐5 thin films are fabricated from a TFA:acetone (60:40 mol%) solvent mixture. Nylon‐5 thin‐film capacitors are ferroelectric and show a remanent polarization as high as 12.5 ± 0.5 μC cm‐2, which is stable in time. The high remanent polarization values, combined with the facile solution processing, render nylon‐5 a promising candidate for future microelectronic and multi‐ferroic applications.