Polyvinylidene Fluoride Aerogels with Tailorable Crystalline Phase Composition

oleh: Jorge Torres-Rodriguez, Diana E. Bedolla, Francesco D’Amico, Ann-Kathrin Koopmann, Lisa Vaccari, Giulia Saccomano, Richard Kohns, Nicola Huesing

Format: Article
Diterbitkan: MDPI AG 2022-11-01

Deskripsi

In this work, polyvinylidene fluoride (PVDF) aerogels with a tailorable phase composition were prepared by following the crystallization-induced gelation principle. A series of PVDF wet gels (5 to 12 wt.%) were prepared from either PVDF–DMF solutions or a mixture of DMF and ethanol as non-solvent. The effects of the non-solvent concentration on the crystalline composition of the PVDF aerogels were thoroughly investigated. It was found that the nucleating role of ethanol can be adjusted to produce low-density PVDF aerogels, whereas the changes in composition by the addition of small amounts of water to the solution promote the stabilization of the valuable β and γ phases. These phases of the aerogels were monitored by FTIR and Raman spectroscopies. Furthermore, the crystallization process was followed by in-time and in situ ATR–FTIR spectroscopy. The obtained aerogels displayed specific surface areas > 150 m<sup>2</sup> g<sup>−1</sup>, with variable particle morphologies that are dependent on the non-solvent composition, as observed by using SEM and Synchrotron Radiation Computed micro-Tomography (SR-μCT).