Tailoring fluorinated electroactive polymers toward specific applications

Introducing Photo-Cross-Linkable Functionalities on P(VDF-co-TrFE) Ferroelectric Copolymer

Ferroelectric polymers have emerged as crucial materials for the development of advanced organic electronic devices. Their recent high-end commercial applications as fingerprint sensors have only increased the amount of scientific interest around them. Despite an ever-larger body of studies focusing on optimizing the properties of ferroelectric polymers by physical means (e. g., annealing, stretching, blending or nano-structuring), post-polymerization chemical modification of such polymers has only recently become a field of active study with great promise in expanding the scope of those polymers. In this work, a solution-based post-polymerization modification method was developed for the safe and facile grafting of a plethora of functional groups to the backbone of commercially available Poly(vinylidene fluoride-co-trifluoroethylene P(VDF-co-TrFE) ferroelectric polymers. To showcase the versatility of this approach, photosensitive groups were grafted onto the polymeric backbone, enabling them to undergo photo-cross-linking. Finally, these modified polymers were used as functional negative photoresists in a photolithographic process, highlighting the potential of this method to integrate ferroelectric fluorinated electroactive polymers into standard electronic microfabrication production lines.

Chemical Structural Coherence Principle on Polymers for Better Adhesion

Composite materials are the most variative type of materials employed in almost every task imaginable. In the present study, a synthesis of a novel perfluoroalkyltriethoxysilane is reported to be used in creating composites with polyhexafluoropropylene—one of the most indifferent and adhesion-lacking polymers existing. The mechanism of adhesion of hexafluoropropylene is proved to be due to chemical structural coherence of perfluoroalkyltriethoxysilane to a link of polyhexafluoropropylene chain. The ability of perfluoroalkyltriethoxysilane to attach to surfaces was studied by FT-IR spectroscopy of modified glass microspheres. Although the perfluoroalkyltriethoxysilane surface modifier allowed partial adhesion of polyhexafluoropropylene, some detachment took place; therefore, the surface nanostructuring was used to increase its specific area by aluminum foil anodizing. An anodized aluminum surface was studied by scanning electron microscopy. The resulting composite consisting of anodized aluminum, perfluoroalkyl surface modifier, and polyhexafluoropropylene layer was proved to be stable, showed no signs of detachment, and is a promising material for usage in harsh environments.