Controlling perfluoropolyalkylether rearrangements at the surface of photocured networks. (December 2019)

• Record Type: Journal Article
• Authors: Trusiano, Giuseppe; Vitale, Alessandra; Rizzello, Melania; Bonneaud, Céline; Joly-Duhamel, Christine; Friesen, Chadron M.; Bongiovanni, Roberta
• Is Part Of: European polymer journal. Volume 121(2019)
• Publication Date: 2019-12
• Subjects: Surface rearrangements -- Perfluoropolyalkylethers -- UV-curing -- Wettability control -- Hydrophobic polymers; Polymers -- Periodicals; Polymerization -- Periodicals; Polymères -- Périodiques; Polymérisation -- Périodiques; Polymerization; Polymers; Periodicals; Electronic journals; 547.705
• DOI: 10.1016/j.eurpolymj.2019.109285
• Languages: English
• ISSNs: 0014-3057

Abstract

Graphical abstract: Highlights: Perfluoropolyalkylethers are used as surface modifier in UV-curing of an epoxy resin. Fluoroadditives can rearrange if exposed to liquids causing a loss in performances. The matrix stiffness, the fluorinated chain length and functionality are tuned. The environmentally induced surface rearrangements of fluoroadditives are inhibited. Photocured polymer films with stable hydro/oleophobicity are obtained. Abstract: Perfluoropolyalkylether (PFPAE) reactive macromers can be used in very low concentration (≤2 wt%) as efficient surface modifying agents of epoxy resins to obtain hydrophobic photocured copolymers. However, the hydrophobicity achieved thanks to the spontaneous migration of the PFPAE chains to the free surface could be dramatically lost due to environmentally induced rearrangements of the fluorinated segments, even though they are chemically bonded to the polymer matrix. To preserve the coating performances of the photocured copolymers when exposed to various environments, different approaches have been investigated. In particular, to hinder the mobility of the fluorinated chains, the length of the fluorinated comonomer chain, the epoxy matrix stiffness, and the functional PFPAE end-groups have been tuned. Such strategies are demonstrated to inhibit or completely suppress the surface reconstruction of the copolymers when exposed to different surrounding environments (e.g., immersion in water or oil), allowing to obtain photocured films with a long-term and constant reduced surface energy of ≈20 mN/m.