Fabrication of a Conjugated Fluoropolymer Film Using One-Step iCVD Process and its Mechanical Durability

Abstract

Most superhydrophobic surface fabrication techniques involve precise manufacturing process. We suggest initiated chemical vapor deposition (iCVD) as a novel CVD method to fabricate sufficiently durable superhydrophobic coating layers. The proposed method proceeds with the coating process at mild temperature (40 °C) with no need of pretreatment of the substrate surface; the pressure and temperature are optimized as process parameters. To obtain a durable superhydrophobic film, two polymeric layers are conjugated in a sequential deposition process. Specifically, 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane (V4D4) monomer is introduced to form an organosilicon layer (pV4D4) followed by fluoropolymer formation by introducing 1H, 1H, 2H, 2H-Perfluorodecyl methacrylate (PFDMA). There is a high probability of covalent bond formation at the interface between the two layers. Accordingly, the mechanical durability of the conjugated fluoropolymer film (pV4D4-PFDMA) is reinforced because of cross-linking. The superhydrophobic coating on soft substrates, such as tissue paper and cotton fabric, was successfully demonstrated, and its durability was assessed against the mechanical stress such as tensile loading and abrasion. The results from both tests confirm the improvement of mechanical durability of the obtained film.

Nanoscale control by chemically vapour-deposited polymers

“…123 Copolymerizing PFMDA with the tetravinyl organosilicone crosslinker V4D4, lead to films able to withstand >3000 cycles of abrasion testing. 124 Transparent and robust optical protection results from the iCVD copolymerization of PFDA with the epoxyfunctional monomer GMA. Annealing these films induces crosslink formation through the ring opening of epoxy groups.…”

Glucose-Responsive Boronic Acid Hydrogel Thin Films Obtained via Initiated Chemical Vapor Deposition

“…With iCVD, smart hydrogels responding to temperature, humidity, light, and pH were synthesized. − The great advantages of iCVD, compared to other vacuum-based deposition methods for organic compounds such as plasma-enhanced CVD or photoinduced CVD, are the mild process conditions resulting in a substantial retention of functional groups and a great variety of applicable substrates, such as tissue paper, pharmaceutics, optical microcavity probes, or even ionic liquids, − while on the contrary, for the monomer species, certain requirements need to be fulfilled. They need to be vaporizable and contain a vinyl (CC) bond, which will form the polymer backbone during the synthesis.…”

Fabrication of Transferable and Micro/Nanostructured Superhydrophobic Surfaces Using Demolding and iCVD Processes

“…To reduce dependence on complicated hierarchical surface structures and further improve the liquid repellency with high contact angles and low roll-off angles, a general strategy is to add micro/nanostructured roughness and then chemically modify it to produce a low-energy surface . For instance, initiated chemical vapor deposition (iCVD) is a facile, low-cost, scalable, and low-energy vapor deposition process that could produce nanoscale fluorinated polymeric films with low surface energy, such as 1H,1H,2H,2H-perfluorodecyl methacrylate (PFDMA), 1H,1H,2H,2H-perfluorodecyl acrylate (PFDA), and 1H,1H,2H,2H-perfluorooctyl acrylate (PFOA) in which these suspended chemical moieties remain intact . Compared to other surface modification techniques, such as spray coating, , and sol–gel processing, this process without solvent participation is environmentally friendly.…”