Photochemically Cross-Linked Perfluoropolyether-Based Elastomers: Synthesis, Physical Characterization, and Biofouling Evaluation

Abstract

A series of reactive liquid perfluoropolyether (PFPE) precursors were synthesized which can be photochemically cross-linked (UV-cured) into high-performance PFPE elastomers in one step. To investigate how fundamental changes in the PFPE molecular structure correlate to bulk and surface properties, the variable functional end group, molecular weight, and the copolymer content were systematically explored in relation to thermal stability, contact angle/surface tension, modulus, and biofouling behavior. The morphologies of these PFPE materials were studied using differential scanning calorimetry, dynamic mechanical thermal analysis, and small-angle X-ray scattering. From these studies, it was determined that clusters of polymerized functional end groups were found to be nanophase separated within the PFPE matrix. By varying the cross-link density, the Young’s modulus of the fully cross-linked PFPE elastomeric film could be tuned from 1.5 to 90 MPa with a critical surface tension of 8.6−16 mN/m. The marine antifouling and fouling-release properties of the cross-linked PFPE elastomeric coatings were evaluated by settlement and release assays involving zoospores and sporelings (young plants), respectively, of green fouling alga Ulva.

Crosslinked perfluoropolyether solid electrolytes for lithium ion transport

“…25, exhibit signatures of a glass transition, and the T g s of the samples are indicated by arrows on the DSC curves. The glass transition temperature associated with the motion of the fluorine atoms in pure PFPE liquids occurs at − 90°C, a value that is outside the range of the instrument that we have access to [45]. The glass transition seen between − 40 and − 60°C obtained from liquid PFPE_0.10 may reflect the motion of the urethane methacrylate end-groups.…”

Surface properties and surface patterning of UV-curable coating using perfluorosilane-treated nanosilica

“…where  is the static contact angle, L is the surface tension of a probe liquid, and d S and p S are the dispersive component and the polar component of the liquid surface tension, respectively [14]. In this study, water and diiodomethane were used as the polar and nonpolar probe liquids; their surface tensions are shown in Table 2.…”

“…In the past decade, UV-curable coatings as non-solvent agents have become fast growth technology [6][7][8][9][10][11] and hydrophobic UV-curable coatings are a subject of focus for many scientists [12][13][14][15].…”

“…Patterned hydrophobic UV-curable coatings can be used in hydrophobicity [12][13][14]28], self-cleaning effects [29], to control adhesion, and capture water from fog [30]. Filler-polymer interactions can be enhanced by grafting organic molecular coupling agents onto a filler surface [31].…”

Prevention of protein and polymeric nanoparticles adsorption using perfluoropolyether

“…The fluoroalkyl chain in block copolymers lowers the surface energy, and freely moving PEG chains are exploited to reduce biofouling through conformational change [13,14]. Modified and microstructure-controlled fluoropolymers were further applied to reduce surface energy while enhancing static water contact angles [15][16][17]. Fluoroalkyl groups were applied to inorganic materials to endow antifouling properties [18].…”