T. J. Wood

Electroless deposition of multi-functional zinc oxide surfaces displaying photoconductive, superhydrophobic, photowetting, and antibacterial properties

Electroless growth of zinc oxide has been accomplished using palladium catalysts coordinated to pulsed plasma deposited poly(4-vinylpyridine) nanolayers. Four different and concurrent functional properties have been identified, which encompass photoconductivity, superhydrophobicity, photo-switchable wetting, and bacterial killing.

Impact of Picoliter Droplets on Superhydrophobic Surfaces with Ultralow Spreading Ratios

The impact of picoliter-sized water droplets on superhydrophobic CF(4) plasma fluorinated polybutadiene surfaces is investigated with high-speed imaging. Variation of the surface topography by plasmachemical modification enables the dynamics of wetting to be precisely controlled. Final spreading ratios as low as 0.63 can be achieved. A comparison of the maximum spreading ratio and droplet oscillation frequencies to models described in the literature shows that both are found to be much lower than theoretically predicted.

Super-Adhesive Polymer–Silica Nanocomposite Layers

Atomized spray plasma deposition (ASPD) using a precursor mixture of 2-hydroxyethyl methacrylate and methacryloyl-functionalized 15 nm silica nanoparticles leads to the formation of poly(2-hydroxyethyl methacrylate)-silica nanocomposite layers. The direct application of these coatings to overlapping glass-glass joints gives rise to excellent in situ adhesion reaching 84 MPa shear bond strength and 6 GPa shear modulus prior to the onset of adherent (bulk glass) failure. This significant enhancement in interfacial adhesion arises due to the silica nanoparticle surface methacryloyl groups enhancing cross-linking throughout the nanocomposite layer.

Pulsed Plasmachemical Deposition of Highly Proton Conducting Composite Sulfonic Acid–Carboxylic Acid Films

Graft polymerization of sulfonic acid monomers onto structurally well-defined pulsed plasma poly(maleic anhydride) layers yields a composite carboxylic acid-sulfonic acid network. These bifunctional films are shown to exhibit high proton conductivity (125 mS cm(-1)) as well as good stability in water.

A Substrate-Independent Lift-Off Approach for Patterning Functional Surfaces

A lift-off method for creating multifunctional patterned surfaces has been devised. It entails consecutive pulsed plasmachemical deposition of a reactive bottom layer and a protective top release layer. By way of example, a bottom/top layer combination comprising pulsed plasma deposited poly(glycidyl methacrylate)/poly(pentafluorostyrene) has been shown to display selective adhesive lift-off of the latter. Application of a prepatterned adhesive template yields well-defined arrays of reactive epoxide functionality surrounded by a passive fluoropolymer background or vice versa.

Oxidative atomized spray deposition of electrically conductive poly(3,4-ethylenedioxythiophene)

Atomized spray deposition of 3,4-ethylenedioxythiophene monomer in the presence of triflic anhydride vapour yields electrically conducting poly(3,4-ethylenedioxythiophene) layers.

Highly ion-conducting poly(ionic liquid) layers.

Highly ion-conducting poly(ionic liquid) thin films have been prepared in the absence of solvents utilizing a simple 2-step approach comprising pulsed plasmachemical deposition of 1-allylimidazole followed by vapour-phase quaternization with 1-bromobutane.

Ion- and electron-conducting platinum-polymer nanocomposite thin films.

Non-equilibrium plasmachemical deposition using platinum(II) hexafluoroacetylacetonate precursor leads to the single-step formation of nanocomposite layers comprising an organic host matrix embedded with metal particles of size less than 5 nm. These multifunctional nanocomposite films are found to display both ionic and electronic conductivities.

Atomized Spray Plasma Deposition of Structurally Well-Defined Bioactive Coatings

Structurally well-defined bioactive films have been prepared in a single solventless step by atomizing precursor molecules into a non-equilibrium electrical discharge. By way of example, atomized spray plasma deposition is used to form poly(alkyl acrylate) arrays for phospholipid immobilization, and poly(N-acryloylsarcosine methyl ester) protein-resistant surfaces.Graphical Abstract

Combining plasmachemical emulsion-templating with ATRP to create macroporous lipophilic surfaces

Well-defined alkyl chain side group polymer brushes have been tethered onto high surface area macroporous pulsed plasmachemical emulsion-templated poly(vinylbenzyl chloride) initiator layers (typically 600-700 m2 g(-1)) using atom transfer radical polymerisation (ATRP). Immobilisation of phospholipids onto these bioactive surfaces is found to occur through interdigitation, and the efficacy of lipid binding is governed by the alkyl side group chain length of the polymer brushes.