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Liquid-assisted plasma-enhanced chemical vapor deposition (LA-PECVD) provides a convenient approach toward the preparation of functional surfaces. In this work, the LA-PECVD approach is reported for the high deposition rate of tuneable catechol and quinone-functionalized coatings from plasma polymerization of vinyltrimethoxysilane (VTMOS) and dopamine acrylamide (DOA). Most particularly, the influence of the liquid precursor delivery rate and of the plasma power density on the chemistry and morphology of the formed layers are investigated. Precursor delivery rate and plasma power conditions are found, through mass measurement, XPS, FTIR, and Raman spectroscopy, to enable the high deposition rate of cross-linked coatings. Interestingly, the integration and conservation of the catechol functional group from the DOA monomer are highlighted through the reduction of a silver nitrate solution and silver nanoparticles formation observation via SEM/EDX. Due to the presence of oxidant species and to the bombardment of the layer with highly energetic species, quinone groups formation is likely to occur during the plasma treatment and is then highlighted via ToF-SIMS analyses of a surface successfully derivatized with a β-lactamase. The conservation of both functional groups on the surface makes this type of layer promising for numerous applications. Quinone groups provide a real platform for the immobilization of biomolecules with various properties, e.g., antibiotics degradation, antibacterial, while the catechol groups are interesting for trapping radicals or metal ions for water treatment applications.

In this work, an atmospheric-pressure dielectric barrier discharge process is exploited for the fast deposition of adherent epoxy-rich layers acting as a versatile platform for the efficient one-step biomolecule immobilization in mild aqueous conditions. Particular attention is given to the influence of the plasma process parameters on the chemical and morphological properties of the deposited layers and on their subsequent exploitation for chemical interfacial reactions. As a proof-of-concept, two enzymes with drastically different biological properties, namely dispersin B and a laccase, are immobilized onto functionalized metallic surfaces. The pH of the enzyme solution appears as a key parameter to control the amount of immobilized enzyme on the plasma functionalized surfaces, thus leading to bioactive surfaces with improved stability and activity.

Herein, plasma deposited thermally responsive thin polymer films from N-vinylcaprolactam (NVCL) is reported for the first time by using a low pressure RF plasma process. While FT-IR and XPS analyses highlight the film chemistry, ToF-SIMS combined with MALDI-MS analyses allow to accurately identify different oligomer distributions in the deposited film. The switching behavior of these smart surfaces is confirmed with water contact angle measurements at low and high temperatures, allowing also to estimate the Lower Critical Solution Temperature.

The objective of this work is to investigate a novel top–down synthesis route toward the elaboration of nanopatterned polymer surfaces by combining thin polymer structuring (polymer-demixing) and plasma etching techniques. Thanks to this original approach, the adjustment of the parameters during the wet chemical and plasma steps allows independent tuning of the lateral dimension of the polymer structures (diameter) and the height of the pillars. The nanopatterning description of two different polymers, namely polyethylene naphthalate and polyimide, is reported. Johnson–Kendall–Roberts (JKR) adhesion tests are carried out to compare the adhesive property of the patterned and non-patterned polymer surfaces. These measurements allow highlighting the importance of the polymer viscoelasticity for future development of bio-inspired polymer-based dry adhesives.

A natural vulcanized rubber was treated by atmospheric dielectric barrier discharges to improve its adhesion to silicone adhesive. The different operating conditions were: (i) the nature of the plasma gas associated or not with organic precursors such as acetic acid or allyl alcohol, (ii) the concentration of the precursors in the gas phase, (iii) the power discharge (between 500 and 1 000 W) and (iv) the treatment time (between 18 and 30 s). The surface modifications induced by the plasma treatments were characterized by water contact angle measurements and XPS analyses. T-peel tests were carried out to evaluate the influence of the surface modifications on the adhesion properties of the treated rubber. The efficiency of plasma treatments with the use of allyl alcohol has been proved for the adhesion improvement of natural vulcanized rubbers to a silicone adhesive (increase by a factor of 10). XPS analysis revealed that this treatment induced an increase of the total oxygen amount in the sample with the preferential formation of CO bonds, which might explain the adhesion improvement observed.

Adhesion of epoxy resins on copper foils for printed circuit board (PCB) applications is improved by nearly a factor of 5, using surface cleaning and deposition of a 15-nm-thick film in a low-pressure remote plasma-enhanced chemical vapor deposition process. The cleaning pretreatment, using an N2–O2 oxidizing gas mixture with moderate heating (343 K), gives the best results. This pretreatment removes the carbonaceous contaminants present on the topmost surface of the sample and slightly oxidizes the copper into CuO. This oxide is then reduced during the deposition treatment, presumably by reaction with the aminopropyltrimethoxysilane (APTMS) precursor. The surface roughness is unchanged after treatment, thereby showing that the improvement of the copper/epoxy adhesion is only due to the chemistry of the plasma coating. Applying these results to dielectric barrier discharges allows us to achieve the same level of adhesion, which, therefore, does not depend on the process.