Deposition of functional coatings from acrylic acid and octamethylcyclotetrasiloxane onto steel using an atmospheric pressure dielectric barrier discharge

• Published in: Surface & coatings technology Vol. 203; no. 5; pp. 822 - 825
• Main Authors: Beck, A.J., Short, R.D., Matthews, A.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 25.12.2008; Elsevier
• Subjects: Acid; APGD; Applied sciences; Cross-disciplinary physics: materials science; rheology; DBD; Exact sciences and technology; Materials science; Metals. Metallurgy; Physics; Plasma; Production techniques; Siloxane; Surface treatment; Surface treatments; XPS; Plasma; APGD; Acid; XPS; Siloxane; DBD; Atmospheric pressure; Dielectric materials; Acrylic acid; Surface treatments; Coatings; Photoelectron spectroscopy
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2008.05.017

A parallel plate dielectric barrier glow discharge operating at around atmospheric pressure was used to deposit functional coatings onto thin (< 3 mm) sheets of steel. An organic precursor was introduced with helium into a mixing chamber connected to the plasma region. X-ray photoelectron spectroscopy showed that at high precursor flow rate and low power, the monomer was only slightly fragmented during the plasma process. Coatings containing a range of concentrations (12.6 to 29.7%) of carboxylate were prepared from acrylic acid. The surfaces with higher concentrations of carboxylates had low (< 20°) contact angles with water. Coatings with a range of concentrations of carbon, silicon and oxygen were prepared from octamethylcyclotetrasiloxane. Extremely hydrophobic coatings (contact angles > 130°) were produced using lower power and higher flow rate of octamethylcyclotetrasiloxane whereas relatively more hydrophilic coatings (contact angles 50 to 100°) resulted when a lower flow rate of octamethylcyclotetrasiloxane was used.