Role of substrate outgassing on the formation dynamics of either hydrophilic or hydrophobic wood surfaces in atmospheric-pressure, organosilicon plasmas

SURFACE & COATINGS TECHNOLOGY

卷:234

Article

Levasseur, O.¹  Stafford, L.¹  Gherardi, N.^2,3,4,5,6  Naude, N.^2,3,4,5,6  Beche, E.⁷  Esvan, J.⁸  Blanchet, P.⁹  Riedl, B.¹⁰  Sarkissian, A.¹¹ 

[1] Univ Montreal, Dept Phys, Montreal, PQ H3C 3J7, Canada

[2] Univ Toulouse, F-31062 Toulouse 9, France

[3] UPS, F-31062 Toulouse 9, France

[4] INPT, F-31062 Toulouse 9, France

[5] LAPLACE, F-31062 Toulouse 9, France

[6] CNRS, F-31062 Toulouse 9, France

[7] Ctr Four Solaire Felix TROMBE, PROMES CNRS UPR 8521, F-66120 Odeillo Font Romeu, Font Romeu, France

[8] CIRIMAT ENSIACET, F-31030 Toulouse 4, France

[9] FPInnovat Div Prod Bois, Quebec City, PQ G1P 4R4, Canada

[10] Univ Laval, Ctr Rech Bois, Quebec City, PQ G1K 7P4, Canada

[11] Plasmionique, Varennes, PQ J3X 1S2, Canada

关键词: Atmospheric-pressure plasmas;    Dielectric barrier discharges;    Functional coatings;    Organosilicon plasmas;    Wood;   

DOI  :  10.1016/j.surfcoat.2013.05.045

来源: Elsevier

【 摘 要 】

This work examines the influence of substrate outgassing on the deposition dynamics of either hydrophilic or hydrophobic coatings on wood surfaces in organosilicon, dielectric barrier discharges. Sugar maple and black spruce wood samples were placed on the bottom electrode and the discharge was sustained in N-2-HMDSO (hexamethyldisiloxane) gas mixtures by applying a 24 kV peak-to-peak voltage at 2 kHz. Current-voltage characteristics revealed a transition from a filamentary to a homogeneous discharge with increasing plasma treatment time, t. Based on optical emission spectroscopy, the filamentary behavior was ascribed to the release of air and humidity from the wood substrate following discharge exposure which produced significant quenching of N-2 metastables. This effect vanished at longer treatment times due to the nearly complete pumping of products from the wood substrate and the progressive deposition of a barrier layer. Analysis of the surface wettability through static, water contact angles (WCAs) and of the surface composition through Fourier-Transform-Infra-Red-Spectroscopy and X-ray-Photoelectron-Spectroscopy indicated that for t < 10 min, the wood surface was more hydrophilic due to the formation of a SiOx layer, a typical behavior for HMDSO deposition in presence of oxygen. On the other hand, for t > 10 min, the static WCA increased up to similar to 140 degrees due to the deposition of hydrophobic Si(CH3)(3)-O-Si(CH3)(2), Si(CH3)(3), and Si(CH3)(2) functional groups. (C) 2013 Elsevier B.V. All rights reserved.

【 授权许可】

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