Deposition of fluorocarbon groups on wood surfaces using the jet of an atmospheric-pressure dielectric barrier discharge

作者:Levasseur O; Vlad M; Profili J; Gherardi N; Sarkissian A; Stafford L*
来源:Wood Science and Technology, 2017, 51(6): 1339-1352.
DOI:10.1007/s00226-017-0958-x

摘要

This work reports the functionalization of sugar maple (Acer saccharum) wood surfaces following their exposure to the jet of an atmospheric-pressure dielectric barrier discharge operated in either Ar or N-2 with C3F8 (octafluoropropane) as the growth precursor for plasma-enhanced chemical vapour deposition. Analysis of the current-voltage characteristics (I-V) revealed a filamentary behaviour in all conditions. While more intense current peaks were observed after addition of C3F8 in Ar, a decrease in the discharge current was seen in N-2/C3F8 plasmas. Optical emission spectroscopy showed the apparition of a CF2 (+) continuum and CF2 rovibrational bands between 225 and 350 nm with increasing applied voltage and precursor concentration in the Ar plasmas; a feature ascribed to the presence of plasma-generated C3F8 fragments. In such conditions, water contact angle (WCA) measurements indicated that freshly sanded wood samples became highly hydrophobic, with WCAs in the 140A degrees range and excellent dimensional stability for a period of up to 125 days. X-ray photoelectron spectroscopy revealed that such behaviours result from the deposition of highly hydrophobic CF (x) groups on the surface. On the other hand, no increase in surface hydrophobicity was observed following exposure to the jet of N-2/C3F8 plasmas, probably due to their much lower precursor fragmentation levels.

  • 出版日期2017-11