Modification of hardwood samples in the flowing afterglow of N-2-O-2 dielectric barrier discharges open to ambient air

作者：Pregent J; Vand**urger L; Blanchard V; Blanchet P; Riedl B; Sarkissian A; Stafford L^*

来源：Cellulose, 2015, 22(5): 3397-3408.

DOI：10.1007/s10570-015-0736-6

• Wood
• Hardwood
• Plasma modification
• Wettability

The effect of O-2 addition in the gas feed of an open-to-air N-2-O-2 dielectric barrier discharge (DBD) on the surface modification of sugar maple hardwood samples is reported. After treatment by N-2-O-2 plasma, an increase of the contact angle with water and a decrease of the contact angle with diiodomethane was observed. X-ray photoelectron spectroscopy and Fourier-transform infra-red analyses further reveal a decrease of the O/C as well as increase of the C=O peak and surface aromaticity. When O-2 is added to the nominally pure N-2 DBD, the discharge transits from a homogeneous regime to a filamentary regime with increased dissipated power and neutral gas temperature. As a result, surface modification by N-2-O-2 plasmas becomes similar to those occurring under a low-temperature heat treatment of wood surfaces. In such conditions, a mechanism involving the thermally-activated deacetylation and depolymerisation of hemicelluloses and cross-linking between lignin and furfural and hydroxylmethylfurfural, leading to the increase of wood hydrophobicity is proposed.

• 出版日期2015-10