title: Hydrophobic properties conferred to Kraft pulp by a laccase-catalysed treatment with lauryl gallate.
abstract: Hydrophobic properties were conferred to a high-lignin-content Kraft pulp by a laccase-catalysed treatment in the presence of lauryl gallate (LG). The treatment resulted in a two-fold increase in contact angle and conferred water absorption resistance to the pulp. Kappa number was increased, indicating that some phenolic compounds were incorporated in the pulp. A control treatment with LG alone did not affect water absorption, demonstrating that laccase was essential to attain these new properties. The loss of hydrophobicity after an acetone Soxhlet extraction highlighted that adsorbed acetone-soluble compounds played a key role in the properties. GC-FID and HPSEC-UV analysis of the acetone extract indicated the formation of dodecanol and different phenolic oligomers. SEM images showed the treatment-induced changes in the fibre network. Additional experiments with various reaction times and reactant concentrations highlighted the role of LG oxidation products in the introduction of absorption resistance.
authors.affiliation: New Materials Division, FCBA, Intechfibres, Domaine Universitaire, BP 251, F-38044 Grenoble Cedex 9, France. celine.reynaud@fcba.fr
authors.forename: Céline
authors.initials: C
authors.lastname: Reynaud
authors.forename: Sandra
authors.initials: S
authors.lastname: Tapin-Lingua
authors.forename: Graziano
authors.initials: G
authors.lastname: Elegir
authors.forename: Michel
authors.initials: M
authors.lastname: Petit-Conil
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Baumberger
mesh_terms: D000096:Acetone / Q000737:chemistry; D000327:Adsorption; D005707:Gallic Acid / Q000031:analogs & derivatives* / Q000737:chemistry; D055772:Green Chemistry Technology / Q000379:methods; D057927:Hydrophobic and Hydrophilic Interactions; D042845:Laccase / Q000378:metabolism*; D010209:Paper; D014934:Wood / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000096:Acetone; C008259:lauryl gallate; D005707:Gallic Acid; D042845:Laccase
keywords: Adsorption; Hydrophobicity; Laccase; Lauryl gallate; Papermaking