Coating of laccase-activated phenols for the industrially-feasible functionalization of cellulose-based substrates

Abstract

The present work describes an innovative method for the hydrophobization of cellulosic material by impregnation with an enzymatically obtained functionalization solution (FS). Application of FS to the surface of previously formed cellulose sheets was found to confer them hydrophobic properties. The absorbance of functionalized sheets was assessed with the water-drop test (WDT), and their hydrophobicity from their contact angle (WCA) and the surface free energy (SFE) as determined with a goniophotometer. The proposed method is an effective choice for the hydrophobization of paper sheets, with absorption times of up to 4000 s and WCA values around 130°. Treating eucalyptus paper sheets dramatically decreased SFE (from 55 to 10 mJ/m2), and evidences on the grafting of the FS onto the cellulosic sheets were assessed by using ATR-FTIR. The stability of FS and the control solutions was characterized in terms of Z potential and light scattering measurements