Back to Search Start Over

Modification of Paper Surface by All-Lignin Coating Formulations

Authors :
Patricia I. F. Pinto
Sandra Magina
Sara Fateixa
Paula C. R. Pinto
Falk Liebner
Dmitry V. Evtuguin
Source :
Materials, Vol 15, Iss 22, p 7869 (2022)
Publication Year :
2022
Publisher :
MDPI AG, 2022.

Abstract

All-lignin coating formulations were prepared while combining water-soluble cationic kraft lignin (quaternized LignoBoost®, CL) and anionic lignosulphonate (LS). The electrostatic attraction between positively charged CL and negatively charged LS led to the formation of insoluble self-organized macromolecule aggregates that align to films. The structures of the formed layers were evaluated by atomic force microscopy (AFM), firstly on glass lamina using dip-coating deposition and then on handsheets and industrial uncoated paper using roll-to-roll coating in a layer-by-layer mode. Coated samples were also characterized by optical microscopy, scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (SEM/EDS), and contact angle measurements. It was suggested that the structure of all-lignin aggregates is the result of the interaction of amphiphilic water-soluble lignin molecules leading to their specifically ordered mutual arrangement depending on the order and the mode of their application on the surface. The all-lignin coating of cellulosic fiber imparts lower air permeability and lower free surface energy to paper, mainly due to a decrease in surface polarity, thus promoting the paper’s hydrophobic properties. Moderate loading of lignin coating formulations (5–6 g m−2) did not affect the mechanical strength of the paper.

Details

Language :
English
ISSN :
19961944
Volume :
15
Issue :
22
Database :
Directory of Open Access Journals
Journal :
Materials
Publication Type :
Academic Journal
Accession number :
edsdoj.39b368c3beb456cae95383ea7e362cc
Document Type :
article
Full Text :
https://doi.org/10.3390/ma15227869