Cellulose nanofibrils—adsorption with poly(amideamine) epichlorohydrin studied by QCM-D and application as a paper strength additive

Abstract

In this paper cellulose nanofibrils were used together with a cationic polylelectrolyte, poly(amideamine) epichlorohydrin (PAE), to enhance the wet and the dry strength of paper. The adsorption of nanofibrils and PAE on cellulose model surfaces was studied using quartz crystal microbalance with dissipation (QCM-D) and atomic force microscopy (AFM). The differences in fibril and polyelectrolyte adding strategies onto cellulose fibres were studied by comparing layer-structures and nano-aggregates formed by the nanofibrils and PAE. The results showed that when PAE was first adsorbed on the model fibre surface a uniform and viscous layer of nanofibrils could be adsorbed. When PAE and nanofibrils were adsorbed as cationic aggregates a non-uniform and more rigid layer was adsorbed. Paper sheets were prepared using both the bi-layer and nano-aggregate adding strategy of the nanofibrils and PAE. When PAE and nanofibrils were adsorbed on pulp fibres as a bi-layer system significant increase in both wet and dry tensile strength of paper could be achieved even at low added amounts of PAE. When the substances were added as nano-aggregates the improvements in paper strength properties were not as significant. Bulk and surface nitrogen content analyses of the paper samples showed that the adding strategy does not affect the total adsorbed amount of PAE but it has a strong effect on distribution of substances in the paper matrix which has a crucial effect on paper wet and dry strength development.

Surface properties of distinct nanofibrillated celluloses assessed by inverse gas chromatography

“…Amongst its more relevant properties are the relatively high specific surface area in comparison to that of the pristine cellulose fibres (values can be higher than 100 m 2 /g), the viscosity (rheology) properties of the viscous NFC gel, the high tensile strength and the high light transmittance of the corresponding NFC films. NFC has thus been used in formulations as a viscosity modifier, as gel for biomedical applications, as a mechanical reinforcement material in (nano)composites, including (nano)paper, for paper coating, in films for food packaging and for electronic devices [2][3][4][5][6][7][8]. Its barrier properties namely for the water vapour and molecular oxygen have been highlighted [1].…”

Surface treatment of cellulose nanocrystals (CNC): effects on dispersion rheology

“…That azetidinium salts react with carboxylic acids has been shown by Börjesson and Westman (2016) who esterified oxidized hemicelluloses with azetidinium salts in DMSO at 90°C. It has been reported by several groups that ionic complexes, non-covalent complexes, are formed with tetraalkyl ammonium salts with CNC (Dong and Gray 1997;Ahola et al 2008;Aloulou et al 2004;Cranston and Gray 2006). All of these studies where performed at 60°C or lower reaction temperatures.…”

Enzymatic Refining and Cellulose Nanofiber Addition in Papermaking Processes from Recycled and Deinked Slurries

“…The suitability of CNFs as a paper additive has been studied by several authors in recent years (Ahola et al 2008;Eriksen et al 2008;Sehaqui et al 2011;González et al 2012). The level of CNF addition ranged between 0 and 3 wt% to avoid excessive loss of the drainability of the pulp suspension.…”

“…One of the promising options is the addition of cellulose nanofibers (CNFs) as a strength-reinforcing additive to improve the physical and mechanical properties of paper (Ahola et al 2008;Taipale et al 2010;González et al 2012;Delgado-Aguilar et al 2014). However, in most of the cases, a decrease in the drainage rate was also noted because of the ability of CNF to hold huge amounts of water (González et al 2012, Delgado-Aguilar et al 2015a.…”