Dual-Polyelectrolyte Adsorption of Poly(allylamine Hydrochloride) and Xylan Onto Recycled Unbleached Kraft Pulps

Abstract

The effects of a double polyelectrolyte adsorption of poly(allylamine hydrochloride) (PAH) and xylan (Xyl) on a recycled unbleached softwood kraft pulp were studied. The kinetics of PAH adsorption on this pulp was analyzed by building adsorption isotherms and by estimating the surface nitrogen adsorbed through the X-ray photoelectron spectroscopy (XPS) technique. It was found that at pH 7.5, 0.01N NaCl, and short adsorption time, PAH is mainly adsorbed on the fiber surface. Adsorption isotherms of xylan on untreated and on previously PAH-treated pulps at different ionic strengths were built, and the effects of the amount of PAH on xylan adsorption were considered. It was found that when ionic strength was lower than 0.01N NaCl, a PAH pretreatment was necessary to achieve high levels of xylan adsorption at room temperature and short adsorption times. Nevertheless, when ionic strength was 0.1N NaCl, 0.3% xylan on pulp could be directly adsorbed on untreated pulp. Finally, it is shown that the dual-polyelectrolyte adsorption on this pulp is a feasible technique for improving paper tensile strength.

Prospects for Maintaining Strength of Paper and Paperboard Products While Using Less Forest Resources: A Review

“…a dual system, has been shown to be highly effective for increasing dry strength (Linke 1968;Wielema and Brouwer 2003;Esser et al 2005;Galván et al 2012). As shown by , it can be an effective strategy to add just enough of the cationic additive, in the first step, so that the fiber surfaces are saturated; subsequent addition of the anionic component of the dry-strength system was found to be especially effective.…”

Complexes of xylan and synthetic polyelectrolytes. Characterization and adsorption onto high quality unbleached fibres

“…The anionic polyelectrolyte used was 4-O-methylglucuronoxylan, isolated from beechwood by alkaline extraction (Sigma-Aldrich product number X-4252) with an average molecular mass of Mw: 18.7 kDa, and polydispersity of 1.8 determined by size exclusion cromatography (SEC). As previously published (Galván et al, 2012;Linder, Bergman, Bodin, & Gatenholm, 2003), fresh xylan solutions (1 meq/L) were daily prepared by adding the commercial solid xylan to NaOH 10 −4 N solution and heating it in a water bath at 95 • C for 15 min to dissolve xylan. As described by Salyers, Gherardini, and O'Brien (1981), xylan solution concentration was determined using the phenol-sulphuric acid spectrophotometric method (Hodge & Hofreiter, 1962).…”

“…Particularly, in the paper industry several studies have been focused on achieving remarkable improvements in paper strength properties by pre-forming polyelectrolyte complexes and letting them interact with fibres (Eriksson, Torgnysdotter, & Wågberg, 2006;Fatehi, Kititerakun, Ni, & Xiao, 2010;Gärdlund, Forsström, Andreasson, & Wågberg, 2005;Lofton, Moore, Hubbe, & Lee, 2005). This alternative, compared with the well known dual system (Galván, Mocchiutti, Cornaglia, & Zanuttini, 2012; or multilayer system (Eriksson et al, 2006;Wågberg, Forsberg, Johansson, & Juntti, 2002), has the advantages of being simpler to apply, and requiring lower investment for the industry (Ankerfors, 2008).…”

Adsorption of Xylan onto Cellulose Fibers Pretreated with Cationic Polyelectrolyte and Its Effect on Paper Properties

“…The charge density of cationic xylan influences both the amount of adsorption and the structure of cationic xylan layers adsorbed on the model cellulose film (Galván et al 2012;Lee et al 2014). This suggests that electrostatic attraction plays an important role in xylan adsorption onto cellulose fiber.…”