Interpolymer from starch xanthate and polyamide–polyamine–epichlorohydrin resin: Structure and papermaking application

Abstract

synopsisThe efficacy of oxidatively crosslinked starch xanthate for improving web and drystrength properties of paper prompted the present study of an alternative, interpolymeric crosslinking procedure. Sodium starch xanthate of degrees of substitution 0.05-0.25 was reacted with a commercial paper additive (a polyamide-polyamine-epichlorohydrin wet-strength resin) which was found to contain 3-hydroxyazetidinium chloride, epoxypropyl, and chlorohydrin groups (3: 1: 1) to give an interpolymer crosslinked by both ionic and covalent bonds. Model systems, in conjunction with nuclear magnetic resonance, infrared, and ultraviolet spectral data, served to elucidate reaction mechanisms and structures of the interpolymer and the commercial resin. Reaction conditions that favored formation of either ionic (polysalt) or covalent (xanthate ester) crosslinks were investigated. In preliminary evaluations, incorporation of the interpolymer into paper handsheets resulted in excellent wet-and dry-strength improvements.

1H‐ and 13C‐NMR analyses of aqueous polyamideamine–epichlorohydrin resin solutions

“…Thus, AZR content slightly decreases from the initial value with an increase in the heating time by consuming the AZR group for crosslinking reactions between polyamideamine chains. The AZR content of PAE-II prepared in this study is a little higher than those (60 -70%) reported by Carr et al 1 and Bates. 4 The value reported by Carr et al 1 was obtained from 1 H-NMR spectra of once-precipitated PAE samples.…”

“…All chemical shifts of PAE carbons obtained in this study were almost equal to those reported by Kricheldorf. 3 On the other hand, assignment of some proton signals of PAE in Figure 3 are clearly different from those for PAE/ DMSO solutions reported by Carr et al 1 and Devore et al 2 Their results may be wrong, or chemical shifts of PAE protons in DMSO are remarkably different from those in water.…”

“…Carr et al 1 and Devore et al 2 reported signal assignment of 1 H-NMR spectra of PAE. The method the authors used to isolate the PAE for NMR analysis was precipitation by pouring its aqueous solution into acetone and re-dissolving the dried precipitate in dimethylsulfoxide-d 6 (DMSO-d 6 ).…”

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

“…Several studies have employed the principles of polyelectrolyte complexation as a means of treating cellulosic fiber surfaces with relatively high amounts of hydrophilic polyelectrolyte material, thus enhancing paper's dry strength (Carr et al 1974(Carr et al , 1977Heath et al 1974;Nagata 1991;Gärdlund et al 2003Gärdlund et al , 2005Gernandt et al 2003;Koljonen et al 2003;Hubbe 2005a;Lofton et al 2005;Maximova et al 2005;Heermann et al 2006;Lvov et al 2006;Torgnysdøtter and Wågberg 2006;Truppner et al 2006;Vainio et al 2006;Larsson and Wågberg 2008;Ankerfors et al 2009Ankerfors et al , 2012Fatehhi et al 2009;Sang et al 2010). As noted by Rojas and Neuman (1999), even in papermaking systems where there has been no explicit intention to form polyelectrolyte complexes (PECs), such effects still can play a role due to interaction between a cationic polyelectrolyte and various anionic polyelectrolytes already present in the suspension, such as dissolved hemicellulose species.…”

Changes in the composition of wastewater as a result of dehydrochlorination of 1,3-dichloropropan-2-ol under different process conditions

“…The largest world producers of epichlorohydrin, according to generation capacity, include: Dow Chemical (31% of global capacity), Hexion Specialty Chemicals (12%), Solvay (6%) and Nan Ya (6%) (year 2010) 10 . The demand for epichlorohydrin in the world market is still increasing.…”