Ultrahigh molecular weight, lignosulfonate-based polymers: preparation, self-assembly behaviours and dispersion property in coal–water slurry

Abstract

Using a novel and facile method, we synthesized a family of ultrahigh molecular weight, lignosulfonatebased polymers (ALSs) via alkyl chain coupling polymerization. Gel permeation chromatography (GPC) showed a significant increase in weight-average molecular weights (Mws), from 42 800 Da of ALS1 to 251 000 Da of ALS5-one of the highest Mws among reported lignosulfonates (LSs) to date. Functional group content measurements, FTIR and 1 H-NMR confirmed the efficient polymerization by nucleophilic substitution coupling mechanism and suggested a straightforward relationship between the polymerization of lignosulfonate (LS) and consumption of phenolic hydroxyl groups. Moreover, hollow nanospheres were obtained via self-assembly of water-soluble ALS and were investigated by DLS, SEM, TEM and AFM. The hollow sphere structure, with a hydrophilic core and a hydrophobic shell, was confirmed by XPS and elemental analysis. Stable, quasi-solid nanospheres were obtained from ALS by the addition of cetyl trimethyl ammonium bromide (CTAB). Furthermore, ALS2, with its relatively high molecular weight, showed unexpectedly better dispersion properties than the raw material LS and naphthalene sulfonate formaldehyde condensate (NSF) for coal-water slurry. The effective polymerization route to improving Mw and the self-assembly from polymer-only ALS provide novel avenues for high-value application of lignin, a sustainable and abundant bioresource.

Effect of aggregation behavior and phenolic hydroxyl group content on the performance of lignosulfonate doped PEDOT as a hole extraction layer in polymer solar cells

“…Secondly, the high acidity of PEDOT:PSS is from the anionic dispersant PSS, however, the limited sulfonation degree of LS and ALS will provide high pH for the dispersed conductive polymer, which will reduce its corrosion of ITO. Thirdly, as a water soluble polymer from biomass, lignosulfonate showed good dispersion properties in various industrial fields such as dimethomorph water-dispersible granule, 41 cement-water systems, 42 TiO 2 suspension 43 and coal water slurry in our group 14 .…”

“…To the most of our knowledge, similar self-assembly from water soluble amorphous polymer has been rarely reported, to date. In our previous work, 14,15 It is well known amorphous lignosulfonate (LS) exist as small aggregate with nano-size in solution. However the unique block-like aggregate from LS in selective solvent is rarely reported and very different with nanospheres of LS.…”

“…[29][30][31][32][33][34][35][36] Recently, we reported that PEDOT:SL as hole transporting material exhibited promising performance in polymer solar cells. 37 In order to study the effect of -OH and aggregation behaviour of lignosulfonate for the performance of PSCs, we choose LS and ALSs as starting materials in our previous manuscript 14 to study the effect in detail. The motivation for this is also in based on the following considerations.…”

Metal Ion‐Catalyzed Hydrothermal Liquefaction of Calcium Lignosulfonate in Subcritical Water

“…S1 in the Supporting Information, typical absorptions of lignin structure were clearly recognized, including O-H stretching vibration (peak 1), C-H stretching vibration in methyl and methylene groups (peaks 2 and 3), aromatic skeletal vibrations (peaks 4, 5, and 7), and aromatic ring breathing (peak 8) [29]. In addition, peak 9 (1042 cm -1 ) and peak 10 (652 cm -1 ) were assigned to the absorptions of S-O bonds [30,31], which benefited from the sulfonic groups.…”

A highly efficient dispersant from black liquor for carbendazim suspension concentrate: Preparation, self‐assembly behavior and investigation of dispersion mechanism

“…However, biopolymers, including proteins, nucleic acids, viruses, lipid, glucose, chitosan, lignin, cellulose, and hemicellulose, and so on, have attracted great attention for their biocompatibility and biodegradability. Biopolymers have emerged as an ideal candidate in the formation of nano‐/micro‐ materials via self‐assembly because of their safety, environment impact and low cost . Lignin, a natural biopolymer, has stimulated great fundamental interest and has widespread applications in many fields because of its advantages such as low environmental impact, abundant in source and lower cost .…”