1,4-butanesultone Sulfonated Lignin And Its Dispersion Properties

Industrial lignin was from pulp and paper making industry, including alkali lignin(AL) from black liquor, which accounted for more than 90%, and lignosulfonate(LS). Poor water solubility and low reactivity, severely limit the industrial applications of industrial lignin.With the increasing concern on the fossil energy and environment pollution problems, a variety of chemical modification approaches including sulfonation, amination, oxidation, and alkylation graft copolymerization have been investigated to overcome the obstacles in order to make full use of industrial lignin. Sulfonation modification was one of the most efficient ways to improve the properties of lignin, which had been studied extensively and reported.The sulfonation process which have reported, the reaction sites mainly at prime phenylpropanoid alpha C of AL, or in prime ring phenolic hydroxyl group ortho of AL. However, the dispersion property of short chain sulfonic acid group of lignin is limited to improve, and using the phenolic hydroxyl groups of AL for the sulfonation reaction sites to contain long chain alkyl sulfonic acid in AL, and the dispersion properties of lignin modified polymers containing long chain alkyl sulfonate which have no relevant reports.To explore how to use phenolic hydroxyl groups of AL for sulfonation reaction sites to access the long chain alkyl sulfonic acid groups into AL, and prepared lignin with alkyl sulfonic acid groups and its dispersion performance which do good to broaden the modification of AL and its the application range of lignin product.Using a simple method, we developed a new family of alkyl sulfonic acid modified lignosulfonate(ASLS) which direct sulfonation on the phenolic and alocholic hydroxyl groups of alkali lignin as raw material with 1,4-butylenesulfone as sulfonation agent. Structure characterization confirmed the efficient sulfonation and a sulfonation degree of 3.86mmol/g and Mw was 9900 Da of ASLS3 has been achieved. Furthermore, the structure characterization and application performance were investigated in Poly(3,4-ethylenedioxyth iophene)(PEDOT) dispersed with ASLS3. The results show that the PEDOT: ASLS polymer has the advantages of small particle size, high conductivity, good film forming property, good electro chemical performance and so on. To further explore the effect of dosages of ASLS3 in properties of PEDOT: ASLS polymers, results show that with the increase of ASLS3 dosage, the particle size decreases, room temperature conductivity decreased gradually When m(EDOT)/m(ASLS) was 1, the room temperature conductivity reached 0.0607 mS/cm, which was above the commercial PEDOT.A new family of highly water soluble alkyl chain cross-linked sulfobutylated lignosulfonates(AASLS) with three-dimensional network structure and naked alkyl sulfonic acid groups were readily prepared by using 1,4-BS and C6H12Br2 by one step reaction in water, which simultaneously improved sulfonation degree and molecular weight. Structure characterization confirmed their cross-linked chemical structure and efficient nucleophilic substitution reaction mechanism. Furthermore, the dispersion properties of AASLS3 and AASLS4 in a carbendazim suspension concentrate(SC) system were investigated. AASLS4 with high molecular weights(Mw) and moderate sulfonation degree showed suspensibility of 99% in 45% carbendazim SC after the hot storage at 50 oC for 14 days. Meanwhile, AASLS4 alsoshowed smaller SC particle size and better rheological performance than commercial lignosulfonate. The alkyl chaincross-linked structure and long alkyl chain-containing sulfonic acid groups contribute to the excellent dispersion properties on carbendazim SC.The dispersion properties of AASLS-carbon nanotubes(MWCNTs) suspension system were systematically studied, and the results showed that, when the dosage was 2 wt%, AASLS-MWCNTs suspensions had a higher absorption at 660 nm than that in polyvinyl pyrrolidone(PVP), sodium polystyrene sulfonate(PSS), and with a higher suspension stability. And with a good electrochemical performance, a low box resistance, a quasi reversible redox behaviors. Further using the MWCNTs which was modified by AASLS4 to doped PEDOT to prepare MWCNTs/PEDOT compound. When m(MWCNTs): m(EDOT) was 1: 4, compared with the PEDOT: ASLS, the electrical conductivity was increased the two orders of magnitude, and its electrochemical behavior was regulated.