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The long-term stability of nano disperse dye slurry is a problem in industry. In this work, high molecular-weight polyether amine-bridged lignosulfonates (PEABLs) were prepared to improve the adsorption strength of dispersants on dye surfaces, and thus the stability of nano disperse dyes. Specifically, the molecular simulation software was firstly used to analyze the adsorption of PEABL on dye surfaces. Then, PEABLs with different molecular weights were synthesized and characterized by adjusting the addition of polyether amine. Next, nano disperse dyes were prepared using PEABLs and the optimum grinding conditions were explored and obtained. Finally, PEABL3 was determined to the optimum dispersant, having a smallest particle size (168 nm) and highest stability, comparable to the commercial Reax 85A dispersant and basically satisfying the demand of nano disperse dyes required in digital transfer printing technology. Quartz crystal microbalance (QCM), atomic force microscopy (AFM) and zeta potential results showed as the molecular weight of PEABL increased, the adsorption amount, adsorbed layer rigidity, adsorption force and absolute zeta potential value all firstly increased due to the enhanced hydrophobic interaction, and then decreased due to the formation of complicated three-dimensional network structures caused by the crosslink of lignosulfonate molecules. A maximum was observed for PEABL3., Competing Interests: Declaration of competing interest There are no conflicts to declare., (Copyright © 2022. Published by Elsevier B.V.)

We prepared super-hydrophobic nanocellulose films using a non-toxic octadecylamine/polydopamine system. Octadecylamine, a low surface energy material, was used to provide hydrophobic alkyl long chains. Polydopamine was produced by dopamine under alkaline conditions, creating an adhesive substance, which reinforced the hydrophobic long chains and increased the surface roughness of nanocellulose. The effects of reagent concentration, reaction temperature, and reaction time on hydrophobicity were then investigated. The results showed that with a 1:1 mass ratio of nanocellulose to octadecylamine, and reacting at 60 °C for 4 h, the contact angle of the obtained composite membrane reached 168.2°. Scanning electron microscope images revealed that the modified nanocellulose had a smaller particle size and more uniform distribution, which effectively improved the hydrophobicity of the nanocellulose. Thus, the green preparation of superhydrophobic films with high-temperature resistance and wear resistance was realized, which contributed to the high-value utilization of nanocellulose., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

To improve the heavy metal adsorption of microcrystalline cellulose (MCC), two successive grafting reactions of silylation by (3-chloropropyl)triethoxysilane (CPTES) and amine-functionalization with metformin HCl were performed and the modified MCC from the first and second steps were denoted as MMCC-1 and MMCC-2, respectively. MMCCs were characterized by fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA) and compared to MCC. The presence of the amine group on the MMCC-2 surface was confirmed by FT-IR analysis. According to the XRD results, the crystallinity index (CI) of MMCC-1 increased very slightly compared to that of MCC that can be attributed to the partial hydrolysis of amorphous parts because of acidic conditions used for MCC silylation but CI of MMCC-2 decreased due to the high temperature and long time in the 2 nd step of modification. TGA revealed the lower thermal stability of MMCC-2 than the corresponding MCC., (Copyright © 2019. Published by Elsevier B.V.)

A novel cationic biosorbent was synthesized by grafting organosolv lignin with GT (also named (2-hydrazinyl-2-oxoethyl)-trimethylazanium chloride, abbreviated as GT) and formaldehyde in an aqueous solution by an eco-friendly way (named QA-g-OL). QA-g-OL was employed as biosorbent to remediate hexavalent chromium polluted water. Research found Cr(VI) removal is a pH-dependence process. It was also found that part of the Cr(VI) was reduced to Cr(III) during the process of adsorption in the range of pH was 2.0 to 7.0. Furthermore, QA-g-OL possess strong absorbability for Cr (VI) in a broad concentration range (from 10 to 100 mg/L). The removal efficiencies of Cr (VI) were 93.40%, 96.70%, 98.78% and 97.84% when initial concentration was 10, 20, 50, 80 and 100 mg/L under optimum pH, respectively. On the other side, the adsorption process exhibited swift equilibrium characteristics, the adsorption equilibrium can be achieved within 10 min. The mechanism of hexavalent chromium removed by QA-g-OL were also discussed, results can be benefit for the application of biomass-based adsorbents in the treatment of hexavalent chromium polluted wastewater., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Two series of amphiphilic antimicrobial copolymers containing ciprofloxacin (CPF) and amine functional groups have been synthesized via free-radical copolymerization. The chemical structures of the different amine groups and the copolymer compositions have been systematically varied to study how the structure of the copolymer exerts an influence on the antibacterial activity. The viability of Escherichia coli in the presence of antimicrobial copolymers was observed by confocal laser-scanning microscopy (CLSM). CLSM as well as atomic-force microscopy (AFM) were applied to visualize changes in morphology of bacteria treated with antimicrobial copolymers and elucidate the antimicrobial mechanism of the antimicrobial copolymers. Morphological changes of bacteria observed via AFM and CLSM demonstrated that the antibacterial mechanism was due to the disruption of the bacterial membrane. The destruction of the cell membrane was also confirmed by the leakage of intracellular components, which had a strong absorbance at 260 nm. The inhibitory process was monitored by UV absorption dynamically.

Acetic acid was one of the main compositions of the pre-hydrolysis liquor (PHL), which was recovered by reactive extraction with triisooctylamine (TIOA) diluted with decanol. Dilution of TIOA played an important role in extracting acetic acid from the PHL. The recovery of acetic acid from the PHL by TIOA was increased from 10.34% to 66.60% with the dilution of TIOA to 20% by decanol at the HAc to TIOA molar ratio of 1, consequently, the equilibrium distribution coefficient KD increased. The effects of time, temperature and pH on the extraction process were also studied. The extraction process was very fast. The acetic acid extraction decreased from 65.13% to 57.34% with the rise of temperature to 50°C from 20°C. A higher pH increased the dissociation of acetic acid, as a result, decreased acetic acid extraction. The hemicelluloses in the PHL were unaffected on the extraction process of acetic acid., (Copyright © 2013 Elsevier Ltd. All rights reserved.)