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An amphoteric flocculant, MCC(pAA-co-pDMC) was synthesized through an environmental friendly process. Methacryloxyethyltrimethyl ammonium chloride (DMC) and acrylic acid (AA) were grafted onto the skeleton of microcrystalline cellulose (MCC) in NaOH/urea homogeneous system. Orthogonal tests were carried out to achieve the optimal conditions of the polymerization process. Influential factors, which included reaction temperature, reaction time, molar ratio between MCC, acrylic acid and DMC were investigated. The degree of substitution (DS) of AA and DMC were 0.52 and 1.01 under the optimal synthesis conditions. Turbidity removal efficiency of the product can reach 99.82% for kaolin suspension with the initial concentration of 5.0 g/dm3 under pH 7.0. Structural characterization of FT-IR, XPS and elemental analysis were carried out and further confirmed the successful of the polymerization. Influence factors including flocculant dosage, pH and flocculation time were discussed. In addition, two coagulation-flocculation procedures were carried out to dispose kaolin suspension, results found polyaluminum chloride (PAC) (or CaCl2) and MCC(pAA-co-pDMC) have synergy effect in turbidity removal with a significant dosage decrease at high removal efficiency. MCC(pAA-co-pDMC) coupled with ozonation process was used to treat black-middle effluent from pulp and paper mill and exhibited effective result on decolorization and turbidity removal.

Ionic conductive hydrogel with multifunctional properties have shown promising application potential in various fields, including electronic skin, wearable devices and sensors. Herein, a highly stretchable (up to 2800% strain), tough, adhesive ionic conductive hydrogel are prepared using cationic nanocellulose (CCNC) to disperse/stabilize graphitic carbon nitride (g-C3N4), forming CCNC-g-C3N4 complexes and in situ radical polymerization process. The ionic interactions between CNCC and g-C3N4 acted as sacrificial bonds enabled highly stretchability of the hydrogel. The hydrogel showed high sensitivity (gauge factor≈5.6, 0–1.6% strain), enabling the detection of human body motion, speech and exhalation. Furthermore, the hydrogel based self-powered device can charge 2.2 μF capacitor up to 15 V from human motion. This multifunctional hydrogel presents potential applications in self-powered wearable electronics.

An environmental-friendly lipase induced highly hydrophobic NFC film was fabricated through lipase induced dimethyl adipate (DA) esterification followed by silver nanowires (AgNWs) coating for strain sensor application. Due to the lipase activation, the substitution degree (DS

Hydrogel, especially stimuli responsive hydrogel, has attracted enormous attention due to its unique properties for many applications. Herein, Pd NPs@ CNCs was firstly attained by in situgeneration of Pd NPs onto CNCs, and subsequently incorporated into guar gum-based hydrogel, so that a thermo responsive Pd NPs@ CNCs/ guar gum hydrogel catalytic system was obtained. The sol-gel transition was achieved viaa simple heating/cooling cycle: a sol state was obtained above 70 °C, allowing the catalytic reaction; a gel state was attained below 20 °C, allowing the reuse/ recycling of the Pd NPs. Pd NPs were formed by in situ reduction of PdCl2 in the presence of CNCs so that Pd NPs were loaded onto CNCs surfaces. CNCs acted as stabilizers for the Pd NPs. The TEM image showed that the average size of Pd NPs is ˜3 nm. Subsequently, the Pd NPs@ CNCs composites were loaded into the guar gum hydrogel, based on the boron crosslinking chemistry. The hydrogel exhibited rapid sol-gel transition process upon heating (70 °C) and cooling (20 °C) cycles. The Pd NPs loaded sol-gel transition concept was subsequently applied to the Suzuki coupling reactions between aryl bromides and phenyl boronic acids, and a highly efficient catalytic performance (over 85% yield within 2 h) was obtained. The reuse/recycling of the thermo responsive Pd NPs@ CNCs/guar gum hydrogel catalyst system was investigated. This novel Pd NPs loaded thermo-responsive sol-gel transition concept is a promising new catalytic system.

Contamination of heavy metal in wastewater has caused great concerns on human life and health. Developing an efficient material to eliminate the heavy metal ions has been a popular topic in recent years. In this work, sulfonated cellulose (SC) was explored as efficient adsorbent for metal ions in solution. Thermo gravimetric analyzer (TGA), X-ray diffraction (XRD) and Fourier-transform infrared spectrometer (FTIR) first analyzed the characterizations of SC. Subsequently, effects of solution pH, adsorbent loading, temperature and initial metal ion concentration on adsorption performance were investigated. The results showed that sulfonated modification of cellulose could decrease the crystallinity and thermostability of cellulose. Due to its excellent performance of adsorption to metal ions, SC could reach adsorption equilibrium status within as short as 2 min. In multi-component solution, SC can orderly removes Fe 3+ , Pb 2+ and Cu 2+ with excellent selectivity and high efficiency. In addition, SC is a kind of green and renewable adsorbent because it can be easily regenerated by treatment with acid or chelating liquors. The mechanism study shows that the sulfonic group play a major role in the adsorption process.

Cellulose nanocrystals (CNC) were prepared using acid hydrolysis of cellulose fiber. The CNC modified topo-chemically by grafting of bulky cholesterol moieties which changed subsequent morphology, thermal behavior, lyotropic crystalline properties, and host-guest release behavior. Bond formation between the cellulose nanocrystals surfaces and cholesterol was confirmed by FT-IR and solid-state NMR. The product indicated strong hydrophobic characteristics with an ordered chiral nematic self-assembly. This novel biomaterials were exploited through uptake of folic acid as part of a preliminary host-guest system. The guest molecule released as a function of physiologically relevant pHs was examined.

Graphene oxide (GO) and dialdehyde cellulose (DAC) cross-linked with triethylenetetramine (TETA) to synthesis novel adsorbents in both heterogeneous and homogeneous system (nominated as GTD-1 and GTD-2, respectively). SEM images of GTD-1 exhibited uniform distributed multilayer structure, meanwhile, GTD-2 displayed sponge-like configuration. Compared with GTD-1, GTD-2 possessed higher carboxyl groups density, higher surface area and lower crystallinity index. The adsorption property of both adsorbents was explored, GTD-1 showed an adsorptioncapacities of 65.1 mg/g and 80.9 mg/g for Cu(II) and Pb(II); meanwhile, they were 74.2 mg/g and 91.7 mg/g for GTD-2. Adsorption kinetic and equilibrium data revealed both adsorbents fit pseudo-second-order and Freundlich isotherm model for both Cu(II) and Pb(II) adsorption process. On the other hand, GTD-2 displayed lower reusability compared with GTD-1, this mainly attributed to its lower crystallinity index and the micro-pore morphology was easy to be destroyed during the adsorption process. The possible synthesis mechanism of GTD-2 was also proposed.

Phenylboronic acid-derivatized chitosan (chitosan-PBA) were prepared by grafting small molecules bearing phenylboronic acid groups onto chitosan with N-hydroxysuccinimide (NHS) and N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC) as a coupling reagent pair. Self-assembly multilayer thin films of chitosan-PBA and poly(vinyl alcohol) were subsequently produced under pH control on supporting surfaces, either a silicon wafer or polystyrene latex particles. The driving force of the self-assembly was the ester formation of phenylboronic acid containing polymers with PVA, which can be "turned off" by simple pH control.