Lignosulfonate Research Articles

The anticorrosive applications of anionic surfactant on AA2024-T3 aluminum alloy in alkaline medium: Experimental and theory

Inhibitory effects of sodium abietate (SA) and sodium lignin sulfonate (SLS) were discussed using a series of tests and theoretical calculations. Experimental outcomes obtained via weight loss and electrochemistry data showed that SA and SLS significantly inhibited the corrosion of AA2024-T3 Aluminum alloys in NaOH media. The inhibition efficiency (η%) for SA and SLS was up to 96.02% and 98.82% at 5 × 10−3 mol·L−1, respectively. SA and SLS acted as anode-dominated mixed-type inhibitors in aggressive solutions as recorded by electrochemical methods. In addition, the surface analyses further corroborated the protection of the metal surface from corrosion as added with SA and SLS that can form an adsorbed film on the metal surface. The adsorption obeyed Langmuir isotherm which illustrated the adsorptions of the SA and SLS were a mix of physical and chemical adsorptions. Moreover, the inhibition performance of both inhibitors with the molecular structure shown in quantum chemical calculations and molecular dynamics simulation found that be suitable for explaining the inhibitive action of the two. The study suggests SA and SLS as green sources appropriate for anticorrosive applications.

Selective esterification of glycerol with acetic acid to green fuel bio-additive over a lignosulfonate-based renewable solid acid

Using waste biomass as feedstock to obtain high value-added chemicals has attracted increasingly more attention from the viewpoint of sustainable development. A novel renewable bio-based solid acid (LFuS) was prepared by a two-step sulfonation of the phenol-formaldehyde condensation product of sodium lignosulfonate (LS-Na) and furfural derived from industrial and agricultural organic wastes. LFuS was then firstly employed as a catalyst for the selective esterification of glycerol (GL) with acetic acid (HOAc) to produce a fuel bio-additive, a mixture of glycerol diacetates (DAG) and glycerol triacetate (TAG). Using LFuS achieved a 98.0% conversion of GL with the selectivity to DAG + TAG of 94.1% under milder conditions. Additionally, the obtained LFuS also exhibited an excellent reusability in this reaction, and no loss in glycerol conversion was observed after five cycles, with the corresponding selectivity to DAG + TAG only decreasing from 94.1% to 90.0% after five cycles. The high concentration of acid sites and the polyphenolic structure of LFuS are responsible for its excellent catalytic performance and reusability in selective esterification of glycerol reaction.

Effect of lignin source and initiation conditions on graft copolymerization of lignin with acrylamide and performance of graft copolymer as additive in water- based drilling fluid

In our previous study, as effective and eco-friendly polymer additive in the water-based drilling fluids (WBDFs), lignosulfonate-g-polyacrylamide (LS-g-PAAm) graft copolymers were successfully synthesized and characterized [J. Petroleum Science and Engineering, 171(2018) 484–494]. The aim of this study was to investigate effect of the functional groups (sources) of lignin as well as initiation condition on the chemical modification of lignin via graft copolymerization method. Kraft lignin (KL) extracted from black liquor (as a waste of paper mills) and sulfonated lignin (SL) were used as lignins with the different source and chemical structure. KL and SL were then modified by graft radical copolymerization of acrylamide initiated with thermal or redox initiator. The aliphatic hydroxyl groups were identified as the active sites in the graft copolymerization, where the number of these functional groups in the lignin chain had a significant effect on the progress of the graft copolymerization reaction. Structure of the copolymers was investigated qualitatively and quantitatively using Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1HNMR) spectroscopies. The performance of lignin and lignin-based graft copolymers (with different grafting percentage) as an additive in the water-based drilling fluids (WBDFs) was studied. Before and after hot rolling, rheological properties including apparent viscosity, plastic viscosity, yield point as well as fluid loss were measured in the absence and presence of the salt contamination. In all fluids, except fluids containing unmodified lignin, an increase in apparent and plastic viscosities was observed. Also, thermal stability and resistance to the salt contamination were observed in fluids formulated with the graft copolymers. Best performance was observed for a fluid containing of kraft lignin graft copolymer 1 (KLGC1) where grafting percentage was as high as 452.9 wt%. Also, results showed that higher amounts of the aliphatic hydroxyl functional groups in the KL in comparison with the SL provides higher rate of the reaction progress, leading to a superior performance for use of corresponding graft copolymer as an additive in the WBDFs. The KL-based graft copolymers were able to maintain rheological and fluid loss properties during drilling operations under the hot rolling and salt contamination.

Modification of Paper Surface by All-Lignin Coating Formulations.

All-lignin coating formulations were prepared while combining water-soluble cationic kraft lignin (quaternized LignoBoost®, CL) and anionic lignosulphonate (LS). The electrostatic attraction between positively charged CL and negatively charged LS led to the formation of insoluble self-organized macromolecule aggregates that align to films. The structures of the formed layers were evaluated by atomic force microscopy (AFM), firstly on glass lamina using dip-coating deposition and then on handsheets and industrial uncoated paper using roll-to-roll coating in a layer-by-layer mode. Coated samples were also characterized by optical microscopy, scanning electron microscopy (SEM) coupled with energy dispersive spectroscopy (SEM/EDS), and contact angle measurements. It was suggested that the structure of all-lignin aggregates is the result of the interaction of amphiphilic water-soluble lignin molecules leading to their specifically ordered mutual arrangement depending on the order and the mode of their application on the surface. The all-lignin coating of cellulosic fiber imparts lower air permeability and lower free surface energy to paper, mainly due to a decrease in surface polarity, thus promoting the paper's hydrophobic properties. Moderate loading of lignin coating formulations (5-6 g m-2) did not affect the mechanical strength of the paper.

Performance of SLS Surfactant with Imbibition Methode: Literature Review

Surfactant is one of the injection fluids in the EOR process to increase the remaining oil production in the reservoir. One type of surfactant used is a lignosulfonate surfactant based on lignin. This lignin is found in bagasse, which is obtained by hydrolysis and sulfonation processes so that it becomes a lignosulfonate surfactant product, and is known as Sodium Ligno Sulfonate (SLS). The injection of surfactant solutions into reservoirs has developed in recent years. Although field data is still lacking, most of the laboratory research has given birth to new theories. The performance of a surfactant can be influenced by the IFT value. The IFT value depends on the size and wettability characteristics of the reservoir matrix, gravity can play a role and the rock matrix. To determine the recovery factor of an oil, an imbibition test can be carried out using a particular reservoir of crude oil samples. Based on the literature review, surfactant injection in the reservoir can produce different recovery factor values. Based on the imbibition test, the qualitative wettability test (two-phase separation test and flotation test) showed that the injection of surfactin and STEOL CS-330 could produce different RF. Based on the results of the imbibition test with several rock samples that have fairly good porosity and permeability, it produces varying RF values, the highest value is 1 ml and the lowest is 0.05 ml. Good results as in samples number 23D, number 29D, and 32B, were obtained at different concentrations, possibly due to the swelling clay which resulted in the closure of the porosity and permeability of the rock, it could also be due to a less homogeneous solution.

Lignin nanorods reinforced nanocomposite hydrogels with UV-shielding, anti-freezing and anti-drying applications

Recently, natural polymers with brilliant features such as environment-friendly, biocompatibility, biodegradability and diverse applications, have attracted great attention. As the most abundant natural renewable aromatic polymer, the high-value utilization of lignin recently has become a research hotspot worldwide. In this work, lignin sulfonate nanorods (LSNs) prepared by a facile self-assembly method were creatively introduced into the polyacrylamide/polyacrylic acid (PAM/PAA) network in water/glycerol solvent system to construct a mechanically enhanced, UV-shielding and anti-freezing/anti-drying nanocomposite hydrogel. The fluorescence images of hydrogels showed that LSNs were well-distributed in the hydrogels network and the hydrogen bonds were formed between LSNs and polymer network of hydrogels, which dramatically enhanced the tensile strength and ultimate elongation of hydrogels from 20 to 62 KPa and 210–420 %, respectively. Moreover, hydrogels exhibited good UV blocking performance due to the presence of lignin. Simultaneously, in the presence of glycerol, the nanocomposite hydrogels could tolerate an extreme low temperature (−60 °C) for a week without freezing and keep the initial state after storage at ambient temperature (20 °C, 60 % relative humidity) for 15 days, exhibiting remarkable potential applications under extreme conditions. Therefore, preparing LSNs reinforced hydrogels with UV-blocking and anti-freezing properties would expand their applications in broader fields. LSNs reinforced hydrogels with excellent UV blocking, anti-freezing and anti-drying properties. • A facile self-assembly method to prepare lignin nanoparticles is presented. • Mechanical properties of hydrogel are enhanced by introducing lignin nanoparticles. • Hydrogel shows excellent UV resistance due to the presence of lignin nanoparticles.

Construction of hierarchical porous carbon with mesopores-enriched from sodium lignosulfonate by dual template strategy and their diversified applications for CO2 capture, radioactive iodine adsorption, and RhB removal

Lignosulfonate, as the large-scale by-products from the sulfite pulping, converting them to porous carbon is an alternative potential path. However, most sodium lignosulfonate (LS-Na) derived porous carbon all belonged to the dominated microporous carbon materials, and had poor graphitization degree and low heteroatoms content. Here, a series of hierarchically porous carbon with rich and controllable mesopores were firstly prepared from LS-Na by two dual template strategies. These carbon materials showed high Brunauer-Emmett-Teller (BET) surface areas (SBET) of 230.6–1483.3 m2/g, hierarchical porous structure (mesopore content up to 84.5%), rich heteroatoms (N, O, S) doping (9.22–22.53%), and good graphitization structure. The incorporation of SBA-15 and Ni species as the nano-templates not only brought the unique micro-structure, but also enhanced mesoporous properties. SLS-C had the largest CO2 uptake (206.2 mg/g) due to the largest micropore volume (Vmicro) and ultramicropore volume (Vultra) by micropore filling mechanism. SLS-S-Ni-C possessed effective iodine capacity (∼2.2 g/g) and good recycling (∼90.9%), the adsorption process was based on the dominated physical adsorption, meanwhile, also along with the weak chemical interaction for some iodine molecules by little strong binding sites. SLS-Ni-C had the largest equilibrium capacity of RhB (350.6 mg/g) and the fast adsorption kinetic (about 50 min) due to the large SBET, suitable micro-mesopores size and proportion. This work provided a kind of hierarchical porous carbon from LS-Na by dual template routes, and matched adsorbents for the removal of targeted contaminants.

Reusable hydrogels based on lignosulfonate and cationic polymer for the removal of Cr(VI) from wastewater

In this investigation, absorbent materials based on the polymer poly ([2-(acryloyloxy)ethyl]trimethylammonium chloride) were synthesized by radical polymerization using varying amounts of sodium lignosulfonate (LS) (0.00–30.0 wt%). The chemical composition was corroborated by Fourier transform infrared spectroscopy, and thermogravimetric analysis showed an increase in the thermal stability of the materials with the incorporation of LS. A porous surface with grooves was observed by scanning electron microscopy. In addition, the hydration in water and the removal capacity of hexavalent chromium (Cr(VI)) were tested by evaluating different experimental parameters. A hydration capacity of over 2000% was obtained when the incorporated percentage of LS exceeded 20.0 wt%. A maximum Cr(VI) removal efficiency of 88.4% was obtained by the adsorbent prepared with 5.00 wt% LS. The obtained results were well fit by a pseudosecond-order kinetic model and the Langmuir isotherm model. The presence of chromium on the surfaces of the adsorbents was corroborated. It was also found that the presence of interfering species led to a decrease of up to 11.0% of the maximum retention of Cr(VI) and that the materials could be reused up to five times without a significant decrease in efficiency. The adsorbent material prepared in this research has promising properties for application in the removal of metal anions, which could be extended to various anionic pollutants present in wastewater.

Lignin-derived hierarchical porous carbon with high surface area and interconnected pores for efficient antibiotics adsorption

Biomass-derived porous carbon is a promising antibiotic adsorption material due to its abundant reserves, low cost, and eco-friendly features. However, most biomass-derived porous carbon exhibits undesirable performance in the adsorption of high-molecular-weight antibiotics, which is attributed to the large mass transfer resistance during the adsorption process. Herein, we employ lignosulfonate (LS) as the biomass carbon source and CaCO3 as the activator to fabricate lignin-derived hierarchical porous carbon (LPC-CaCO3) which possesses a high surface area (2944 m2/g) and a large pore volume (1.406 cm3/g). Moreover, we demonstrate uniform mixing and simultaneous pyrolysis of carbon resources and activators are essential to the formation of interconnected pores. Large numbers of connected pores effectively reduce the mass transfer resistance. LPC-CaCO3 exhibits high adsorption capacity to low-molecular-weight antibiotics (sulfamethazine) and high-molecular-weight antibiotics (tylosin) in both batch and column modes. The adsorption performances of LPC-CaCO3 to antibiotics, especially high-molecular-weight antibiotics, are superior to most other reported biomass-derived carbons, commercial activated carbons, and petroleum-derived carbons. This work presents an effective strategy to fabricate a high-performance antibiotics adsorbent from biomass resources and provides deep insight into the structure–activity relationship of porous antibiotics adsorbents.

Fabrication of a Highly Efficient Wood-Based Solar Interfacial Evaporator with Self-Desalting and Sterilization Performance.

Solar interfacial evaporation based on wood-derived materials has been considered a promising strategy for desalination and wastewater purification. Herein, we adopted delignified wood (DW) as the water transport substrate and lignosulfonate (LS)-modified narrow-band gap semiconductor nickel disulfide (NiS2) as the light-absorbing agent (LS-NiS2) to fabricate a high-efficiency evaporator (LS-NiS2@DW). On the one hand, the high absorbance (>95%) within a broad wavelength range and excellent photothermal conversion efficiency of LS-NiS2 endow efficient solar energy utilization. On the other hand, the hydrophilicity of DW facilitates water activation, which results in a lower evaporation enthalpy of LS-NiS2@DW (1274.4 kJ kg-1) than that of pure water. By combining LS-NiS2 and DW, LS-NiS2@DW achieved an evaporation rate as high as 2.80 kg m-2 h-1 under one sun irradiation (1 kW m-2), and the evaporation efficiency reached 87.4%. Notably, LS-NiS2@DW exhibits a high evaporation rate (2.42-2.69 kg m-2 h-1) in simulated seawater for 24 h with no salt crystals formed on the surface. Moreover, LS-NiS2@DW shows high antibacterial activity with about 90% reduction in bacterial survival rate. This work could provide new perspectives for the design of a high-efficiency wood-based photothermal evaporator.

Study on the Strength and Microcosmic Characteristics of C50 High-Performance Concrete (HPC) Containing Manufactured Sands

In this paper, C50 high-performance concrete (HPC) containing manufactured sand was prepared. First, three different gradations of aggregates and three different types of admixtures with significant differences in specific surface area, porosity, and water ratios were used to prepare nine groups of concrete mixtures. Second, the effect of the aggregate gradation and admixture on the workability of fresh HPC and compressive strength of hydration-hardened HPC was investigated. Finally, microscopic tests were conducted to examine the hydration product pore structure (mercury injection porosimeter (MIP)), hydration product surface appearance (scanning electron microscope (SEM)), and element qualitative analysis (energy dispersive X-ray spectrometry (EDS)), and the mechanism of the C50 HPC was discussed. The results show that the types of gradation aggregates and admixtures significantly affect the workability and strength of C50 HPC. When the slump of fresh HPC is specified, the workability of the mixture can be controlled by a homemade high-performance lignin sulfonate water reducer. The aggregate gradation biased toward the median of the gradation curve can be used to prepare the C50 HPC. In this paper, the maximum compressive strength of C50 HPC is 58.3 MPa at 90 days. In addition, the microscopic test results show that the composite compound of C50 HPC has a dense hydration product and a high bond strength interface transition zone (ITZ).

Novel bio-based lignosulfonate and Ni(OH)2 nanosheets dual modified layered double hydroxide as an eco-friendly flame retardant for polypropylene

In this paper, a functionalized layered double hydroxide (LDH-LS@Ni(OH)2) flame retardant was designed and fabricated based on a multi-modifier system consisting of lignosulfonate (LS) and Ni(OH)2 and used as a novel flame retardant for polypropylene (PP). In this multi-modifier system, LS as a compatibilizer and charring agent to improve compatibility and char yield, and Ni(OH)2 was utilized to improve the graphitization of char residual, resulting in a PP/LDH-LS@Ni(OH)2 composite with higher thermal stability. With the addition of LDH-LS@Ni(OH)2 was only 15 wt%, the PP/LDH-LS@Ni(OH)2 composite achieved a limiting oxygen index (LOI) of 30.8% and passed the UL-94 V-0 rating. At the same time, the peak heat release rate (PHRR), total heat release (THR), and total smoke production (TSP) were significantly reduced by 62.7%, 29.5%, and 46.2%, respectively. The flame retardant properties of LDH-LS@Ni(OH)2 were mainly due to the catalytic charring effect of the transition metal elements and the physical barrier effect of the hydrotalcite. More specifically, as a highly efficient flame retardant, LDH-LS@Ni(OH)2 has promising potential in reducing the fire hazards of PP composites.

Nitrate Leaching Mitigation Options in Two Dairy Pastoral Soils and Climatic Conditions in New Zealand.

This lysimeter study investigated the effect of late-autumn application of dicyandiamide (DCD), co-poly acrylic-maleic acid (PA-MA), calcium lignosulphonate (LS), a split-application of calcium lignosulphonate (2LS), and a combination of gibberellic acid (GA) and LS (GA + LS) to reduce N leaching losses during May 2020 to December 2020 in lysimeter field sites in Manawatu (Orthic Pumice soil) and Canterbury (Pallic Orthic Brown soil), New Zealand. In a second application, urine-only, GA only and GA + LS treatments were applied during July 2020 in mid-winter on both sites. Results showed that late-autumn application of DCD, 2LS and GA + LS reduced mineral N leaching by 8%, 16%, and 35% in the Manawatu site and by 34%, 11%, and 35% in the Canterbury site, respectively when compared to urine-only. There was no significant increase in cumulative herbage N uptake and yield between urine-treated lysimeters in both sites. Mid-winter application of GA and GA + LS reduced mineral N leaching by 23% and 20%, respectively in the Manawatu site relative to urine-only treated lysimeters, but no significant reduction was observed in the Canterbury site. Our results demonstrated the potential application of these treatments in different soils under different climate and management conditions.

Synthesis and properties of environmentally friendly double‐network fire fighting gel: Based on natural polymer/industrial solid waste

AbstractIn this paper, a new kind of environmental friendly double‐network gel material was prepared. The first network structure was formed by the graft copolymerization of sodium lignosulfonate (LS) and acrylic acid (AA), and the second network structure was formed by the chelation reaction of sodium alginate (SA) and carbide slag clarified solution (Ca2+). Through an orthogonal experiment, the effects of raw material addition on the compressive strength and apparent viscosity of the gel were analyzed. According to the analysis results, the optimal experimental ratio was obtained, i.e., 2 wt% of LS, 0.25 wt% of SA, 15 wt% of AA, 0.1 wt% of MBA and 0.3 wt% of APS. Furthermore, the structure of the gel are characterized by FTIR, XRD, SEM, XPS, and TG‐DTG, and the results prove that the gel successfully polymerized and a stable three‐dimensional network structure is formed. The results of water absorption experiment disclose that the gel is sensitive to ions and pH, and the water absorption rate reaches 121.25 times. In addition, the results of the air leakage experiment and fire extinguishing experiment show that the gel can effectively cover the surface of crushed coal and densely fill the gaps, demonstrating a good plugging capability and fire extinguishing capability.

Enhancement of sugar release from sugarcane bagasse through NaOH-catalyzed ethylene glycol pretreatment and water-soluble sulfonated lignin

In this work, five different NaOH-catalyzed ethylene glycol (EG) pretreatments together with water-soluble sulfonated lignin (SL) were used for enhancing sugarcane bagasse (SCB) enzymatic digestion. The results showed that the coupling of NaOH and EG into a one-pot pretreatment (10%NaOH/EG) was more beneficial to improve SCB enzymatic hydrolysis than that of single 10%NaOH or EG pretreatment, or the two-step pretreatment of NaOH and EG in different sequence (10%NaOH+EG and EG + 10%NaOH, respectively). The highest glucose yield of this work was 91.2 %, mainly released from the SCB that pretreated with 10%NaOH/EG at 130 °C for 60 min and 72 h enzymatic hydrolysis. The adding of SL into the enzymatic hydrolysis step could significantly lower the cellulase dosage and hydrolysis time from 20 FPU/g and 72 h to 10 FPU/g and 24 h, respectively, meanwhile keeping a high glucose yield of 90.4 %. The characterization of various pretreated or un-pretreated SCB confirmed that the improvement of hydrolysis efficiency of SCB after 10%NaOH/EG pretreatment was closely related to the removal of various components barriers in SCB and the fragmentation of pretreated solid. It can be concluded that the developed NaOH-catalyzed ethylene glycol pretreatment was an efficiency way to enhance the sugar release from SCB.

Evaluation of the influence of sodium and magnesium lignosulfonates on the hydration kinetics of cementitious paste

Motivated by their low cost, lignosulfonate-based water reducers are the most used type of admixture in the concrete industry worldwide. Due to the plurality of types of lignosulfonates (LSs) and the recent update to the Brazilian standard for admixtures for concrete, the objective of this work was to investigate the impact of sodium (Na-LS) and magnesium (Mg-LS) lignosulfonates, raw materials present in the Brazilian market, in pastes and concretes produced with cement type CP II F 40 under different dosages (0.40% and 0.80%). For this, the following tests were performed: adsorption curves, isothermal calorimetry, microanalytical tests (TGA/DTG and DRX), and application in the concrete according to NBR 11768-1 standard. The results showed different hydration evolutions among the pastes produced with these lignosulfonates. As a consequence, despite the similarity in water reduction, it was verified that Mg-LS was more suitable for RA1-R (water reducer-retarder, setting time 120-360 min), while Na-LS was more suitable for RA1 (water reducer, setting time 30-160 min).

Enhanced Mn2+ solidification and NH4+-N removal from electrolytic manganese metal residue via surfactants

Electrolytic manganese metal residue (EMMR) harmless treatment has always lacked a low-cost and quick processing technology. In this study, surfactants, namely tetradecyl trimethylammonium chloride (TTC), sodium dodecyl benzene sulfonate (SDBS), sodium lignin sulfonate (SLS), and octadecyl trimethylammonium chloride (OTC), were used in the solidification of Mn 2+ and removal of NH 4 + -N from EMMR. The Mn 2+ and NH 4 + -N concentrations under different reaction conditions, Mn 2+ solidification and NH 4 + -N removal mechanisms, and leaching behavior were studied. The results revealed that the surfactants could enhance the Mn 2+ solidification and NH 4 + -N removal from EMMR, and the order of enhancement was as follows: TTC ＞ SDBS ＞ OTC ＞ SLS. The NH 4 + -N and Mn 2+ concentrations were 12.3 and 0.05 mg·L -1 with the use of 60.0 mg·kg -1 TTC under optimum conditions (solid–liquid ratio of 1.5:1, EMMR to BRM mass ratio of 100:8, temperature of 20 °C, and reaction duration of 12 h), which met the integrated wastewater discharge standard (GB8978-1996). Mn 2+ was mainly solidified as Mn(OH) 2 , MnOOH and MnSiO 3 , and NH 4 + -N in EMMR was mostly removed in the form of ammonia. The results of this study could provide a new idea for cost-effective EMMR harmless treatment.

3D bioprinted conductive spinal cord biomimetic scaffolds for promoting neuronal differentiation of neural stem cells and repairing of spinal cord injury

Spinal cord injury (SCI) is a terrible injury of the central nervous system for which there is no ideal treatment in clinic so far. The spinal cord biomimetic scaffolds which mimic the shape and structure of native spinal cord tissue, could effectively promote the repair of SCI. However, current biomimetic scaffolds do not mimic the biological functions, especially the electrical conductivity, of spinal cord tissue, which largely limits the therapeutic effect of SCI. In this study, we have developed novel conductive hydrogels based on gelatin methacrylate (GelMA), hyaluronic acid methacrylate (HAMA) and poly(3,4-ethylenedioxythiophene): sulfonated lignin (PEDOT:LS). The incorporation of PEDOT:LS into GelMA/HAMA hydrogel matrix significantly improved the conductivity of the hydrogels. By precisely regulating the light curing time, the conductive hydrogels showed mechanical properties similar to native spinal cord tissues. Then, the conductive biomimetic scaffolds were fabricated by 3D bioprinting, and the neural stem cells (NSCs) encapsulated in the scaffolds exhibited good survival rate (higher than 90%). Compared to the non-conductive scaffolds reported, the conductive scaffolds remarkably promoted neuronal differentiation of NSCs in vitro. In a rat spinal cord complete transection model, the conductive biomimetic scaffold dramatically promoted the recovery of hindlimb motor function. Immunofluorescence staining results further showed that the conductive biomimetic scaffold effectively promoted the regeneration of neurons at the injury site, reduced the deposition of glial scar, and promoted nerve axon regeneration and myelination. Overall, the 3D bioprinting of the conductive spinal cord biomimetic scaffolds developed in this work represents a promising approach for the stem cell-based treatment of SCI.

High-temperature soybean meal adhesive based on disulfide bond rearrangement and multiple crosslinking: Water resistance and prepressing adhesion

The main aim of this work is to prepare a high-temperature soybean meal (HSM) wood adhesive with excellent water resistance and prepressing adhesion to satisfy the requirements of green wood-based composites. Different from traditional complex modification methods, a lignosulfonate (LS)-assisted thiol-grafted polyamide-epichlorohydrin (PAE-SH) reinforced HSM wood adhesive was developed via a simple and novel design. The reduced –SH groups were grafted onto polyamide-epichlorohydrin (PAE) to break the S–S in HSM proteins and prompt a disulfide bonds rearrangement between PAE-SH and protein. LS was then introduced into PAE-SH to induce multiple crosslinking interactions, including cation-π interactions and electrostatic interactions. The generation of the LS-assisted PAE-SH not only contributed to the formation of a stable multiple cross-linked adhesive system for strong cohesion, but also provided a suitable solid content of adhesives for the formation of mechanical nail in plywood veneers. The plywood bonded using the PAE-SH/LS-modified adhesive displayed a wet bonding strength of 1.41 MPa, which is 402.9% higher than that of the neat soybean meal adhesive. It was also showed a prepressing bonding strength of 548 kPa, which is more than twice of the pure HSM-based adhesive (245 kPa), greatly reducing the transportation difficulty of veneers before being hot-pressed. This study provides a novel strategy for preparing a water-resistant protein-based adhesives with great potential for industrial application.

Lignin-based non-crosslinked nanocarriers: A promising delivery system of pesticide for development of sustainable agriculture

Lignin sulfonate (LS), a waste material from the paper pulping, was modified with benzoic anhydride to obtain benzoylated lignin sulfonates of adjustable hydrophilicity (BLS). When BLS was combined with difenoconazole (Di), a broad-spectrum fungicide, lignin-based, non-crosslinked nanoparticles were obtained either by solvent exchange or solvent evaporation. When a mass ratio of 1:5 LS: benzoic anhydride was used, the Di release from Di@BLS5 after 1248 h was ca. 74 %, while a commercial difenoconazole microemulsion (Di ME) reached 100 % already after 96 h, proving the sustained release from the lignin nanocarriers. The formulation of Di in lignin-based nanocarriers also improved the UV stability and the foliar retention of Di compared to the commercial formulation of the fungicide. Bioactivity assay showed that Di@BLS5 exhibited high activities and duration against strawberry anthracnose (Colletotrichum gloeosporioides). Overall, the construction of fungicide delivery nano-platform using BLS via a simple non-crosslinked approach is a novel and promising way to develop new formulations for nanopesticide and the development of sustainable agriculture.