Reactivity Of Lignin Research Articles

Influence of Oxygen Exposure on Lignin Preservation during Sediment Lateral Transport in the Ocean: Insights from Molecular Dynamics Simulations.

Understanding the fate of terrestrial organic carbon (terrOC) preservation in the marine environments is critical for deciphering the biogeochemical processes associated with the global carbon cycle and the Earth's climate change. The mechanisms controlling terrOC preservation are not completely understood, while lateral oxygen exposure time (OET) is considered as a critical controlling factor. Here, we first utilized molecular dynamics simulations to investigate the structural properties of lignin under anoxic, suboxic, and oxic conditions for understanding the mechanisms of terrOC preservation during sediment lateral transport in the ocean. Our finding suggested that oxygen exposure was indispensable for terrOC degradation through influencing the structural stability and reactivity of lignin. Our simulated results showed that in suboxic environments, prolonged OET may enhance terrOC preservation. Our organic geochemical results suggested that terrOC preferably preserved in coarse silts (20-63 μm) than fine silts (<20 μm) in suboxic environments, largely due to hydrodynamics-driven prolonged OET in coarse sediments, which may efficiently reduce CO2 emissions. Overall, our study sheds new light on the mechanisms of lateral OETs on terrOC preservation in suboxic conditions and, from a unique molecular structural perspective, provides insights into the impact of prolonged OETs on terrOC oxidative degradation in the marine environment.

Uniformly dispersed Co-Corrin/C catalysts for the study of β-O-4 bonding activity in lignin

In this study, Co-Corrin/C catalysts with corrin active skeleton were prepared by pyrolysis under anaerobic conditions using vitamin B12 (VB12) as a precursor and activated carbon with rich mesoporous structure as a carrier. The Co-Corrin/C catalyst was applied to the oxidative cleavage reaction of lignin, showing a 92.74 % breakage of β-O-4 bonds. Density functional theory (DFT) calculations indicate that the low energy gap difference of Co-Corrin/C promotes electron transfer between Co and O. Meanwhile, the pyrrole ring in the corrin structure will be adsorbed and bonded to oxygen, which promotes the generation of large amounts of oxygen free radicals. The Cα-OH bond in the lignin aliphatic chain is oxidized to Cα=O bond under the action of oxygen radicals, which reduces the dissociation energy of the β-O-4 bond and significantly improves the oxidation efficiency. Cycling experiments proved that Co-Corrin/C has good stability.

Effect of bone char catalyst on the pyrolysis behavior and crystal structure of cotton stalks

This study investigated the characteristics of bone char (BC) in the in situ catalytic pyrolysis of cotton stalk (CS) using a fixed-bed pyrolysis system at 600 °C. The results revealed that BC contained abundant pore structures and polar active sites, which prolonged the residence time of gases and provided numerous reaction sites for the secondary reaction of pyrolysis products. At a CS-to-BC mass ratio of 1:2 (CB-1:2), the reaction rate was accelerated. As the BC proportion increased, the crystallinity of the char decreased, while the specific surface area increased. At CB-1:2, both the crystallite size and crystallinity of BC improved. The oxygen-containing functional groups in BC, such as CO32−, PO43−, −COOH, and −OH, effectively increased the adsorption active sites. Additionally, Ca2+ in BC promoted dehydrogenation, deoxidation, fused cyclization, and decarboxylation of carboxylic acids, leading to increased production of H2, CO, and CO2. Moreover, Ca2+ facilitated the homolytic reactions of lignin, generating hydrogen free radicals. These radicals reacted with methoxy radicals formed during lignin decomposition to produce methane.

Chemical characterization of heat‐treated kraft lignin after fractionation with organic solvents and pH effect

AbstractLignin, the main source of renewable aromatics, has a complex structure, high polydispersity, and low reactivity, which hinders its large‐scale use. This study aims to improve lignin reactivity through heat treatment combined with fractionation by organic solvents or the pH effect. Heat treatment of commercial hardwood black liquor was performed at 225 °C for 150 min. The samples were then fractionated either by using organic solvents (ethyl acetate, ethanol, methanol, and acetone) or by lowering pH using hydrochloric acid (HCl) (pH values 1, 3, 5, 7, and 9). The fractionation was carried out in one step and in sequential mode. The fractionated samples were characterized chemically by the content of acid‐soluble and acid‐insoluble lignin, carbohydrates, ash, inorganic compounds (metals), elemental analysis, and by pyrolysis‐gas chromatography–mass spectrometry (Py‐GC–MS). The highest mass yields were obtained using the one‐step mode for both fractionations, with yields as high as 53.3% for organic solvents and 47.8% for the pH effect. Solvent fractionation reduced ash content by up to 75.4% and increased calorific value, carbon content, and total lignin content. Fractionation by pH effect showed an ash reduction of up to 55.9% and an increase in calorific value and carbon content of up to 8.7 MJ kg−1 and 49.7%, respectively. The Hansen solubility parameters were also calculated to address lignin's solubility in each of the tested solvents. These findings indicate that combining heat treatment and fractionation techniques improves lignin's chemical properties significantly, making it a more viable raw material for industrial use. This approach supports the circular economy by transforming lignin into a high‐value product, thereby promoting sustainable and efficient resource utilization across industries.

Research Status of Lignin-Based Polyurethane and Its Application in Flexible Electronics.

Polyurethanes (PU) have drawn great attention due to their excellent mechanical properties and self-healing and recyclable abilities. Lignin is a natural and renewable raw material in nature, composed of a large number of hydroxyl groups, and has a great potential to replace petroleum polyols in PU synthesis. This review summarizes the recent advances in modification methods such as the liquefaction, alkylation, and demethylation of lignin, and a systematic analysis of how to improve the reactivity and monomer substitution of lignin during polyurethane synthesis for the green manufacturing of high-performance polyurethanes was conducted. Polyurethane can be used in the form of films, foams, and elastomers instead of conventional materials as a dielectric or substrate material to improve the reliability and durability of flexible sensors; this review summarizes the green synthesis of polyurethanes and their applications in flexible electronics, which are expected to provide inspiration for the wearable electronics sector.

Advancing Lignocellulosic Biomass Fractionation through Molten Salt Hydrates: Catalyst-Enhanced Pretreatment for Sustainable Biorefineries.

Developing a process that performs the lignocellulosic biomass fractionation under milder conditions simultaneously with the depolymerization and/or the upgrading of all fractions is fundamental for the economic viability of future lignin-first biorefineries. The molten salt hydrates (MSH) with homogeneous or heterogeneous catalysts are a potential alternative to biomass pretreatment that promotes cellulose's dissolution and its conversion to different platform molecules while keeping the lignin reactivity. This review investigates the fractionation of lignocellulosic biomass using MSH to produce chemicals and fuels. First, the MSH properties and applications are discussed. In particular, the use of MSH in cellulose dissolution and hydrolysis for producing high-value chemicals and fuels is presented. Then, the biomass treatment with MSH is discussed. Different strategies for preventing sugar degradation, such as biphasic media, adsorbents, and precipitation, are contrasted. The potential for valorizing isolated lignin from the pretreatment with MSH is debated. Finally, challenges and limitations in utilizing MSH for biomass valorization are discussed, and future developments are presented. Cellulose Avicel®PH-101 ZnCl2 ⋅ 4H2O, ZnBr2 ⋅ 4H2O, LiCl ⋅ 8H2O, LiBr ⋅ 4H2O H2SO4, (0.2 M); H3PW12O40 (0.067 M); H4SiW12O40 (0.05 M) T (145-175 °C); Time (30-120 min) Organic solvent (MIBK) LA (94 %) and HMF (3.4 %) Dissolution time: ZnBr2 ⋅ 4H2O<>2O<>2 ⋅ 4H2O<>2O; The highest conversion of pretreated cellulose and yield of glucose were obtained with ZnBr2 ⋅ 4H2O (88 % and 80 %, respectively).

The Synergetic Reduction of the Condensation Degree of Dissolved Lignin (DL) during the Refining Process of Wheat Straw Biomass Based on the MA/O3 System.

Lignin, a natural pol2ymer with a complex structure that is difficult to separate, is prone to C-C bond condensation during the separation process. To reduce the condensation of lignin, here, a novel method is proposed for separating the components by using a combination of maleic acid (MA)/ozone (O3) to co-treat wheat straw. The removal of lignin, glucan, and xylan was 38.07 ± 0.2%, 31.44 ± 0.1%, and 71.98 ± 0.1%, respectively, under the conditions of ball-milling of wheat straw for 6 h, reaction temperature of 60 °C, and O3 holding time of 9 min. Lignin-rich solutions were collected to extract the dissolved lignin (DL) after washing the treated samples. The DL obtained under MA/O3 conditions had a carboxyl group (-COOH) content of 2.96 mmol/g. The carboxyl group of MA underwent esterification with the hydroxyl group (-OH) at the γ position of lignin and O3 reacted on the positions of the lignin side chain or the phenolic ring, resulting in a break in the side chain and the opening of the phenolic ring to introduce the carboxyl group. The 2D-HSQC-NMR results revealed that the phenolic ring-opening reaction of lignin in the presence of O3 was essentially free of β-β and β-5 condensation bonds.

The effect of hydrogen bonds on the reactivity of coniferous and deciduous dioxan lignins

The slightly altered samples of dioxan lignin were extracted from coniferous (spruce and juniper) and deciduous wood (aspen) by the Pepper’s method. Lignins were characterized by data of elemental, functional composition, macromolecular and reactive (acid–base and redox) properties. IR spectra of lignins were recorded by the attenuated total refection method. The absorption band of lignins in the 3000–3700 cm−1 region corresponds to the valence vibrations of hydroxyl groups involved in hydrogen bonds. This band was divided into separate Gaussian contours by deconvolution method. The characteristic parameters (energy, length, and relative content) were calculated on the basis of correlation dependencies for each type of H-bonds. The relationship between reactivity (acid–base and redox properties) and the involvement of hydroxyl groups of a natural polymer in H-bonds was shown. The highest reactivity of aspen lignins is caused by the presence of syringyl structures and lower H-bond energies involving reaction centers of macromolecules.

Solvent-Free Lignin-Silsesquioxane wood coating formulation with superhydrophobic and Flame-Retardant functionalities

There is a tremendous motivation to develop eco-friendly formulas for superhydrophobic and flame-retardant coatings. Presently used coating materials, particularly fluorinated compounds and their organic solvents, are potentially toxic. Here, we demonstrate that a silsesquioxane-grafted kraft lignin (WSL) and aluminum phosphate (AP) binder, i.e., an aqueous sustainable formula, can produce a flame retardant and superhydrophobic coating that is highly resistant to water and solvents. The chemical reaction of softwood kraft lignin (SKL) and aminopropyl/methyl silsesquioxane (WAPMSS) was studied comprehensively. NMR and XPS analyses confirmed the conversion of hydroxyl groups of SKL to Si-O-C via polycondensation. The product exhibited negligible wettability and was very hydrophobic. The dip coating of stain-grade pine wood species in the best formula containing WSL and AP dispersion (1/1 wt./wt.) rendered wood with superhydrophobic (with a water contact angle of (WCA) of 158°) and flame-retardant (with a limited oxygen index (LOI) of 27.2 %) functionalities. The exposure of coated wood to different liquids and high temperatures, as well as abrasion, touching, and knife-cutting analyses, confirmed the excellent durability of the coating formulation on wood. This paper demonstrates an eco-friendly pathway to produce a sustainable wood coating formulation with superhydrophobic and flame-retardant features.

Two approaches to prepare cationic lignin‐based adsorbents for efficient removal of phosphate ion from wastewater

AbstractIn this work, two types of cationic lignin‐based adsorbents (AL‐METAC and AL‐GTA) were prepared through free radical polymerization or etherification reaction of alkali lignin with 2,3‐epoxypropyl‐3‐trimethylammonium chloride or methylacrylloxyethyl trimethyl ammonium chloride (METAC). The contents of quaternary ammonium groups in the adsorbents were adjusted by changing the dosages of 2,3‐epoxypropyl‐3‐trimethylammonium chloride and METAC to fabricate the adsorbents with excellent adsorption capacity. The structures, aqueous solubility, and physical properties of adsorbents were analyzed. Meanwhile, the effects of adsorbents dosage, pH value of solution, temperature, and ionic strength on the adsorption capacity of adsorbents were also analyzed. These two types of adsorbents exhibited outstanding affinity for phosphate, with a maximum removal efficiency of 51.8 and 73.2 mg/g, respectively. The adsorption processes followed pseudo‐second‐order and Langmuir models well. In addition, the AL‐GTA exhibited higher removal efficiency than AL‐METAC. Moreover, the AL‐METAC and AL‐GTA still retained 69.7% and 69.0% adsorption capacity after four times regeneration. The fabricated lignin‐based adsorbents have potential applications in the removal of phosphate from wastewater, which would promote the high‐value application of lignin.

Effect of traditional solvent on thermal decomposition mechanism of lignin: A density functional theory study

In order to understand the effect of traditional solvents on lignin pyrolysis, the decarbonylation and decarboxylation reactions of various phenylic lignin model compounds were theoretically investigated using DFT methods at M06-2×/6–31++G(d,p) level. The calculation results show that activation energy of the decarbonylation and decarboxylation reactions of lignin model compounds can be reduced when H2O/CH3OH existed. There are two types of reaction for the H2O/CH3OH during the pyrolysis. For first type, the synergistic reaction of lignin with H2O/CH3OH as hydrogen transfer carrier. The energy barriers of the main elemental reaction steps during this type of pyrolysis are about 285.0–300.0 kJ/mol (H2O) and 275.0–290.0 kJ/mol (CH3OH) (decarbonylation), 170.0–210.0 kJ/mol and 155.0–200.0 kJ/mol (decarboxylation). For another type, the synergistic reaction of lignin with H2O/CH3OH as hydrogen source. The energy barriers of the main elemental reaction steps during this type of pyrolysis are about 260.0–278.0 kJ/mol and 240.0–260.0 kJ/mol, 303.0–312.0 kJ/mol and 291.0–297.0 kJ/mol. Furthermore, the reaction temperature has the most significant impact on decomposition reaction of lignin in a methanol medium, suggesting that the reaction in the methanol medium is better than that in the water environment.

Preparation and Structural Analysis of a Water-Soluble Aminated Lignin.

Lignin is insoluble in water, thereby limiting its use in the synthesis of adhesives. Therefore, in this study, an aminated lignin compound was prepared through a lignin amination reaction to increase the amount of raw lignin material that can be used in the synthesis of adhesives; moreover, structural analysis was conducted. The main result of this was the introduction of amino groups into phenolic hydroxyl groups in the hydrolyzing lignin from the raw lignin materials, thus generating the product of aminated lignin. The resulting particle sizes were about 100 nm, the average molecular weight was 57,627 g/mol, and the water solubility of the aminated lignin was about 0.45 g/100 mL. Therefore, the water solubility of raw lignin was greatly improved. The proposed reaction mechanism of phenolic hydroxyl groups and carboxylic acid groups in lignin is a reaction with ammonia molecules; thus, the successful introduction of amino groups generated the aminated lignin compounds. Hence, this article enriches the scientific theory of lignin reactions and provides a reference for the widespread application of raw lignin materials in the field of adhesives.

Acid-catalyzed phenolation of lignin with tea polyphenol: Enhancing uv resistance and oxidation resistance for potential applications

The rapid development of the industry has led to the destruction of the earth's ozone layer, resulting in an increasingly serious problem of excessive ultraviolet radiation. Exploring effective measures to address these problems has become a hot topic. Lignin shows promise in the design and preparation of anti-ultraviolet products due to its inherent properties. However, it is important to investigate way to enhance the reactivity of lignin and determine its application form in related products. In this study, phenolic reactions with tea polyphenols were conducted through acid-catalyzed conversion, utilizing organic solvent lignin as the primary material. The phenolic hydroxyl content of the original lignin increased significantly by 218.8 %, resulting in notable improvements in UV resistance and oxidation resistance for phenolic lignin. Additionally, micro-nanocapsule emulsions were formed using phenolic lignin particles as surfactants through ultrasonic cavitation with small-molecule sunscreens. A bio-based sunscreen was prepared with phenolated lignin micro-nanocapsules as the active ingredient, achieving an SPF 100.2 and demonstrating excellent stability. The sunscreen also exhibited strong antioxidant properties and impermeability, ensuring user safety. This research offers a current solution for improving the application of lignin in sunscreens while also broadening the potential uses of plant-based materials in advanced functional products.

Lignin phenolation by graft copolymerization to boost its reactivity

Lignin is the most abundant phenolic biopolymer and a renewable resource of aromatics. It can be used as a phenol substitute in the synthesis of phenolic resins. However, lignin is not as reactive as phenol, so phenolation is generally carried out to improve lignin reactivity. In this work, we suggest a solution to circumvent the limitations of traditional phenolation (e.g., high temperature, strong acids/bases, limited reactivity, and phenol toxicity). We first attempt new lignin phenolation by graft copolymerization in which polymeric phenol, instead of toxic phenol, is introduced to lignin. Organosolv lignin from hardwood was modified with 2-bromoisobutyryl bromide to act as a lignin macroinitiator (L-Br). A protected phenolic monomer, 4-acetoxystyrene, was graft copolymerized onto L-Br using CuBr2/tris[2-(dimethylamino)ethyl]amine as a catalyst/ligand, after which the resultant lignin copolymer was deacetylated to produce lignin grafted with poly(4-hydroxystyrene). This poly-phenolation process was conducted at room temperature without the strong acids/bases and toxic phenol required in conventional phenolation. The poly-phenolated lignin was analyzed using 1H-, 13C-, and 31P NMR spectroscopy and gel permeation chromatography. This novel phenolation process enhanced the reactive sites of lignin more than tenfold. It also reduced the dark color of technical lignins significantly, thereby overcoming a serious obstacle to their applicability.

Cellulose first fractionation strategy in lignin valorization: A mini review

Lignin, a naturally abundant aromatic polymer of natural origin, offers numerous desired intrinsic properties belonging to rich functional groups. However, the lignin properties vary influenced by the source of biomass (hardwood, softwood, and herbaceous) with different monomer unit proportions, delignification methods, and isolation techniques. To extract lignin, two routes have been introduced i.e. cellulose first fractionation and lignin first fractionation. The focus of this review is revisiting the strategy of cellulose first fractionation in which lignin is mainly present as a side product of the delignification process via the sulfur-bearing process and the non-sulfur-bearing process. After that process, the isolation process was employed in black liquor as a by-product of the process. By this route, technical lignin is produced with the potential to convert into biomaterial feedstocks. The main property concern of this lignin is its condensed structure which requires further modification for specific purposes. Physical and chemical modification can be introduced to increase the reactivity of lignin to widen the application

Preparation and characterization of lignin-derived carbon aerogels.

Lignin is considered a valuable renewable resource for building new chemicals and materials, particularly resins and polymers. The aromatic nature of lignin suggests a synthetic route for synthesizing organic aerogels (AGs) similar to the aqueous polycondensation of resorcinol with formaldehyde (FA). The structure and reactivity of lignin largely depend on the severity of the isolation method used, which challenges the development of new organic and carbon materials. Resorcinol aerogels are considered a source of porous carbon material, while lignin-based aerogels also possess great potential for the development of carbon materials, having a high carbon yield with a high specific surface area and microporosity. In the present study, the birch hydrolysis lignin and organosolv lignin extracted from pine were used to prepare AGs with formaldehyde, with the addition of 5-methylresorcinol in the range of 75%-25%, yielding monolithic mesoporous aerogels with a relatively high specific surface area of up to 343.4m2/g. The obtained lignin-based AGs were further used as raw materials for the preparation of porous carbon aerogels (CAs) under well-controlled pyrolysis conditions with the morphology, especially porosity and the specific surface area, being dependent on the origin of lignin and its content in the starting material.

Cationic lignin as an efficient and sustainable homogenous catalyst for aqueous Knoevenagel condensation reactions.

Knoevenagel condensation is a chemical reaction between aldehydes and active methylene-containing compounds in the presence of heterogeneous, basic homogenous organic or inorganic catalysts and solvent or neat systems. Herein, we introduced a new strategy for this synthesis by using the aqueous solution of cationic kraft lignin (CKL) as a catalyst. The CKL was synthesized through the reaction of kraft lignin (KL) with glycidyltrimethylammonium chloride (GTMAC) in a basic medium. The optimal reaction conditions for the Knoevenagel reaction were 5% catalyst load (weight of catalyst to the weight of benzaldehyde), water as the solvent, and at room temperature, which generated the products with a yield of 97%, illustrating that the CKL was an effective homogenous and green catalyst. The results confirmed that the increase in CKL charge density improved the product yield. The water-insoluble products were easily separated by filtration, and the filtrate containing the catalysts was reused effectively for 5 cycles without a significant decrease in the production yield, which would confirm the advantages of this catalyst for this reaction system. The CKL catalyst exhibited biodegradability comparable to KL. This paper discusses a novel method for Knoevenagel condensation reactions for different aldehydes in a green system utilizing a sustainable, biodegradable catalyst at room temperature and in an aqueous system.

UV irradiation behavior of Salix psammophila sand barriers in the process of desertification control.

Salix psammophila sand barriers degrade under sunlight exposure, resulting in diminished protective performance and shortened service life in desertification control. To address the unresolved issue of photoinduced damage and degradation in sand barriers, we conducted simulations to assess the accelerated damage effect of ultraviolet (UV) rays during solar exposure of S. psammophila sand barriers. Our analysis focused on elucidating the mechanism of UV irradiation in sand barriers by examining the structural and material property changes that occur during the degradation process. The results indicated the following: (1) The discoloration of sand barriers resulting from UV irradiation was primarily ascribed to the modification in lignin content. (2) The morphology and protective performance of S. psammophila sand barriers underwent significant changes following exposure to UV irradiation. The 96-day and 144-day time points of UV exposure are crucial for evaluating the extent of UV degradation in sand barriers. After 192 days of UV irradiation, there was a decrease in mass loss percentage by 3.62%, modulus of elasticity by 8.63%, and modulus of rupture by 6.74%. (3) The lignin, hemicellulose, and cellulose content decreased by 23.12%, 14.30%, and 6.96%, respectively. The impact of UV irradiation on the polysaccharide (cellulose and hemicellulose) in S. psammophila sand barriers was relatively minimal. (4) The carbon binding form in S. psammophila sand barriers underwent a transformation, characterized by a significant decrease in C1 content and an increase in C2 and C3 content. This resulted in a gradual enhancement of the oxidation state and binding energy of carbon. Therefore, to prolong the utilization lifespan of S. psammophila sand barriers, it is essential to address the UV irradiation behavior from the perspective of inhibiting lignin reactions.

Kraft Lignin Electro-Oxidation under Ambient Temperature and Pressure

Lignin is the largest natural source of aromatic chemicals. Due to its complex polymeric structure, Kraft lignin is under-utilized and usually combusted for heat generation, thus resulting in CO2 emissions in the Kraft process. To valorize lignin with renewable electricity and to convert it into value-added aromatic chemicals, efficient electrochemical methods need to be discovered, based not only on its apparent yield of building block chemicals but also on its energy efficiency. In this study, the electro-oxidative performance of six different metals was systematically evaluated. The results showed that the synthesized Ni-based catalyst can increase the vanillin and vanillic acid apparent yield by 50–60% compared to when Ni-based catalyst is absent. We also found that the oxygen evolution reaction (OER) is more than a competing reaction since the presence of oxygen synergistically aids oxidation of the lignin to increase aromatic chemical production by 63% compared to the sum of vanillin generation from both voltage-only and oxygen-only scenarios. With the novel proposed notion of charge efficiency, we showed that utilizing a thinner layer of Ni catalyst balances the OER and the oxidative reaction of lignin, thus improving the charge efficiency for vanillin by 22%

Lignin demethylation enabled robust and reprocessable bio-polyurethane elastomer with adaptable cross-linking network

The development of sustainable bio-polyurethanes (bio-PU) from nonfood lignin has been attracting extensive attention owing to the abundant reserves, stable aromatic structures, and rich hydroxyls of lignin. However, exploiting a high-performance lignin-based PU integrating excellent mechanical properties with reprocessability is still a challenge. Herein, we proposed a dynamic phenolic-carbamates to construct robust and reprocessable bio-PU elastomers based on the reaction of phenolic lignin (PL) with isocyanate. Benefiting from the low Mw of 1692 Da and the abundant phenolic hydroxyls of 8.3 mmol/g, the adaptable cross-linking network consisting of dynamic hydrogen bonds and phenolic-carbamates were formed by PL. The synthesized phenolic lignin-based PU (PLPU) displayed tunable mechanical properties via adjusting PL substitution amount. The tensile strength, modulus and toughness of PLPU reached 58.8 MPa, 1350.3 MPa, and 57 MJ/m3 when the substitution amount of PL was 70%, respectively. Importantly, the reversible cross-linking structure endowed PLPU with excellent multi-reprocessability. After 5 reprocessing cycles, the retention ratio of strength, breaking elongation, modulus and toughness was 87.6%, 58.9%, 218.1% and 63.3%, respectively, which were 1.6, 1.1, 3.5, 2.2 times higher than those of commercial lignin-based polyurethane (CLPU). Therefore, this work not only presents a robust and multi-reprocessable lignin-based PU elastomer with high substitution amount, but also provides a promising sustainable alternative to replace petroleum-based plastic.