Double Crosslinking Research Articles

High biocompatible bone screw enabled by a rapid and robust chitosan/silk fibroin composite material

Hydrogel has attracted tremendous attentions due to its excellent biocompatibility and adaptability in biomedical field. However, it is challenging by the conflicts between inadequate mechanical properties and service requirements. Herein, a rapid and robust hydrogel was developed by interpenetrating networks between chitosan and silk fibroin macromolecules. Thanks to these unique networks, the chitosan-based hydrogel exhibited superior mechanical performances. The maximum breaking strength, Young's modulus and swelling ratio of the hydrogel were 1187.8 kPa, 383.1 MPa and 4.5 % respectively. The hydrogel also supported the proliferation of human umbilical vein endothelial cells for 7 days. Notably, the hydrogel was easily molded into bone screw, and demonstrated compressive strengths of 45.7 MPa, Young's modulus of 675.6 MPa, respectively. After 49-day biodegradation, the residual rate of the screw in collagenase I solution was up to 89.6 % of the initial weight. In vitro, the screws not only had high resistance to biodegradation, but also had outstanding biocompatibility of osteoblast. This study provided a promising physical-chemical double crosslinking strategy to build orthopedic materials, holding a great potential in biomedical devices.

A dual network cross-linked hydrogel with multifunctional Bletilla striata polysaccharide/gelatin/tea polyphenol for wound healing promotion

Wound healing is a dynamic and complex biological process, and traditional biological excipients cannot meet the needs of the wound healing process, and there is an urgent need for a biological dressing with multifunctionality and the ability to participate in all stages of wound healing. This study developed tea polyphenol (TP) incorporated multifunctional hydrogel based on oxidized Bletilla striata polysaccharide (OBSP) and adipic acid dihydrazide modified gelatin (Gel-ADH) with antimicrobial, antioxidant hemostatic, and anti-inflammatory properties to promote wound healing. The composite OBSP, Gel-ADH, TP (OBGTP) hydrogels prepared by double crosslinking between OBSP, TP and Gel-ADH via Schiff base bonding and hydrogen bonding had good rheological and swelling properties. The introduction of TP provided the composite hydrogel with excellent antioxidant antibacterial activities against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coil). In the rat liver hemorrhage model and skin injury model, the OBGTP composite hydrogel had significant (p < 0.001) hemostatic ability, and had the ability to accelerate collagen deposition, reduce the expression of inflammatory factors, and promote rapid wound healing. In addition, OBGTP hydrogels had adhesive properties and good biocompatibility. In conclusion, OBGTP multifunctional composite hydrogels have great potential for wound healing applications.

Strong double networked hybrid cellulosic foam for passive cooling

Up to now, energy conservation, emission reduction, and environmental protection are still the goals that humanity continuously pursues. Passive radiative cooling is a zero-consumption cooling technology, which gains more and more attention. However, the contraction between mechanical strength and cooling performance of traditional radiative cooling materials still limits their scalable production. In this work, we developed a strong double-networked hybrid cellulosic foam via crosslinking recyclable CNF and PVA with a silane coupling agent in the freeze-drying process. Meanwhile, nano zinc oxide and MOF were added to improve the mechanical and solar scattering of foam. Benefiting from the synergistic solar scattering of ZnO and MOF and the stable double crosslinking network, the as-prepared hybrid cellulosic foam exhibits high solar reflectivity of 0.965, high IR emissivity of 0.94, ultrahigh mechanical strength of and low thermal conductivity. Based on above results, the hybrid cellulosic foam shows high-performance daytime cooling efficiency of 7.5 °C under direct sunlight in the hot region (Nanjing, China), which can serve as outdoor thermal-regulation materials. This work demonstrates that biomass materials possess the enormous potential of in thermal regulating materials, and also provides great possibilities for their applications in energy conservation, environmental protection and green building materials.

Improved stability and mechanical properties of citrus pectin-zein emulsion gels by double crosslinking with calcium and transglutaminase

The low water solubility of zein severely limits its industrial application. In this study, the emulsifying performance and stability of zein were improved by electrostatically compounding different ratios of citrus pectin (CP) with zein to obtain zein-CP composite particles (ZCPs). When the mass ratio of CP to zein was 1: 2 (C1Z2), the composite particles showed the smallest particle size, and the C1Z2 stabilized Pickering emulsion (C1Z2-PE) exhibited excellent physical and environmental stability. The ZCPs stabilized emulsions were further cross-linked by transglutaminase (TGase) and Ca2+, resulting in the formation of emulsion gels with increased mechanical properties. Macroscopic and microscopic morphology analysis demonstrated the successful preparation of the emulsion gels. Through the rheological study and texture analysis, it was observed that the double cross-linked emulsion gels exhibited a remarkable improvement in apparent viscosity and gel hardness. This research offers a new strategy and technical reference for the development of new gel-based products.

Wearable Microneedle Patch for Colorimetric Detection of Multiple Signature Biomarkers in vivo Toward Diabetic Diagnosis.

Type 2 diabetes is rapidly emerging as a global public health problem. While blood glucose monitoring has been the primary method of managing diabetes for decades, the increasing global prevalence of the disease suggests that there might be a need to identify additional biomarkers for a more precise early diagnosis. Herein, a microneedle patch based wearable sensor is developed for the purpose of diabetic diagnosis. Utilizing methacrylic acid modified gelatin and polyvinyl alcohol in the fabrication of microneedleshas improved their mechanical properties for skin penetration and increased swelling capacity for interstitialfluid extraction, thanks to the double crosslinking mechanism. The fabricated microneedles are further integrated with test paper functionalized with enzyme and dye molecules to detect multiple signature biomarkers of diabetes in vivo through a colorimetric reaction. Such a wearable microneedle patch holds significant promise for the real-time monitoring of various biomarkers related to chronic diseases and aging.

Superabsorbent carboxymethyl cellulose–based hydrogel fabricated by liquid-metal-induced double crosslinking polymerisation

Herein, we introduced a liquid-metal/polymerisable deep eutectic solvent (LM/PDES) system to the carboxymethyl cellulose (CMC) and acrylic acid solution to prepare a double–cross-linked CMC-polyacrylic acid (PAA)-LM/PDES superabsorbent hydrogel via graft crosslinking polymerisation for 5 min. FTIR and XRD provided evidence for the coordinate crosslinking between Ga3+ and carboxy groups in the CMC-PAA-LM/PDES gel structure and chemical crosslinking between CMC and PAA components. The pore size of the obtained hydrogels gradually decreases with the increase of LM-AA/PDES content. The rigid CMC polysaccharide chains increased the distance between the ionic groups on the flexible PAA molecular chains, resulting in high osmotic pressure. In addition, the synergistic effects of hydrophilic groups, electrostatic repulsion, macroporous structures and double crosslinking on the CMC and PAA structures provided a driving force and space for the gel to absorb electrolyte containing liquid. The absorption capacity of the CMC-PAA-LM/PDES gel for physiological saline reached 97 g/g, which exceeded that of a single cross-linked CMC-PAA gel and a reported superabsorbent material (71 g/g). This work solved the problem of long heating times and insufficient mechanical properties for the preparation of superabsorbent gels, providing a theoretical reference for improving the absorption capacity of superabsorbent materials for electrolyte-containing aqueous solutions.

Functionalized pectin/alginate food packaging films based on metal-phenol networks

It was focused on development a film with excellent properties. The pectin/sodium alginate (PS) composite films were developed by a casting technology, incorporating with tannic acid and Fe3+ for double cross-linking, and the effects of the film thickness, optical, mechanical, barrier, and antioxidant properties were investigated. This results displayed the inclusion of tannic acid (TA) and Fe3+ considerably increased the physical aspects, and they were very compatible with the matrix of the PS, exhibiting higher UV barrier capacity and lower gas permeability. On the other hand, the more compact structure observed by SEM as well as the hydrogen bonding interactions between the film components revealed by FTIR spectroscopy and XRD diffraction analyses further confirmed the significant enhancement of the properties. The functionalized coating of TA-Fe3+ demonstrated an improved adhesion and barrier properties, thereby effectively retarding the ageing process of golden passion fruit and this encompassed a decrease in the weight loss and a significant enhancement in water retention capability.

Synthesis, characterization, and antibacterial effect of St. John's wort oil loaded chitosan hydrogel

Hydrogels prepared with natural and synthetic polymers were found to be applicable for the development of resistance against some Gram positive and negative bacterial species. Numerous studies have shown that chitosan polymers can be advantageous to be used in medicine due to their high antibacterial activity. In this study, biocompatible yellow cantorone oil doped hydrogels (chitosan/poly(vinyl alcohol) based) with antimicrobial properties were synthesized. The structural, morphological, swelling and mechanical properties of these biocompatible hydrogels prepared by double crosslinking were investigated and characterized. FTIR spectroscopy showed the appearance of new imine and acetal bonds due to both covalent cross-linking. In vitro cytotoxicity evaluation revealed that hydrogels showed weak cytotoxic effect. In the antimicrobial evaluation, it was determined that the hydrogel containing only chitosan showed better antimicrobial effect against Escherichia coli, Pseudomonas auriginosa, Staphylococcus aureus and Enterococcus faecalis bacteria than the one containing St. John's Wort oil. The antibacterial effect of polyvinyl alcohol/chitosan hydrogel was low. In our wound healing study, chitosan hydrogel loaded with yellow St. John's Wort oil was more effective in reducing wound size.

Film electrode Li1-xMn2O4/C/PAA-c-CMCLi-b-PVDF by double cross-linking for selective extraction of Li+

Because of its excellent stabilities, polyvinylidene fluoride (PVDF) is commonly employed as a binder in electrode fabrication. However, poor adhesion and hydrophilicity limit its applicability. Herein, PVDF as the hydrophobic framework, polyacrylic acid (PAA), and carboxymethylcellulose lithium (CMCLi) composite binders were cross-linked with phytic acid and Li1-xMn2O4/C were used in the formulation. After 100 electrochemical cycles, the film electrode Li1-xMn2O4/C/PAA-c-CMCLi-b-PVDF exhibits excellent adhesion (0.93 N cm−1) and a low capacity fading rate (8.2 %). Furthermore, this film electrode demonstrated a high intercalation capacity (32.14 mg g−1), a short intercalation equilibrium time (within 2 h), and a fast Li+ intercalation rate, which can be attributed to the synergistic effect of electrolyte permeability enhanced by hydrophilic functional groups (–OH and –COOH), dispersibility of electrode material particles improved by high slurry rheology, and the high transport efficiency of –COOH for Li+. These promising results suggest that this double cross-linked Li1-xMn2O4/C/PAA-c-CMCLi-b-PVDF film electrode is suitable for the selective extraction of Li+.

The three-dimensional culture of L929 and C2C12 cells based on SPI-SA interpenetrating network hydrogel scaffold with excellent mechanical properties.

Cell-cultured meat, which is obtained by adsorbing cells on the three-dimensional scaffold, is considered a potential solution to animal welfare issues. Edible and safe cell-cultured meat scaffolds are a key part of its research. Soy protein isolate (SPI) hydrogel has a three-dimensional network structure and has been studied for L929 cell culture because of its non-toxicity and biocompatibility. However, the toughness and mechanical properties of SPI hydrogel are not enough to bear the requirements of cell cultivation. In this paper, sodium alginate (SA) was added to SPI hydrogel, and the interpenetrating network (IPN) technology was used to construct SPI-SA IPN hydrogel by transglutaminase and Ca2+ double crosslinking method. SPI-SA IPN hydrogel has excellent mechanical properties, structural stability and biodegradable performance than SPI hydrogel. The bio-compatibility and degradability of L929 and C2C12 cells on SPI-SA IPN hydrogel were studied by cytotoxicity, trypan blue and living/dead cell staining, and the growth law of the hydrogel as a scaffold for cell culture was analyzed. The results showed that L929/C2C12 cells can proliferate normally and adhere in hydrogel and have good bio-compatibility. L929 cells with size about 20-50µm have better adhesion and growth abilities on SPI-SA IPN hydrogel than C2C12 cells with 100-300µm. Therefore, the SPI-SA IPN hydrogel is non-toxic and supports the growth of cells in the pores of the material. This study provides a reference for the application of SPI-SA IPN hydrogels in vitro cell growth.

Poly(ethylene glycol) Methyl Ether Acrylate-Grafted Chitosan-Based Micro- and Nanoparticles as a Drug Delivery System for Antibiotics.

Nanotechnology is the science of creating materials at the nanoscale by using various devices, structures, and systems that are often inspired by nature. Micro- and nanoparticles (MPs, NPs) are examples of such materials that have unique properties and can be used as carriers for delivering drugs for different biomedical applications. Chitosan (CS) is a natural polysaccharide that has been widely studied, but it has a problem with low water solubility at neutral or basic pH, which limits its processability. The goal of this work was to use a chemically modified CS with poly(ethylene glycol) methyl ether acrylate (PEGA) to prepare CS micronic and submicronic particles (MPs/NPs) that can deliver different types of antibiotics, respectively, levofloxacin (LEV) and Ciprofloxacin (CIP). The particle preparation procedure employed a double crosslinking method, ionic followed by a covalent, in a water/oil emulsion. The studied process parameters were the precursor concentration, stirring speeds, and amount of ionic crosslinking agent. MPs/NPs were characterized by FT-IR, SEM, light scattering granulometry, and Zeta potential. MPs/NPs were also tested for their water uptake capacity in acidic and neutral pH conditions, and the results showed that they had a pH-dependent behavior. The MPs/NPs were then used to encapsulate two separate drugs, LEV and CIP, and they showed excellent drug loading and release capacity. The MPs/NPs were also found to be safe for cells and blood, which demonstrated their potential as suitable drug delivery systems for biomedical applications.

Double crosslinking decellularized bovine pericardium of dialdehyde chondroitin sulfate and zwitterionic copolymer for bioprosthetic heart valves with enhanced antithrombogenic, anti-inflammatory and anti-calcification properties.

Due to the increasing aging population and the advancements in transcatheter aortic valve replacement (TAVR), the use of bioprosthetic heart valves (BHVs) in patients diagnosed with valvular disease has increased substantially. Commercially available glutaraldehyde (GA) cross-linked biological valves suffer from reduced durability due to a combination of factors, including the high cell toxicity of GA, subacute thrombus, inflammation and calcification. In this study, oxidized chondroitin sulfate (OCS), a natural polysaccharide derivative, was used to replace GA to cross-link decellularized bovine pericardium (DBP), carrying out the first crosslinking of DBP to obtain OCS-BP. Subsequently, the zwitterion radical copolymerization system was introduced in situ to perform double cross-linking to obtain double crosslinked BHVs with biomimetic modification (P(APM/MPC)-OCS-BP). P(APM/MPC)-OCS-BP presented enhanced mechanical properties, collagen stability and enzymatic degradation resistance due to double crosslinking. The ex vivo AV-shunt assay and coagulation factors test suggested that P(APM/MPC)-OCS-BP exhibited excellent anticoagulant and antithrombotic properties due to the introduction of P(APM/MPC). P(APM/MPC)-OCS-BP also showed good HUVEC-cytocompatibility due to the substantial reduction of its residual aldehyde group. The subcutaneous implantation also demonstrated that P(APM/MPC)-OCS-BP showed a weak inflammatory response due to the anti-inflammatory effect of OCS. Finally, in vivo and in vitro results revealed that P(APM/MPC)-OCS-BP exhibited an excellent anti-calcification property. In a word, this simple cooperative crosslinking strategy provides a novel solution to obtain BHVs with good mechanical properties, and HUVEC-cytocompatibility, anti-coagulation, anti-inflammatory and anti-calcification properties. It might be a promising alternative to GA-fixed BP and exhibited good prospects in clinical applications.

Injectable hydrogels doped with PDA nanoparticles for photothermal bacterial inhibition and rapid wound healing in vitro.

The difficulty of wound healing due to skin defects has been a great challenge due to the complex inflammatory microenvironment. Delayed wound healing severely affects the quality of life of patients and represents a significant economic burden for public health systems worldwide. Therefore, there is an urgent need for the development of novel wound dressings that can efficiently resist drug-resistant bacteria and have superior wound repair capabilities in clinical applications. In this study, we designed an adhesive antimicrobial hydrogel dressing (GMH) based on methacrylic-anhydride-modified gelatin and oxidized hyaluronic acid formed by Schiff base and UV-induced double cross-linking for infected wound repair. By inserting PDA nanoparticles into the hydrogel (GMH/PDA), the hydrogel has the capability of photothermal conversion and exhibits good photothermal antimicrobial properties under near-infrared (NIR) light irradiation, which helps to reduce the inflammatory response and avoid bacterial infections during the wound healing process. In addition, GMH/PDA hydrogel exhibits excellent injectability, allowing the hydrogel dressings to be adapted to complex wound surfaces, making them promising candidates for wound therapy. In conclusion, the multifunctional injectable GMH/PDA hydrogel possesses high antimicrobial efficiency, antioxidant properties and good biocompatibility, making them promising candidates for the treatment of infected skin wounds.

A novel injectable sericin hydrogel with strong fluorescence for tracing

Hydrogel systems with strong fluorescence, as convenient tracers or bio-probes, have attracted much attention in biomedical engineering. Currently, most hydrogels endowed fluorescent properties due to modifying additional fluorophores. However, these fluorophores owing to photobleaching and toxicity limit the practical applications of hydrogels. Herein, we prepared a novel self-luminescence hydrogel through double crosslinking glutaraldehyde and hydrogen peroxide/horseradish peroxidase (H2O2/HRP) with sericin protein. The double cross-linked sericin hydrogel exhibits strong green and red intrinsic fluorescence which can be excited over a wide range of wavelengths. Moreover, this hydrogel with strong intrinsic fluorescence could penetrate thick pigskin tissue, which has potential application in implantable bio-tracer areas. In addition to the above unique properties, this sericin hydrogel possesses two types of micropore structures with high porosity, swelling properties, pH-responsive degradability, super elasticity, injectability, viscosity, and excellent biocompatibility. The investigation could significantly expand the scope of protein hydrogels in biomedical applications.

High-performance flexible reduced graphene oxide/polyimide nanocomposite aerogels fabricated by double crosslinking strategy for piezoresistive sensor application

Flexible conductive polyimide aerogels used for piezoresistive pressure sensors in harsh environments are often limited by brittleness, structural collapse, low elastic recovery, low sensitivity, and narrow pressure detection range. Herein, we report a simple and green method of ice-templating unidirectional solidification combined with freeze-drying and thermal imidization to obtain a flexible reduced graphene oxide/polyimide (rGO/PI) nanocomposite aerogels with a double crosslinked structure, which achieve a significant transformation of PI aerogels from brittleness to high flexibility. The strong layered structure and dense interlaminar porous network are established by the covalent crosslinking of 1,3,5-triaminophenoxybenzene (TAB) and the hydrogen bonding crosslinking of graphene oxide (GO), imparting the double crosslinked rGO/PI aerogels with unique “porous honeycomb” structure and excellent mechanical properties. Due to the synergistic effect of TAB, rGO, PI, and unidirectional freezing process, the double crosslinked rGO/PI nanocomposite aerogel shows low density (25 mg/cm3), high compression cycle stability (3000 cycles), wide pressure detection range (0–85.1 kPa), extremely short response time (about 129 ms) and excellent environmental resistance (maintaining high structural stability and pressure response even at high temperatures of 180 °C and low temperatures of −50 °C), suitable for detecting various motion signals. It is proved that the elastic double crosslinked rGO/PI nanocomposite aerogels have potential applications serving as candidate materials for piezoresistive sensors and wearable electronic protective equipment in the fields of national defense, military industry, aerospace, and other fields in extreme environments.

Lignin‐Derived Ionic Conducting Membranes for Low‐Grade Thermal Energy Harvesting

AbstractWood‐based ionic conductive membranes have emerged as a new paradigm for low‐grade thermal energy harvesting applications due to their unique andtailorable structures. Herein, a lignin‐derivedionic conducting membrane with hierarchical aligned channels is synthesized viaa double network crosslinking approach. Their excellent thermal stability andsuperior swelling ratio allow their optimization as low‐grade heat recovery technologies. Several vertically aligned nanoscaleconfinements are found in the synthesized membranes, contributing towardenhanced ionic diffusion. Among all the combinations, the membrane comprising69.2 wt.% of lignin and infiltrated with 0.5 m KOH exhibits anexceptional ionic figure of merit (ZTi) of 0.25, relatively higher ionic conductivity(51.5 mS cm‒1), lower thermal conductivity(0.195 W m‒1·K), and a remarkable ionic Seebeck coefficientof 5.71 mV K‒1 under the application of an axialtemperature gradient. A numerical model is also utilized to evaluate theveracity of experimental observations and to gain a better understanding of thefundamental mechanisms involved in attaining such values. These results displaythe potential of lignin‐basedmembranes for future thermal energy harvesting applications and are a new facetin thermoelectric energy conversion which is certain to pave the way forfurther investigations on sustainable ionic conductive membranes.

Quaternized chitosan/oxidized bacterial cellulose cryogels with shape recovery for noncompressible hemorrhage and wound healing

Management of noncompressible torso hemorrhage is an urgent clinical requirement, desiring biomaterials with rapid hemostasis, anti-infection and excellent resilient properties. In this research, we have prepared a highly resilient cryogel with both hemostatic and antibacterial effects by chemical crosslinking and electrostatic interaction. The network structure crosslinked by quaternized chitosan and genipin was interspersed with oxidized bacterial cellulose after lyophilization. The as-prepared cryogel can quickly return to the original volume when soaking in water or blood. The appropriately sized pores in the cryogel help to absorb blood cells and further activate coagulation, while the quaternary ammonium salt groups on quaternized chitosan inhibit bacterial infections. Both cell and animal experiments showed that the cryogel was hypotoxic and could promote the regeneration of wound tissue. This research provides a new pathway for the preparation of double crosslinking cryogels and offers effective and safe biomaterials for the emergent bleeding management of incompressible wounds.

Sustained Release of Diclofenac from Doubly Cross-linked Hydrogels Consisting of Sodium Alginate/Guar Gum/Zinc Oxide

Diclofenac sodium is a widely used drug for muscular pain. However, it is having considerable adverse effects due to its sensitivity to the gastrointestinal tract. To overcome this problem, a popular method is the usage of alginate-based hydrogel as a matrix. Still, the method is far from satisfactory results due to the high swelling of the matrix, which is due to the inherent swelling property of alginate gel and causes burst release of the drug. The current study is aimed at a solution for all these problems, targeting sustained release of the active drug with controlled swelling of the hydrogel matrix. Anovel drug release system based on sodium alginate (SA)/guar gum and zinc oxide nanoparticles, which are doubly cross-linked with calcium chloride and citric acid, was developed. ZnO nanoparticles were made through the direct precipitation method. The obtained gels were characterized by Fourier transform infrared, differential scanning calorimetry, scanning electron microscopy, etc. Cross-linked alginate/guar gum hydrogels act as a stabilizing agent and a matrix for sustained release. Incorporation of nanoparticles is found to be improving the sustained release with a considerable decrease in the degree of swelling. These findings suggest SA/guar gum/zinc oxide hydrogel beads prepared by double cross-linking can be a novel system for loading drugs which are sensitive to the gastro-intestinal tract.. KEYWORDS :Hydrogels, Sustainable release, Controlled swelling, Cross-linking agents, Nnanoparticles

Superparamagnetic Hybrid Nanospheres Based on Chitosan Obtained by Double Crosslinking in a Reverse Emulsion for Cancer Treatment.

Nowadays, the Magnetically Targeted Drug Delivery System (MTDDS) is among the most attractive and promising strategies for delivering drugs to the target site. The present study aimed to obtain a biopolymer-magnetite-drug nanosystem via a double crosslinking (ionic and covalent) technique in reverse emulsion, which ensures the mechanical stability of the polymer support in the form of original hybrid nanospheres (NSMs) loaded with biologically active principles (the 5-Fluorouracil (5-FU)) as a potential treatment for cancer. Obtained NSMs were characterized in terms of structure (FT-IR), size (DLS), morphology (SEM), swelling, and 5-FU entrapment/release properties, which were dependent on the synthesis parameters (polymer concentration, dispersion speed, and amount of ionic crosslinking agent). SEM analysis results revealed that NSMs presented a spherical shape and are homogeneous and separated. Moreover, NSMs' ability to load/release 5-FU was tested in vitro, the results confirming, as expected, their dependence on the varied synthesis process and NSM swelling ability in physiological liquids. The drug transport mechanism through the polymer matrix of its release is the Fickian type. The morphological, bio-material characteristics and the ability to include and release an antitumor drug highlight the utility of the NSMs obtained for targeting and treating some tumor diseases.

High solid content waterborne polyurethane and the coatings with double crosslinking structure and multiple hydrogen bonds

The development of coating and emulsion with excellent scratch resistance, friction resistance, high transparency, and yellowing resistance is of great significance for protecting the substrate, reducing the wear of the material, and improving the curing and. drying speed of the coating. Therefore, a double-crosslinked waterborne polyurethane (DCWPU) was prepared in this paper to make up for the shortcomings of slow drying speed and poor toughness of the coating film in a single cross-linked system. Meanwhile, DCWPU utilizes chemical bonding crosslinking network and high-density hydrogen bonding array to cooperate with each other, which is beneficial to improve the mechanical properties of the double-crosslinking system. Herein, 3 (2-hydroxyethyl) isocyanurate (THEIC) was introduced as the intramolecular crosslinking agent, and isophorone isocyanate trimer (IPDI-3), which has the same keto azocyclic structure as THEIC, was added as the post crosslinking agent to further increase the crosslinking degree of the system. The effects of cross-linked monomer content in waterborne polyurethane on scratch resistance, friction resistance, and corresponding emulsion solid content of the coating were studied in the work. It was found that with the increase of double cross-linked monomer content, the hydrogen bond force could be effectively improved, and the mechanical properties, wear resistance and solid content of the emulsion could be significantly improved. It is worth mentioning that DCWPU-3 showed the best comprehensive properties. The emulsion solid content was 48.9%, the tensile strength of the film was increased to 21.8 MPa, the elongation at break was 627.2%, the hardness was 4 H, and the wear amount was 1.2 mg.