Extra Cross-linking Research Articles

Tuning Spatially Resolved Shape Memory Effects of Stimuli‐Responsive Macroporous Photonic Crystals

Stimuli‐responsive photonic crystals with patterned microstructures are of great interest in developing reconfigurable nano‐optical devices. Leveraging unconventional all‐room‐temperature shape memory efforts and spatially resolved photopolymerization, herein, a facile method for micropatterning stimuli‐responsive photonic crystals is reported. Macroporous shape memory polymer (SMP) photonic crystals fabricated by colloidal templating can be deformed by cold programming, triggering the disappearance of their original structural colors. Exposure of the deformed samples to UV light through a photomask selectively disables the shape memory capabilities in the UV‐exposed regions. Hidden micropatterns defined by the photomask can be revealed by exposing the colorless SMP films to ethanol vapor, which triggers the shape memory recovery of the “memorized” ordered microstructures and the corresponding structural colors. Extensive nanoindentation experiments indicate that the exposure to UV light increases the crosslinking density and enhances the elastic modulus and toughness of the exposed regions by a factor of ≈2.0 and ≈5.2, respectively. Due to the formation of these extra crosslinks in the deformed configuration, they prevent normal shape memory behavior where the strained polymer chains rearrange from the temporary to permanent configuration when triggered by an external stimulus. This simple micropatterning technology can enable multistimuli‐responsive reconfigurable nanophotonic devices and chromogenic anticounterfeiting labels.

Polydopamine-coated hexagonal boron nitride-based electrochemical immunosensing of T-Tau as a marker of Alzheimer's disease

Alzheimer's disease (AD) is a complex pathological process that is one of the leading causes of dementia globally. The demand for diagnostic tools that are minimally invasive, timely, and accurate is on the rise. Total tau (T-Tau) protein in blood serum is a promising biomarker for predicting early-stage AD diagnosis. In this study, the hexagonal boron nitride (HBN) based immunosensor platform was developed to detect T-Tau in artificial blood serum. After the exfoliation of HBN, its surface was coated with polydopamine (PDA) in alkaline conditions. The Anti-T-Tau was immobilized on a hydrophilic nanocomposite surface using PDA's reactive catechol and quinone groups, eliminating the need for extra crosslinkers. The working electrode surface of the screen-printed carbon electrode (SPCE) was coated with HBN-PDA nanocomposite using the drop-casting method. The biofunctional surface was created by directly immobilizing Anti-T-Tau on the HBN-PDA nanocomposite-modified SPCE. The analytical performance of the HBN-PDA/Anti-T-Tau/T-Tau immunosensor in the presence of T-Tau isoforms was determined through electrochemical measurements. The linear detection range was 1–30 pg/mL with a detection limit of 0.42 pg/mL for T-Tau, which is suitable for detecting T-Tau in the blood serum.

Aging characterization of different nitrile butadiene rubbers for sealing in a pneumatic system: Linking the change of the physicochemical state to the mechanical properties

AbstractNitrile butadiene rubbers (NBR) are widely used in sealing applications, such as O‐rings inside the pneumatic system of the French high‐speed train (TGV). In this application, a strong hardening of the NBRs alters the sealing function. Predicting the evolution of the mechanical properties during service life, especially the material hardening, is therefore a strategic issue to optimize time in maintenance operations of the TGV's pneumatic system. The main goal of this study is to reproduce the aging observed on a train's pneumatic system by performing thermo‐oxidative accelerated aging tests with different commercial nitrile rubbers at several temperatures and up to 2016 h. After achieving similar degradation to specimens aged on trains, aging mechanisms and effects have been investigated through different characterization techniques: infrared spectroscopy, swelling tests, X‐ray fluorescence spectrometry, differential scanning calorimetry, thermogravimetric analysis, and micro‐hardness measurements. The results obtained enabled us to identify and to relate aging mechanisms to aging conditions and to precisely determine and quantify the effects of physicochemical state evolution on the mechanical properties of each NBR considered. Extra crosslinks and oxidative functionalities form in the different elastomers, making them hard and brittle, and thus impacting the sealing function.

Naturally derived dual dynamic crosslinked multifunctional hydrogel for diabetic wound healing

Diabetic wound treatments remain a significant challenge for regenerative medicine due to the unicity of clinical dressings, which lack systemic multifunction with injectability, self-healing ability, moderate tissue adhesion, anti-inflammation and antibacterial abilities, and guidance of tissue repair. Herein, a naturally derived multifunctional hydrogel dressing composed of keratin, protocatechuic aldehyde (PA) and iron ions is fabricated through a simple mixing process, circumventing the use of any extra crosslinking agents or functional modification. Our findings showed that a dual dynamic crosslinked network was constructed through a dynamic thiol-aldehyde addition reaction between thiol groups in keratin and aldehyde groups in PA, and catechol-metal ions coordination bonds between catechol groups in PA and Fe3+, and realized good injectability, mechanical performance, self-healing ability, tissue adhesion and antibacterial properties of the hydrogel. Moreover, the incorporation of phellopterin (PP), a natural compound derived from traditional Chinese herb Angelica dahurica endowed the hydrogel with anti-inflammation properties. The PP-loaded hydrogel shortened inflammation duration and accelerated wound repair in the full-thickness wounds of streptozotocin-induced diabetic mice, notably by promoting macrophage polarization towards anti-inflammatory phenotype and resolving local inflammation. The PP-loaded hydrogel achieved almost wound closure after only 10 days for a diabetic wound of 6 mm in diameter. This study demonstrated that the PP-loaded dynamic crosslinked multifunctional hydrogel had a great potential in the treatment of diabetic wounds.

A self-healing magneto-responsive nanocellulose ferrogel and flexible soft strain sensor

Crosslinks are the building blocks of hydrogels and play an important role in their overall properties. They may either be reversible and dynamic allowing for autonomous self-healing properties, or permanent and static resulting in robustness and mechanical strength. Hence, a combination of crosslinks is often required to engineer the 3D network of hydrogels with both autonomous self-healing and required robustness for strain sensing application; however, this complicates the fabrication of such hydrogels. The facile, yet versatile, approach used in this study is to forgo the use of extra crosslinks and instead rely solely on the properties of magnetic nanocellulose to fabricate a tough, stretchy, yet magneto-responsive, ionic conductive ferrogel for strain sensing. The ferrogel also gives stimuli-free and autonomous self-healing capacity, as well as the ability to monitor real-time strain under external magnetic actuation. The ferrogel also functions as a touch-screen pen. Based on our findings, this study has the potential to advance the rational design of multifunctional hydrogels, with applications in soft and flexible strain sensors, health monitoring and soft robotics.

THERMO-PHYSICAL PROPERTIES OF LIGHT WEIGHT EPOXY FOAMED BY SILOXANE BLOWING AGENT

The purpose of this study is to investigate the direct effect of using a blowing agent of siloxane (1, 1, 3, 3-tetramethydisiloxane) on the thermo-physical properties of the foamed epoxy. These properties are: density, glass-transition temperature, thermal conductivity and thermal expansion. The work has been conducted experimentally by manufacturing several specimens with different siloxane contents as: 0, 5, 10, 15 and 20 wt%. The properties of the specimens have tested under suitable conditions using different reliable instruments: differential scanning calorimetry, Lee-discs apparatus, and push rod dilatometer. Scanning electron microscope was used as well to analysis the morphological characteristics of the epoxy with respect to the pores generated by the blowing agent. In general, the foamed epoxy has shown different sizes of pores and extra crosslinking which leads to increase the glass-transition temperature of the material. Results show that the addition of 20% siloxane to the neat epoxy (as maximum) leads to: decreasing by 50% in bulk density, increasing by 20% in glass-transition temperature, decreasing by 30% in thermal conductivity, and decreasing by 75% in thermal expansion.

Cross-Linked, Transient Ionic Conductive Elastomer with Extreme Stretchability, Healability, and Degradability for Detecting Human Motions

The fabrication of solvent-free ionic conductive elastomers with high stretchability and degradability is highly desired yet challenging now. Here, solvent-free ionic conductive elastomers were fabricated by the polymerization of acrylic acid (AA)/1-vinylimidazole (IM)-type deep eutectic solvent. An ion pair between AA and IM was formed in the deep eutectic solvent during fabrication. Dynamic bonding including hydrogen bonding and ionic bonding between AA and IM attracted the polymeric chain crosslinking into a liquid-free polymer elastomer without extra cross-linkers. As-prepared conductive elastomers exhibit high transparency (91.4%), ultrahigh stretchability (1464%), fast autonomous self-healing, and degradability. Furthermore, the deep eutectic solvent-based elastomers could be easily attached to human skin and human activities could be detected with high sensitivity. The resulting ionic conductive elastomer with transparency, adhesiveness, self-healing ability, and degradation would meet the Sustainable Development Goals and have potential applications for wearable devices.

3D-Printed, Dual Crosslinked and Sterile Aerogel Scaffolds for Bone Tissue Engineering.

The fabrication of bioactive three-dimensional (3D) hydrogel scaffolds from biocompatible materials with a complex inner structure (mesoporous and macroporous) and highly interconnected porosity is crucial for bone tissue engineering (BTE). 3D-printing technology combined with aerogel processing allows the fabrication of functional nanostructured scaffolds from polysaccharides for BTE with personalized geometry, porosity and composition. However, these aerogels are usually fragile, with fast biodegradation rates in biological aqueous fluids, and they lack the sterility required for clinical practice. In this work, reinforced alginate-hydroxyapatite (HA) aerogel scaffolds for BTE applications were obtained by a dual strategy that combines extrusion-based 3D-printing and supercritical CO2 gel drying with an extra crosslinking step. Gel ageing in CaCl2 solutions and glutaraldehyde (GA) chemical crosslinking of aerogels were performed as intermediate and post-processing reinforcement strategies to achieve highly crosslinked aerogel scaffolds. Nitrogen adsorption–desorption (BET) and SEM analyses were performed to assess the textural parameters of the resulting alginate-HA aerogel scaffolds. The biological evaluation of the aerogel scaffolds was performed regarding cell viability, hemolytic activity and bioactivity for BTE. The impact of scCO2-based post-sterilization treatment on scaffold properties was also assessed. The obtained aerogels were dual porous, bio- and hemocompatible, as well as endowed with high bioactivity that is dependent on the HA content. This work is a step forward towards the optimization of the physicochemical performance of advanced biomaterials and their sterilization.

An injectable mPEG-PDLLA microsphere/PDLLA-PEG-PDLLA hydrogel composite for soft tissue augmentation

Injectable filling material is a simple and efficient method for soft tissues reconstruction and is extremely popular in not only plastic surgery but also cosmetic industry. However, there is a lack of soft tissue fillers with perfect performance on the market currently. Here, we constructed a new microsphere/hydrogel composite and evaluated its potential as a candidate for soft tissue augmentation. mPEG-PDLLA microspheres were prepared by utilizing a SPG membrane emulsifier which endowed microspheres with good sphericity and particle size uniformity. PDLLA-PEG-PDLLA hydrogel which shared the same component with the mPEG-PDLLA copolymer acted as a carrier and fixed the microspheres at the injected sites. The mPEG-PDLLA microsphere/PDLLA-PEG-PDLLA hydrogel composite was flowable in room temperature and transformed into gel after being heated to body temperature. This feature is convenient for subcutaneous filling. In vivo assessment on mice showed good safety profile of the composite. Moreover, the density of collagen fibers increased over 13 weeks. Overall, this biocompatible microsphere/hydrogel composite involves simple component and no extra crosslinking agents, and has the ability to stimulate collagen production, thus, may be a candidate for soft tissue augmentation.

Polyelectrolyte complex nanofiltration membranes by surface deposition of polyethylenimine on polyanion supports

AbstractPolyethylenimine (PEI) is a water‐soluble polymer with higher density of cations and strong adsorbability. In the present work, loose nanofiltration membranes based on PEI were prepared by surface deposition of PEI on hydrolyzed polyacrylonitrile (PANH) supports through a surface crosslink method without using extra crosslinkers. The thinner selective layer (around 50 nm) of polyelectrolyte complex was formed through the crosslinks (ionic and co‐valent) between amine groups in PEI and carboxyl groups in PANH. The PEI/PAN membranes were characterized by SEM, ATR‐IR, and XPS. Nanofiltration of PEGs and salt solutions were performed to evaluate the membrane performance. Loose nanofiltration membranes, with molecular weight cut‐off from 500 to 950 Da, permeances form 7 to 16 L m−2 h−1 bar−1, were obtained by the simple surface crosslink method. The membrane performance can be facile tailored by controlling the deposition parameters, including deposition time and post‐treatments.

Inducing Immunomodulatory Effects on Human Macrophages by Multifunctional NCO-sP(EO-stat-PO)/Gelatin Hydrogel Nanofibers.

Endowing materials and scaffolds with immunomodulatory properties has evolved into a very active field of research. However, combining such effects with multifunctionality regarding cell adhesion and manipulation is still challenging due to the intricate nature of cell-substrate interactions that require fine-tuning of scaffold properties. Here, we reported electrospinning of a well-known biopolymer, gelatin, together with six-arm star-shaped poly(ethylene oxide-stat-propylene oxide) prepolymer with isocyanate end groups (NCO-sP(EO-stat-PO)) as a reactive prepolymer cross-linker. Covalent coupling of two components during and after processing yielded a network of hydrogel fibers that was remarkably stable under aqueous and also proteolytic conditions without the need for extra cross-linking, with a significant increase in stability with increasing NCO-sP(EO-stat-PO) content. When seeded with human macrophages, cells adhered and spread on the fibers and were found highly viable after 7 days of culture across all scaffolds. Furthermore, hybrid fibrous meshes upregulated the expression of a prohealing gene, CD206, while downregulating proinflammatory genes, IL-1β and IL-8. Markedly, NCO-sP(EO-stat-PO)-rich samples induced a significantly reduced release of proinflammatory cytokines, IL-1β, IL-6, and IL-8. Finally, we successfully conjugated IL-4 to NCO-sP(EO-stat-PO) that effectively steered macrophages into a prohealing M2 type, demonstrating additional and robust control over the immunomodulatory feature of the scaffolds.

Tough hydrogels with rapid self-reinforcement.

Most tough hydrogels are reinforced by introducing sacrificial structures that can dissipate input energy. However, because the sacrificial damage cannot rapidly recover, the toughness of these gels drops substantially during consecutive cyclic loadings. We propose a damageless reinforcement strategy for hydrogels using strain-induced crystallization. For slide-ring gels in which polyethylene glycol chains are highly oriented and mutually exposed under large deformation, crystallinity forms and melts with elongation and retraction, resulting both in almost 100% rapid recovery of extension energy and excellent toughness of 6.6 to 22 megajoules per cubic meter, which is one order of magnitude larger than the toughness of covalently cross-linked homogeneous gels of polyethylene glycol.

Tougher when stressed

Hydrogels Hydrogels are typically weak materials because they contain only a small fraction of polymeric material highly swollen with water. Strength can be increased by adding extra cross-linking or interpenetrating networks with some sacrificial bonds to enhance toughness; however, these properties deteriorate upon stretching and may be slow to recover after relaxation. Liu et al. developed polyethylene glycol hydrogels cross-linked with moderate fractions of polymers that form sliding rings. These allow the chain to orient in parallel when stretched, leading to rapid and reversible strain-induced crystallization and thus much tougher hydrogels. Science , aaz6694, this issue p. [1078][1] [1]: /lookup/doi/10.1126/science.aaz6694

Polyethyleneimine‐Mediated Polyamide Composite Membrane with High Perm‐Selectivity for Forward Osmosis

AbstractThin‐film composite (TFC) membranes comprised of a polyamide (PA) selective layer upon a porous substrate dominate the forward osmosis (FO) membrane market. However, further improvement of perm‐selectivity still remains a great challenge. Herein, a polyethyleneimine (PEI) interlayer is intentionally designed prior to interfacial polymerization (IP) to tailor the PA layer, which thus improves the separation performance. The PEI interlayer not only improves the substrate hydrophilicity for adsorbing more diamine monomer and controlling its release rate, but also participates in IP reaction by crosslinking with acyl chloride (TMC). Furthermore, it can decrease the electronegativity of the substrate for decreasing reverse salt diffusion. Consequently, a denser, thinner and smoother PA layer is formed due to the uniform distribution, controllable release of diamine monomer and the extra crosslinking between PEI and TMC. Furthermore, the PA layer becomes more hydrophilic with PEI involvement. As a result, the asprepared TFC membrane exhibits a favorable water flux of 16.1 L m−2 h−1 and an extremely low reverse salt flux (1.25 g m−2 h−1). Meanwhile, it achieves an excellent perm‐selectivity with a ratio of water to salt permeability coefficient of 8.25 bar−1. Moreover, it exhibits an outstanding antifouling capacity. The work sheds light on fabricating high perm‐selective membranes for desalination.

Polyphenol-Assisted Chemical Crosslinking: A New Strategy to Achieve Highly Crosslinked, Antioxidative, and Antibacterial Ultrahigh-Molecular-Weight Polyethylene for Total Joint Replacement.

Highly crosslinked ultrahigh-molecular-weight polyethylene (UHMWPE) bearings are wear-resistant to reduce aseptic loosening but are susceptible to oxidize in vivo/in vitro, as reported in clinical studies. Despite widespread acceptance of antioxidants in preventing oxidation, the crosslinking efficiency of UHMWPE is severely impacted by antioxidants, the use of which was trapped in a trace amount. Herein, we proposed a new strategy of polyphenol-assisted chemical crosslinking to facilitate the formation of a crosslinking network in high-loaded tea polyphenol/UHMWPE blends. Epigallocatechin gallate (EGCG), a representative of tea polyphenol, was mixed with UHMWPE and peroxide. Multiple reactive phenolic hydroxyl groups of tea polyphenol coupled with the nearby free radicals to form extra crosslinking sites. The crosslinking efficiency was remarkably enhanced with increasing tea polyphenol content, even at a concentration of 8 wt %. Given by the hydrogen donation principle, the high-loaded tea polyphenol also enhanced the oxidation stability of the crosslinked UHMWPE. The antioxidative performance was preserved even after tea polyphenol elution. Moreover, superior antibacterial performance was achieved by the in situ tea polyphenol release from the interconnected pathways in the present design. The strategy of polyphenol-assisted chemical crosslinking is applicable for producing highly crosslinked, antioxidative, and antibacterial UHMWPE, which has promising prospects in clinical applications.

Dual-Degradable Biohybrid Microgels by Direct Cross-Linking of Chitosan and Dextran Using Azide-Alkyne Cycloaddition.

In this work, biocompatible and degradable biohybrid microgels based on chitosan and dextran were synthesized for drug delivery applications. Two kinds of bio-based building blocks, alkyne-modified chitosan and azide-modified dextran, were used to fabricate microgels via single-step cross-linking in water-in-oil emulsions. The cross-linking was initiated in the presence of copper(II) without the use of any extra cross-linkers. A series of pH-responsive and degradable microgels were successfully synthesized by varying the degree of cross-links. The microgels were characterized using 1H NMR and FTIR spectroscopy which proved the successful cross-linking of alkyne-modified chitosan and azide-modified dextran by copper(II)-mediated click reaction. The obtained microgels exhibit polyampholyte character and can carry positive or negative charges in aqueous solutions at different pH values. Biodegradability of microgels was shown at pH 9 or in the presence of Dextranase due to the hydrolysis of carbonate esters in the microgels or 1,6-α-glucosidic linkages in dextran structure, respectively. Furthermore, the microgels could encapsulate vancomycin hydrochloride (VM), an antibiotic, with a high loading of approximately 93.67% via electrostatic interactions. The payload could be released in the presence of Dextranase or under an alkaline environment, making the microgels potential candidates for drug delivery, such as colon-specific drug release.

APPLICATION OF DYNAMIC MECHANICAL ANALYSIS FOR UV-CURED COATINGS

The present study is about soya epoxy ester which was made by epoxy resin and fatty acid. Oleochemical polyols were prepared after the soya epoxy ester reacted with various hydroxyl and cellulose based derivatives. These oleochemical polyols were changed to urethanes prepolymers by reacting NCO groups of TDI and IPDI. By utilizing the reaction of NCO end group of urethane with HEMA, these urethanes were transformed in to urethane acrylate oligomer. By mixing the oligomers with various reactive diluents, UV curable coating compositions were derived. The methodology was based on dynamic mechanical analysis. The UV cured samples from cellulose based oleochemical polyols exhibit good mechanical and thermal properties. Their mechanical properties are more dependent on double bonds from unsaturated contribute to curing with extra cross-linking by an oxidative mechanism.

Multifunctional Role of MoS2 in Preparation of Composite Hydrogels: Radical Initiation and Cross-Linking.

This paper describes the multifunctional effect of molybdenum disulfide (MoS2) that enables the rapid and accessible preparation of nanocomposite hydrogels via a bottom-up design. The MoS2 nanoplatelet forms radical species through a redox reaction with persulfate under aqueous conditions while initiating the polymerization of acrylic monomers and providing noncovalent cross-linking points without requiring external stimuli or extra cross-linkers, leading to the formation of hydrogels that are in situ embedded with inorganic flakes. Furthermore, the addition of MoS2 could induce more rigid and elastic networks compared to those in control hydrogels using a typical cross-linker at the same level; for example, 0.08 wt % MoS2 resulted in a composite hydrogel of which the elastic modulus was 2.5 times greater than that from a hydrogel using N,N'-methylenebis(acrylamide) as the showing phase transition during polymerization. The composite hydrogels are self-healable, taking advantage of reversible physical cross-links. Thus, two cut hydrogel strips could be readily rejoined by heating at 70 °C, and the resulting whole strip showed mechanical strength similar to that of the pristine sample before it was cut. This synthetic approach would give way to the modular design of MoS2-containing composite hydrogels.

Mechanical properties, structure, bioactivity and cytotoxicity of bioactive Na-Ca-Si-P-O-(N) glasses

Bioactive glasses are able to bond to bone through formation of carbonated hydroxyapatite in body fluids. However, because of their poor strength their use is restricted to non-load-bearing applications. The effects of nitrogen addition on the physical and mechanical properties and structure of bioactive oxynitride glasses in the system Na-Ca-Si-P-O-N have been studied. Glasses with compositions (mol.%): 29Na2O-13.5CaO-2.5P2O5-(55 -3x)SiO2-xSi3N4 (x is the no. of moles of Si3N4) were synthesised with up to 1.5 at% P and 4.1 at% N. A novel 3-step process was used for addition of P and N and this proved successful in minimising weight losses and producing homogeneous glasses with such high SiO2 contents. The substitution of 4.12 at% N for oxygen results in linear increases in density (1.6%), glass transition temperature (6%), hardness (18%) and Young's modulus (74%). Vickers Indentation Fracture (VIF) resistance (Kifr) was calculated from various relationships depending on the load, indent diagonal, crack lengths and Young's modulus to hardness (E/H) ratio. Firstly, Meyer's index n is calculated from the slope of the logarithmic plot of load versus indent diagonal. Then by comparing the experimental slopes of the logarithmic plots of crack lengths versus load it is concluded that the cracking mode is Radial Median type. The substitution of 4.12 at% N for oxygen results in an increase in Kifr of 40%. These increases in properties are consistent with the incorporation of N into the glass structure in three-fold coordination with silicon which results in extra cross-linking of the glass network. The structure of these bioactive oxynitride glasses was investigated by solid state nuclear magnetic resonance (MAS NMR) of 31P and 29Si. The structure reveals that all the N atoms are bonded to Si atoms with the formation of SiO3N, SiO2N2 and Q4 structural units with extra bridging anions at the expense of Q3 units. The bioactivity of the glasses has been evaluated by soaking them in simulated body fluid (SBF) and results confirm that all these oxynitride glasses are bioactive. Cytotoxicity tests based on different concentrations of these bioactive glass powders in a cell growth environment have also shown that they are not cytotoxic.

Chitin nanocrystal enhanced wet adhesion performance of mussel-inspired citrate-based soft-tissue adhesive

Chitin nanocrystal (ChiNC) with its good biodegradability and biocompatibility as well as rod-like structure characteristic has become one of excellent nanofillers to enhance mechanical properties and bioactivity of biomedical polymers. For further extending its application fields, here, we dispersed ChiNC into a recently synthesized citrate-based tissue adhesive (POEC-d) and explored its effects on the adhesion and cytocompatibility of the adhesive. POEC-d, a mussel-inspired wet adhesive, was prepared by a one-pot melt polycondensation of 1, 8-octanediol, poly(ethylene oxide) (PEO), citric acid (CA) and dopamine (DA). The good water-solubility of POEC-d allowed facilely blending ChiNC and POEC-d to ultimately acquire POEC-d/ChiNC nanocomposite adhesives. The results showed the ChiNCs were finely dispersed in the POEC-d matrix and endowed the adhesive with extra crosslinks to enhance the bulk cohesion property. Synchronously, the lap-shear adhesion strengths measured by bonding wet porcine skins considerably improved with increasing the ChiNC content. In addition, the POEC-d/ChiNC nanocomposite adhesives exhibited lower swelling ratio as compared to the POEC-d adhesive as well as good cytocompatibility, revealing their superior applicability in soft-tissue adhesion.