Click Cross-Linking-Improved Waterborne Polymers for Environment-Friendly Coatings and Adhesives

Washable Superhydrophobic Cotton Fabric with Photothermal Self-Healing Performance Based on Nanocrystal-MXene

Superhydrophobic fabrics suffer from being commonly penetrated by moisture after laundering, seriously deteriorating their water repellency after air drying. Numerous researchers have successfully recovered superhydrophobicity by drying in fluid ovens; however, high energy consumption and equipment dependence limit practical applications. Herein, the superhydrophobic photothermal self-healing cotton fabric (SPS cotton fabric) was fabricated by depositing a composite layer of cellulose nanocrystal-MXene (C-MXene) and polyacrylate (PA) coatings on the cotton cloth. Superior photothermal conversion of the SPS cotton fabric performance enables its 10.5-56.8 °C greater temperature than that of the pure hydrophobic cotton fabric under different simulated solar light intensities. After washing, the SPS cotton fabric can spontaneously restore superhydrophobicity with ≈100% efficiency by 30 mW·cm-2 solar light irradiation; in contrast, the single superhydrophobic fabrics recover only ≈71.2%. Even after 10 washing cycles, the recovery efficiency of the SPS cotton fabric only decreases by 0.1%, exhibiting excellent laundering durability. The SPS cotton fabric can retain ultralong time antifrosting (2760 s) and antifreezing (4080 s) capacities due to sustainable water repellency. Remarkably, the excellent self-healing capability of the SPS cotton fabric is attributed to the fact that the coiled nonpolar alkane chains can be restored to a straight state by autothermal drive, confirmed through element analyses and molecular dynamics simulations.

Click Chemistry as an Efficient Toolbox for Coupling Sterically Hindered Molecular Systems to Obtain Advanced Materials for Nanomedicine

Since its conceptualization, click chemistry in all its variants has proven to be a superior synthesis protocol, compared to conventional methods, for forming new covalent bonds under mild conditions, orthogonally, and with high yields. If a term like reactive resilience could be established, click reactions would be good examples, as they perform better under increasingly challenging conditions. Particularly, highly hindered couplings that perform poorly with conventional chemistry protocols-such as those used to conjugate biomacromolecules (e.g., proteins and aptamers) or multiple drugs onto macromolecular platforms-can be more easily achieved using click chemistry principles, while also promoting high stereoselectivity in the products. In this review, three molecular platforms relevant in the field of nanomedicine are considered: polymers/copolymers, cyclodextrins, and fullerenes, whose functionalization poses a challenge due to steric hindrance, either from the intrinsic bulk behavior (as in polymers) or from the proximity of confined reactive sites, as seen in cyclodextrins and fullerenes. Their functionalization with biologically active groups (drugs or biomolecules), primarily through copper-catalyzed azide-alkyne cycloaddition (CuAAC), strain-promoted azide-alkyne cycloaddition (SPAAC), inverse electron-demand Diels-Alder (IEDDA) and thiol-ene click reactions, has led to the development of increasingly sophisticated systems with enhanced specificity, multifunctionality, bioavailability, delayed clearance, multi-targeting, selective cytotoxicity, and tracking capabilities-all essential in the field of nanomedicine.

Waterborne Liquid-like Coatings with High Transparency, Superior Scratch Resistance, and Antismudge Properties

The aqueous formulation of antismudge coatings is a crucial step for environmental protection and pollution reduction. However, the inferior mechanical durability of waterborne antismudge coatings poses challenges for their practical application. Herein, we developed a fully waterborne antismudge coating with excellent scratch resistance by preparing hyperbranched amine-rich polysiloxane (HySPx) for antismudge ability and epoxy-rich zirconium-based aqueous solution (ZAS) for mechanical performance. The former is obtained by combining SPx, polydimethylsiloxane modified by 3-isocyanatopropyltriethoxysilane (IPTS), with 3-aminopropyltriethoxysilane (KH550), and the latter is synthesized using zirconium propoxide solution (TPOZ) with 3-glycidyloxypropyltrimethoxysilane (KH560). This report investigates the effects of the chain length and content of SPx on the performance of the coating. The results indicate that the coating exhibits optimal comprehensive performance when the molecular weight of polydimethylsiloxane is 4.5 kDa, and the mass fraction of SPx in HySPx is 1.5%. The coating possesses high transparency similar to glass, good adhesion (≈3 MPa) to various substrates, high hardness (8H), flexibility (2.5 mm bending radius), and exceptional antismudge property. More importantly, the coating can still maintain excellent antismudge property even after enduring 400 cycles of abrasion with steel wool. Furthermore, the rapid enrichment of polydimethylsiloxane on the coating surface endows the coating with excellent lubrication ability, allowing most common liquid stains to slide off the coating surface. Moreover, the rewritability of the coating remains stable even after writing traces that have persisted on its surface for several weeks. This coating is anticipated to be utilized for protecting foldable electronic screens, vehicles, and other fields.

Polymerized and Colloidal Ionic Liquids─Syntheses and Applications

The breadth and importance of polymerized ionic liquids (PILs) are steadily expanding, and this review updates advances and trends in syntheses, properties, and applications over the past five to six years. We begin with an historical overview of the genesis and growth of the PIL field as a subset of materials science. The genesis of ionic liquids (ILs) over nano to meso length-scales exhibiting 0D, 1D, 2D, and 3D topologies defines colloidal ionic liquids, CILs, which compose a subclass of PILs and provide a synthetic bridge between IL monomers (ILMs) and micro to macro-scale PIL materials. The second focus of this review addresses design and syntheses of ILMs and their polymerization reactions to yield PILs and PIL-based materials. A burgeoning diversity of ILMs reflects increasing use of nonimidazolium nuclei and an expanding use of step-growth chemistries in synthesizing PIL materials. Radical chain polymerization remains a primary method of making PILs and reflects an increasing use of controlled polymerization methods. Step-growth chemistries used in creating some CILs utilize extensive cross-linking. This cross-linking is enabled by incorporating reactive functionalities in CILs and PILs, and some of these CILs and PILs may be viewed as exotic cross-linking agents. The third part of this update focuses upon some advances in key properties, including molecular weight, thermal properties, rheology, ion transport, self-healing, and stimuli-responsiveness. Glass transitions, critical solution temperatures, and liquidity are key thermal properties that tie to PIL rheology and viscoelasticity. These properties in turn modulate mechanical properties and ion transport, which are foundational in increasing applications of PILs. Cross-linking in gelation and ionogels and reversible step-growth chemistries are essential for self-healing PILs. Stimuli-responsiveness distinguishes PILs from many other classes of polymers, and it emphasizes the importance of segmentally controlling and tuning solvation in CILs and PILs. The fourth part of this review addresses development of applications, and the diverse scope of such applications supports the increasing importance of PILs in materials science. Adhesion applications are supported by ionogel properties, especially cross-linking and solvation tunable interactions with adjacent phases. Antimicrobial and antifouling applications are consequences of the cationic nature of PILs. Similarly, emulsion and dispersion applications rely on tunable solvation of functional groups and on how such groups interact with continuous phases and substrates. Catalysis is another significant application, and this is an historical tie between ILs and PILs. This component also provides a connection to diverse and porous carbon phases templated by PILs that are catalysts or serve as supports for catalysts. Devices, including sensors and actuators, also rely on solvation tuning and stimuli-responsiveness that include photo and electrochemical stimuli. We conclude our view of applications with 3D printing. The largest components of these applications are energy related and include developments for supercapacitors, batteries, fuel cells, and solar cells. We conclude with our vision of how PIL development will evolve over the next decade.

Effect of diets supplemented with coated plant essential oil on the growth performance, immunity, antioxidant activity, and fecal microbiota of weaned piglets

Introduction

This trial was conducted to compare the effect of diets supplemented with plant essential oil (PEO) and coated plant essential oil (CEO) on growth performance, immunity, antioxidant activity, and fecal microbiota of weaned piglets.

Methods

A total of 360 21-day-old weaned piglets were randomly allocated into three groups, namely, CON, PEO, and CEO (basal diets supplemented with 0, 500 mg/kg PEO, and 500 mg/kg CEO, respectively) for a 4-week feeding trial.

Results and discussion

The results showed that dietary supplementation with CEO improved the average final weight and average daily gain, decreased the diarrhea rate, increased antioxidant enzyme activities, enhanced immunoglobulin concentrations, and decreased concentrations of pro-inflammatory cytokines in the serum of weaned piglets (p < 0.05). In addition, CEO addition increased the fecal concentrations of propionic acid and isovaleric acid of piglets (p < 0.05). Spearman correlation analysis showed that fecal microorganisms at the genus level were closely correlated with the volatile fatty acid concentrations. The present study indicated that PEO and CEO could improve growth performance, enhance immunity, and increase antioxidant capacity by modulating the microbial flora in weaned piglets. Moreover, CEO addition seemed to offer more positive results than of PEO addition.

Modification of nanocellulose via atom transfer radical polymerization and its reinforcing effect in waterborne UV-curable resin

Cellulose nanocrystals (CNCs) are green reinforcing materials, and their potential has been evaluated in the preparation of waterborne UV-curable resin composites with high-performance. Herein, we present a novel and scalable approach for preparing surface-modified CNCs with acrylic-based polymers to strengthen the compatibility and interaction between CNCs and UV-curable resins. Using tert-butyl acrylate as the monomer, the nanocellulose grafted copolymer CNC-g-PtBA was successfully synthesized via atom transfer radical polymerization (ATRP) in the presence of a macromolecular initiator. Then, the CNC-g-PtBA is blended into the acrylic resin as a nanofiller to prepare the UV-curable nanocomposite. The results indicated that the contact angle of the CNCs increased from 38.7° to approximately 74.8°, and their thermal stability was significantly improved after graft modification. This contributed to the effective alleviation of the agglomeration phenomenon of nanocomposites due to the high hydrophilicity of pure CNCs. Notably, not only was the UV curing efficiency of the nanocomposites greatly increased but the mechanical properties were also further enhanced. Specifically, with the addition of 0.5 wt% CNC-g-PtBA, the curing time of the nanocomposite was shortened from >30 mins down to approximately 6 mins, and the bending strength was increased from 10 MPa for the original resin and 5 MPa for the addition of pure CNCs to 14.3 MPa, and the bending modulus was also greatly increased (up to approximately 730 MPa). Compared to pure CNCs, they are compatible with the resin, exhibiting high mechanical strength and flexibility, and have virtually no effect on the light transmission of the nanocomposites. Additionally, dielectric analysis (DEA) was used to monitor the dielectric constant and conductivity of the UV-curable nanocomposites in real time to further characterize their curing kinetics. The permittivity of these nanocomposites increased by 125 % compared to pristine resin, which shows potential for applications in high dielectric composites or for improving electrical conductivity. This work provides a feasible method for preparing UV-curable nanocomposites with high curing efficiency and permittivity, realizing a wider application of this high-performance nanocomposite.

Castor oil-based waterborne polyurethane/tunicate cellulose nanocrystals nanocomposites for wearable strain sensors

In this study, tunicate cellulose nanocrystals (TCNCs) were introduced into castor oil-based waterborne polyurethane (WPU) to prepare bio-based nanocomposites through a simple solution blending method. The effect of TCNCs content on the particle size and stability of the composite dispersions, as well as the thermophysical and mechanical properties of the composite films were studied and discussed. The unique structure and properties of TCNCs, such as high crystallinity, large aspect ratio and high modulus, not only greatly improved the storage stability of WPU, but also showed significant reinforcing/toughening effects and excellent compatibility to WPU. By drip-coating silver nanowires (AgNWs) on the surface of the composite films, the flexible strain sensors were fabricated, which showed excellent sensitivity in monitoring human movement.

Multifunctional Waterborne Polyurethane Microreactor-Based Approach to Fluorocarbon Composite Latex Coatings with Double Self-Healing and Excellent Synergistic Performances

In this article, chlorotrifluoroethylene (CTFE)-based fluorocarbon composite latexes and their coatings are successfully fabricated by an environmentally friendly preparation method based on a new multifunctional waterborne polyurethane (MFWPU) dispersion. It is worth noting that the MFWPU acts as the sole system stabilizer as well as microreactor and simultaneously endows the composite coating with excellent double self-healing performance and adhesion. Moreover, the introduction of a dynamic disulfide bond in the polyurethane dispersion entrusts the coating with excellent scratch self-healing performance. Simultaneously, carbon-carbon double bonds in the polyurethane dispersion increase the compatibility between the core polymer and shell polymer. The fluorine-containing chain segments can be distributed in the coating evenly during the self-assembly film-forming process of composite particles so that the original element composition of the worn coating surface can restore the original element composition after heating, and the coating presents a regeneration ability, which further and verifies the usefulness of the double self-healing model of the coating. Afterward, efficient recovery and durability, which are two contradictory properties of scratch self-healing polymers, are optimized to obtain a composite coating with excellent comprehensive performance. The research results regarding the composite system may provide a valuable reference for the structural design and application of waterborne fluorocarbon functional coatings in the future.

An eco-friendly wood adhesive based on waterborne polyurethane grafted with gelatin derived from chromium shavings waste

An environmentally friendly wood adhesive developed from waterborne polyurethane (WPU) grafted gelatin (G) was investigated in this research. First, the G was extracted from chromium shavings waste, and then mixed with a prepolymer emulsion of WPU to synthesis the graft copolymer (WPUG) via a solvent-free emulsion copolymerization. The synthesized copolymer was characterized using the mechanical properties test, TGA, FT-IR, and other analysis technology. The results indicated that the WPUG had a good overall performance. Specifically, the contact angle reached 111.5°, the tensile strength reached 32.91 MPa, the temperature of the maximum weight loss was greater than 350 °C. The WPUG adhesive had excellent bonding power and mechanical properties; the dry bonding strength reached 4.21 MPa when the ratio between free amino groups of the G and isocyanate-groups of the WPU (the R value) was 1.5. This preparation of the graft copolymer not only satisfies the need of environment-friendly wood adhesives, but it also effectively improves the recyclability of chromium shavings waste.

Demonstration of temperature-sensitive paints with rigorously controlled thickness applied to variously shaped metal substrates with a highly stable connection based on a demulsification-induced fast solidification strategy

Temperature-sensitive paints with rigorously controlled thickness are in situ fabricated on metal surfaces based on the demulsification-induced fast solidification method.

Active bayerite underpinned Ag2O/Ag: An efficient antibacterial nanohybrid combating microbial contamination

Active surfaces with bactericidal properties are of paramount importance in health care sector as a judicious approach to confront prevalent challenges presented by disastrous pathogenic infections and antibiotic-resistant microbes. Herein, we present Bayerite underpinned Ag2O/Ag (ALD), a nanohybrid with excellent antibacterial and antibiofilm functionalities against tested standard strains and clinical isolates. The multicomponent system coexists and complement each other with respect to phase and functionalities, demonstrated by XRD, XPS and TEM analyses. In situ reduction of Ag+ ions to Ag0 over Bayerite as a stable bound phase is favoured by pH of the reaction, yielding 60-80% bound Ag protruding outwards facilitating active surface for interaction with microbes. ALD has a minimum inhibitory concentration (MIC) of 0.068 mg/mL against clinical isolates: Pseudomonas aeruginosa RRLP1, RRLP2, Acinetobactor baumannii C78 and C80. Disc diffusion assay demonstrated excellent antibacterial activity against standard strains (positive control: standard antibiotic disc, Amikacin). ALD incorporated PMMA films (5 and 10 wt%(PALD-5 and PALD-10) exhibited significant contact killing (99.9%) of clinical isolates in drop-test besides strong antibacterial activity (disc diffusion assay) comparable to that of ALD. ALD exemplified a dose (0.034 mg/mL and 0.017 mg/mL) dependent biofilm inhibition (p < 0.001) and significant eradication of pre-formed biofilms (p < 0.001) by clinical isolates. PALD 5 and PALD 10 significantly declined the number of viable biofilm associated bacteria (99.9%) compared to control. Both ALD and PALD samples are proposed as green antibacterial materials with antibiofilm properties. Results also present ample opportunity to explore PALD as antibacterial and/or antibiofilm coating formulations.

Core/shell colloidal nanoparticles based multifunctional and robust photonic paper via drop-casting self-assembly for reversible mechanochromic and writing

Photonic crystals film that possesses periodic dielectric structure have shown great prospect in developing environmentally friendly paper alternatives due to the unique properties of dye free and non-photobleaching, but their practical application is limited by the weak interaction between colloidal particles. Although some progress has been obtained, it is still a challenge to develop photonic paper with the desired mechanical and optical properties. Herein, multifunctional hard core/soft shell nanoparticles with controlled size are fabricated by semi-continuous seed emulsion polymerization method. Compared with convention colloidal particles, these core/shell nanoparticles can facile self-assemble into large-scale dense ordered structure film via dried at room temperature due to the relatively low glass transition temperature (Tg) of the shell layers. The facile fabrication route enables the continuous high-through put production of the photonic papers. The as-formed papers not only possess the capacity to solvent (water/ethanol) rewritable and multicolor painting, but also can rapidly reversible mechanochromic. Moreover, due to the good compatibility of core/shell interface, these photonic films possess excellent mechanical properties, demonstrating that this multifunctional film makes the fabrication of novel robust rewritable papers possible and enables visual monitoring of deformation degree.

Environmental benefits of soy-based bio-adhesives as an alternative to formaldehyde-based options

The restrictions imposed on the use of formaldehyde in wood panel adhesives have been the driving force behind the development of formaldehyde-free resins for the manufacture of wood products. Considering as a boundary condition the idea that the use of fossil-based raw materials should be replaced by biological options, there is growing interest in the environmental assessment of different alternatives for soy-based adhesives, as possible options to replace commonly used synthetic resins. This report includes the environmental profiles of soy-based adhesives taking into account the life cycle assessment (LCA) methodology. In addition, in order to increase their potential to replace synthetic resins, a sensitivity analysis of the main contributors to environmental damage was performed, thus giving an open guide for further research and improvement. This study aims to provide innovative alternatives and new trends in the field of environmentally friendly bio-adhesives for the wood panel industry.

Highly Stable Waterborne Luminescent Inks Based on MAPbBr3@PbBr(OH) Nanocrystals for LEDs and Anticounterfeit Applications

Waterborne polymers are advantageous in terms of cost, convenience, sustainability, and environmental friendliness. As lead halide perovskite (LHP) nanocrystals suffer from fast degradation in the presence of water, it is challenging to encapsulate LHP nanocrystals in waterborne polymers. In this work, luminescent MAPbBr₃@PbBr(OH) nanocrystals were synthesized via the aqueous grinding process in the presence of 2-methyl-imidazole (2-MIM) and oleylamime (OAm). 2-MIM triggers the formation of the PbBr(OH) matrix, and OAm acts as a size-control ligand to control the size of MAPbBr₃@PbBrOH particles in the nanoscale range. Highly stable waterborne luminescent inks were successfully prepared by blending MAPbBr₃@PbBr(OH) nanocrystals with waterborne polymers, including poly(vinylpyrrolidone), poly(vinyl acetate), and acrylate resins. Owning to the dual protection of the polymer matrix and PbBr(OH) to LHP quantum dots (QDs), the luminescent films exhibit excellent stability to the environment under thermal and light irradiation. The ink can be used as a phosphor to fabricate down-converting green and white light-emitting diodes (LEDs). Waterborne anticounterfeiting inks suitable for screen printing were prepared via formula tuning for the anticounterfeit purpose. The anticounterfeiting luminescent patterns can be screen printed on paper, cloth, and poly(ethylene terephthalate) (PET), with encryption and decryption of information being accurately and conveniently realized by switching UV irradiation.

Overview of Silica-Polymer Nanostructures for Waterborne High-Performance Coatings

Combining organic and inorganic components at a nanoscale is an effective way to obtain high performance coating materials with excellent chemical and physical properties. This review focuses on recent approaches to prepare hybrid nanostructured waterborne coating materials combining the mechanical properties and versatility of silica as the inorganic filler, with the flexural properties and ease of processing of the polymer matrix. We cover silica-polymer coupling agents used to link the organic and inorganic components, the formation of hybrid films from these silica-polymer nanostructures, and their different applications. These hybrid nanostructures can be used to prepare high performance functional coatings with different properties from optical transparency, to resistance to temperature, hydrophobicity, anti-corrosion, resistance to scratch, and antimicrobial activity.

Dialdehyde modified cellulose nanofibers enhanced the physical properties of decorative paper impregnated by aldehyde-free adhesive

Impregnated decorative paper was an important wood-based panel finishing material. However, traditional impregnated decorative paper was impregnated with melamine-formaldehyde resin, which will release formaldehyde and harm the human health. To solve this problem, small molecule polyacrylate-polyethylene glycol (PEG) adhesive was used to achieve the non-formaldehyde addition of the impregnation system. The dialdehyde modified CNF (D-CNF), modified by sodium periodate (NaIO₄), and triethylenediamine were introduced to enhance the surface properties of the impregnated decorative paper. The results showed that the incorporation of D-CNF and triethylenediamine imparted excellent physical strength and surface properties to impregnated decorative paper. When the dosage of 0.3 wt% D-CNF and 3 mL/100 g triethylenediamine in the compound emulsion, the hardness, abrasion resistant value and surface bonding strength of impregnated decorative paper adhered fiberboard reached 3H, 330 r of damage and 1.13 MPa, respectively. Thus, it could be effectively used for making high-performance formaldehyde-free impregnated decorative paper.

High-performance water-borne fluorescent acrylic-based adhesive: synthesis and application

Water-borne adhesives have immense importance in cellulose-based materials, where their durability, handling, and strength remain to be a major concern. The present work demonstrates the development of three water-borne adhesives, namely, poly(1-vinyl-2-pyrrolidone-co-acrylic acid), poly(acrylonitrile-co-acrylic acid), and poly(1-vinyl-2-pyrrolidone-co-acrylonitrile-co-acrylic acid) applicable for cellulose-based materials. These acrylic-acid based adhesives were characterized by Fourier-transform infra-red spectroscopy, thermogravimetric analysis, X-ray diffraction, gel permeation chromatography, and universal testing machine. The synthesized polymer adhesives can be stored in the powder form for a longer period, thus utilizing less space. In order to use as adhesives, suitable formulations can be prepared in water. The adhesives show thermal stability up to 300 °C. Our studies show that poly(1-vinyl-2-pyrrolidone-co-acrylonitrile-co-acrylic acid) showed higher lap shear strength (ASTM D-906) than commercially available adhesives. In addition, these adhesives, being fluorescent in nature, can be detected under UV light and thus are applicable for the detection of fractured joints of any specimen. This property also helps in anti-counterfeiting applications, thus adding further to their utility.

Synthesis and application of a water-borne fluorescent acrylic adhesive, which can be stored as a powder for long-term use.

Mechanism and control of "coffee-ring erosion" phenomena in structurally colored ionomer films

Ionomer polyesters have polymer backbones functionalized with charged groups that make them water-dispersible. Despite the widespread use of ionomer polymers in environmentally friendly coatings without volatile organic solvents, the fundamental understanding of their film formation properties is still limited. In the study, we deposited polyester nanofilms of brilliant structural colors and correlated the macroscale optical properties to the microscale thickness of the thin films. We found that sessile water droplets deposited on these films drive the formation of a rich variety of structures by an evaporation-induced effect of "coffee-ring erosion". The ionomers spontaneously get partially re-dispersed in the form of nanoparticles in the sessile droplets and driven by convective evaporation flows, become redistributed in multiple colorful ring patterns. By using the structural colors as means to follow the polymer redistribution, we characterized further the coffee-ring patterns and found that the generated patterns are dictated by polymer composition but are mostly independent on molecular weight. As expected by colloidal theory, this phenomenon was suppressed in presence of electrolytes. Furthermore, we show that the integrity of these thin polyester films can be significantly improved by thermal densification without any further chemical curing.

Gas hydrates in sustainable chemistry

This review includes the current state of the art understanding and advances in technical developments about various fields of gas hydrates, which are combined with expert perspectives and analyses.

Development of osteopromotive poly (octamethylene citrate glycerophosphate) for enhanced bone regeneration

The design and development of bioactive materials that are inherently conducive for osteointegration and bone regeneration with tunable mechanical properties and degradation remains a challenge. Herein, we report the development of a new class of citrate-based materials with glycerophosphate salts, β-glycerophosphate disodium (β-GP-Na) and glycerophosphate calcium (GP-Ca), incorporated through a simple and convenient one-pot condensation reaction, which might address the above challenge in the search of suitable orthopedic biomaterials. Tensile strength of the resultant poly (octamethylene citrate glycerophosphate), POC-βGP-Na and POC-GP-Ca, was as high as 28.2 ± 2.44  MPa and 22.76 ± 1.06  MPa, respectively. The initial modulus ranged from 5.28 ± 0.56  MPa to 256.44 ± 22.88  MPa. The mechanical properties and degradation rate of POC-GP could be controlled by varying the type of salts, and the feeding ratio of salts introduced. Particularly, POC-GP-Ca demonstrated better cytocompatibility and the corresponding composite POC-GP-Ca/hydroxyapatite (HA) also elicited improved osteogenic differentiation of human mesenchymal stem cells (hMSCs) in vitro, as compared to POC-βGP-Na/HA and POC/HA. The superior in-vivo performance of POC-GP-Ca/HA microparticle scaffolds in promoting bone regeneration over POC-βGP-Na/HA and POC/HA was further confirmed in a rabbit femoral condyle defect model. Taken together, the tunability of mechanical properties and degradation rates, together with the osteopromotive nature of POC-GP polymers make these materials, especially POC-GP-Ca well suited for bone tissue engineering applications. STATEMENT OF SIGNIFICANCE: The design and development of bioactive materials that are inherently conducive for osteointegration and bone regeneration with tunable mechanical properties and degradation remains a challenge. Herein, we report the development of a new class of citrate-based materials with glycerophosphate salts, β-glycerophosphate disodium (β-GPNa) and glycerophosphate calcium (GPCa), incorporated through a simple and convenient one-pot condensation reaction. The resultant POC-GP polymers showed significantly improved mechanical property and tunable degradation rate. Within the formulation investigated, POC-GPCa/HA composite further demonstrated better bioactivity in favoring osteogenic differentiation of hMSCs in vitro and promoted bone regeneration in rabbit femoral condyle defects. The development of POC-GP expands the repertoire of the well-recognized citrate-based biomaterials to meet the ever-increasing needs for functional biomaterials in tissue engineering and other biomedical applications.

Waterborne Polyurethanes as a New and Promising Class of Kinetic Inhibitors for Methane Hydrate Formation

A facile, new and promising technique based on waterborne polymers for designing and synthesizing kinetic hydrate inhibitors (KHIs) has been proposed to prevent methane hydrate formation. This topic is challenging subject in flow assurance problems in gas and oilfields. Proposed technique helps to get KHIs with required number and distance of hydrophilic and hydrophobic groups in molecule and good solubility in water. The performance of these new KHIs was investigated by high pressure micro-differential scanning calorimeter (HP-μDSC) and high-pressure autoclave cell. The results demonstrated the high performance of these inhibitors in delay the induction time (10–20 times) and reduce the hydrate growth rate (3 times). Also they did not increase hydrate dissociation temperature in comparison with pure water and show thermodynamic inhibition as well. Inhibition effect of synthesized polymers is improved with the increase of concentration significantly. Since this is the first report of the use of waterborne polymers as kinetic hydrate inhibitor, we expect that KHIs based on waterborne-based polymers can be a prospective option for preventing methane hydrate formation.

Preparation and Characterization of Poly-1,2,3-triazole with Chiral 2(5H)-Furanone Moiety as Potential Optical Brightening Agents

A series of novel heterocyclic polymers with fluorescent brightening properties are synthesized via Click polymerization. Fast synthesis of poly-1,2,3-triazoles (M n ≥ 9.31 kDa) is described herein, with a high yield of up to 95%. The Click polymerization approach has a number of advantages, including facile operation and outstanding isolation yield. The resultant polymers have a high thermal stability, excellent UV resistance, as well as acid and light fastness. On embedding with optical brightening agents, the polymers display strong fluorescent brightening properties in the tetrahydrofuran solution. Moreover, these products have a strong solution emission intensity and extraordinary photostability under UV light.

Superhydrophobic/Superoleophilic and Reinforced Ethyl Cellulose Sponges for Oil/Water Separation: Synergistic Strategies of Cross-linking, Carbon Nanotube Composite, and Nanosilica Modification

Superhydrophobic/superoleophilic and reinforced ethyl cellulose (SEC) sponges were prepared by cross-linking EC with epichlorohydrin (ECH) and complexing with silanized carbon nanotubes (Si-CNTs) followed by coating nanosilica on the surface of porous sponges and subsequent modification with hexadecyltrimethoxysilane (HDTMS). These synergistic strategies endowed the SEC sponges with the superhydrophobic/superoleophilic properties (θ_water = 158.2°, θ_oil = 0°, sliding angle = 3°) and outstanding mechanical properties (could bear the pressure of 28.6 kPa without damage). The unique micronanostructures and properties of the porous sponges were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and water contact angle measurements. The as prepared SEC sponges with high mechanical strength were able to collect a wide range of oils and organic solvents with absorption capacity up to 64 times of their own weight. Furthermore, the absorption capacity of the sponges decreased slightly to 86.4% of its initial value after 50 separation cycles, suggesting their excellent recyclable performance. The high efficiency and endurability of the sponges during oil/water separation made them ideal absorbent in oil spillage cleanup.

A mini review of the synthesis of poly-1,2,3-triazole-based functional materials

Most recent advances of the synthesis of poly-1,2,3-triazole-based functional materials.

Development of contact-killing non-leaching antimicrobial guanidyl-functionalized polymers via click chemistry

A new contact-killing and non-leaching antimicrobial polymer was prepared by a robust, efficient and orthogonal click-chemistry.

Click chemistry improved wet adhesion strength of mussel-inspired citrate-based antimicrobial bioadhesives

For the first time, a convenient copper-catalyzed azide-alkyne cycloaddition (CuAAC, click chemistry) was successfully introduced into injectable citrate-based mussel-inspired bioadhesives (iCMBAs, iCs) to improve both cohesive and wet adhesive strengths and elongate the degradation time, providing numerous advantages in surgical applications. The major challenge in developing such adhesives was the mutual inhibition effect between the oxidant used for crosslinking catechol groups and the Cu(II) reductant used for CuAAC, which was successfully minimized by adding a biocompatible buffering agent typically used in cell culture, 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES), as a copper chelating agent. Among the investigated formulations, the highest adhesion strength achieved (223.11 ± 15.94 kPa) was around 13 times higher than that of a commercially available fibrin glue (15.4 ± 2.8 kPa). In addition, dual-crosslinked (i.e. click crosslinking and mussel-inspired crosslinking) iCMBAs still preserved considerable antibacterial and antifungal capabilities that are beneficial for the bioadhesives used as hemostatic adhesives or sealants for wound management.