Acrylate Functionality Research Articles

Formulation of a Ceramic Ink for 3D Inkjet Printing.

Due to its multi-material capabilities, 3D inkjet printing allows for the fabrication of components with functional elements which may significantly reduce the production steps. The potential to print electronics requires jettable polymer-ceramic composites for thermal management. In this study, a respective material was formulated by functionalizing submicron alumina particles by 3-(trimethoxysilyl)propylmethacrylate (MPS) and suspending them in a mixture of the oligourethane Genomer 4247 with two acrylate functionalities and a volatile solvent. Ink jetting tests were performed, as well as thermal conductance and mechanical property measurements. The material met the strict requirements of the printing technology, showing viscosities of around 16 mPa·s as a liquid. After solidification, it exhibited a ceramic content of 50 vol%, with a thermal conductance of 1 W/(m·K). The resulting values reflect the physical possibilities within the frame of the allowed tolerances set by the production method.

Optimizing the performance of sustainable nail gel compositions using a mixture experimental design methodology

This study presents the development of two major classes of oligomers extensively used in nail gel formulations – urethane acrylates and polyester acrylates – using sustainable routes. To this end, a series of non-isocyanate acrylic functional polyurethane oligomers (NIPU-ACs) were synthesized by the reaction of cyclic carbonates with a stoichiometric excess of amine, followed by reacting the amine-end groups with methacrylic anhydride (MAAH) to introduce the acrylate functionalities. Moreover, a series of different bio-renewable based polyester oligomers (BR-PS) were synthesized from ring-opening esterification of epoxidized soybean oil (ESO) with various mono/di acids such as rosin, benzoic acid, and itaconic acid.Next, the mixture experimental design methodology was used to formulate two categories of sustainable nail gels based on NIPU-ACs and BR-PS oligomers. The formulations were then evaluated for a set of screening tests, and Design-Expert® software was used to determine the most suitable correlation between the variable parameters and responses. In each category, the optimized formulation was selected based on the desired performance criteria and evaluated for complementary tests. Finally, three-layer nail gels systems were also developed and tested for durability and removability.The nail gel systems developed in this study not only have eco-friendly composition but meet critical requirements such as fast-curing (1−2 min), easy removability (in 5 min), high gloss (> 85 T 60°), and high durability (> 10,000 wet scrub cycles, acetone double rubs > 100, and abrasion resistance of < 20 mg after 500 cycles). The combination of these attributes makes these nail gels attractive alternatives to the incumbent products for commercial markets.

Polymer architecture as key to unprecedented high-resolution 3D-printing performance: The case of biodegradable hexa-functional telechelic urethane-based poly-ε-caprolactone

Two-photon polymerization (2PP) is a high-resolution 3D-printing technology with a very rapidly expanding field of applications, including tissue engineering (TE). In this field, 2PP offers unprecedented possibilities for systematic studies of both cell–cell and cell–material interactions in 3D. For TE applications, the reliable production of biodegradable micro-scaffolds in porous, complex architectures is essential. However, the number of biodegradable materials that support the required level of spatial resolution is very limited, being a major bottleneck for the use of 2PP in the TE field.Herein, we introduce a hexa-functional urethane-based biodegradable precursor that overcomes the limitations associated with the high-resolution printing of current biodegradable precursors. The precursor is a telechelic urethane-based poly-ε-caprolactone (PCL) possessing three acrylate functionalities at each polymer end group which enables the reliable production of complex architectures owing to its superior physical properties as compared to the traditional di-acrylate terminated analogs. The newly developed hexa-functional telechelic urethane-based PCL reveals enhanced crosslinking kinetics and one order of magnitude higher Young’s modulus compared to the di-functional precursor (57.8 versus 6.3 MPa), providing an efficient and solvent-free 2PP processing at fast scanning speeds of up to 100 mm s−1 with unprecedented feature resolutions (143 ± 18 nm at 100 mm s−1 scanning speed). The crosslinked hexa-functional polymer combines strength and flexibility owing to the segregation between its hard polyacrylate and soft PCL segments, which makes it suitable for biological systems in contrast to the highly crosslinked and rigid structures typically manufactured by 2PP. Furthermore, it revealed lower degradation rate compared to its di-functional analog, which can be considered as an advantage in terms of biocompatibility due to the slower formation of acidic degradation products. Extracts of the developed polymers did not show a cytotoxic effect on the L929 fibroblasts as confirmed via ISO 10993-5 standard protocol. The presented precursor design constitutes a simple and effective approach that can be easily translated towards other biodegradable polymers for the manufacturing of biodegradable constructs with nano-scale precision, offering for the first time to use the true capabilities of 2PP for TE applications with the use of synthetic biodegradable polymers.

Acrylic Functionalization of Cellulose Nanocrystals with 2-Isocyanatoethyl Methacrylate and Formation of Composites with Poly(methyl methacrylate).

Cellulose nanocrystals (CNCs) derived from renewable plant-based materials exhibit strong potential for improving properties of polymers by their dispersal in the polymer matrix as a composite phase. However, the hydrophilicity and low thermal stability of CNCs lead to compromised particle dispersibility in common polymers and limit the processing conditions of polymer–CNC composites, respectively. One route that has been explored is the modification of CNCs to alter surface chemistry. Acrylic materials are used in a broad class of polymers and copolymers with wide commercial applications. Yet, the available methods for adding groups that react with acrylics to enhance dispersion are quite limited. In this work, a versatile chemical modification route is described that introduces acryloyl functional groups on CNCs that can in turn be polymerized in subsequent steps to create acrylic–CNC composites. The hydroxyl group on CNC surfaces was reacted with the isocyanate moiety on 2-isocyanatoethyl methacrylate (IEM), a bifunctional molecule possessing both the isocyanate group and acryloyl group. The resulting modified CNCs (mCNCs) showed enhanced hydrophobicity and dispersibility in organic solvent relative to unmodified CNCs. Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy, solid-state 13C nuclear magnetic resonance (NMR) spectroscopy, and elemental analysis verified the surface modification and allowed an estimation of the degree of modification as high as 0.4 (26.7% surface hydroxyl substitution CNC). The modified CNCs were copolymerized with methyl methacrylate, and the composites had improved dispersion relative to composites with unmodified CNCs and enhanced (104%) tensile strength at 2 wt % CNC when compared to the neat poly(methyl methacrylate) (PMMA), indicating a benefit of the reactive acryloyl groups added to the CNC surface. Overall, the modification strategy was successful in functionalizing CNCs, opening possibilities for their use in organic media and matrices.

Synthesis, characterization and application of glucosyloxyethyl acrylate graft chitosan against pipeline steel corrosion

In this study, glucosyloxyethyl acrylate graft chitosan (GA-CHS) was synthesized by reacting chitosan with glucosyloxyethyl acrylate, previously prepared via catalyzed α-d-glucopyranoside transesterification with excess 2-hydroxyethyl acrylate. This graft GA-CHS copolymer was utilized as a corrosion inhibitor for API 5 L X70 pipeline steel in chloride-enriched (1 M HCl) acid solution. GA-CHS adsorption on the steel surface led to significant inhibition of chloride-induced corrosion compare to unmodified chitosan (CHS). In the presence of GA-CHS, corrosion inhibition increased with its concentration due to the formation of compact protective films; compositional and morphological evidences have been provided. Without this graft copolymer in corrosive electrolytes, the steel coupons corroded due to unrestricted chloride-induced attacks, leading to severe surfaces pits. The linear GA-CHS polysaccharide moiety could have been a contributing factor and the greater edge over unmodified chitosan, regarding enhanced corrosion inhibition as well as its hydroxyl/amino chemical groups in combination with its acrylate functionality.

NIR Sensitizer Operating under Long Wavelength (1064nm) for Free Radical Photopolymerization Processes.

Free radical polymerization upon near-infrared (NIR) light is still the subject of intense research efforts and remains a huge challenge particularly for long wavelengths (>1000nm). In this study, a NIR sensitizer operating upon long wavelength (1064nm) is proposed for an efficient polymerization of acrylate monomers. A new three-component photoinitiating system is developed comprising the NIR sensitizer in combination with an Iodonium salt (Iod) and an amine. Remarkably, the NIR sensitizer (IR 1064) absorbing strongly in all the near infrared region (700-1200nm) offers the possibility to use a broad range of irradiation wavelengths, i.e., examples are provided at 785 and 1064nm. Such long wavelengths are characterized by many advantages such as a deeper penetration of light and therefore a better curing of the monomer but it is also much safer than UV light. Excellent performance is observed for the three-component IR 1064/Iod/Amine system under air: high conversion of acrylate functions associated with a fast polymerization time. The use of IR 1064 as NIR sensitizer with a broad NIR absorption is-to the best of current knowledge-never proposed in the literature. The photoinitiating performances are studied using real-time Fourier transform infrared spectroscopy.

Designing superhydrophobic and flame retardant photo-cured hybrid coatings

The study investigates the effect of the addition of phenyl phosphine oxide (DAPPO) with acrylate functionality, polyhedral oligomeric silsesquioxane (POSS) (acr-POSS) with acrylate functionality and 1H,1H,2H,2H-Perfluorodecyl acrylate (PFOA) on the superhydrophobicity and fire-resistance of photo-curable urethane-acrylate coatings. The addition of DAPPO to urethane-acrylate (50 wt.%) improved flame resistance. The additions of acr-POSS and PFOA improved surface hydrophobicity through increasing surface roughness by the addition of acr-POSS and decreasing surface energy by the addition of PFOA. The flammability and surface properties of the photo-curable hybrid coatings were evaluated by measuring limiting oxygen index (LOI) and water contact angle (WCA), respectively. Compared with the only urethane-acrylate-containing coating, the final hybrid coating had an increased water contact angle from 72.7°±2 to 147.2°±2 and increased LOI from 17,0 ± 0.08–24,3 ± 0.08. In the final hybrid coating, extinguishing occurred in less than 10 s.

Synthesis, properties and biodegradability of cross-linked amphiphilic Poly(vinyl acrylate)-Poly(tert-butyl acrylate)s by photo-initiated radical polymerization

The novel amphiphilic poly(vinyl acrylate)-poly(tert-butyl acrylate) based networks are produced by light-induced photo-initiated radical polymerization between poly(vinyl acrylate) (PVAcr), obtained by using hydroxyl moieties of poly(vinyl alcohol) (PVA), and tert-Butyl acrylate (tBA) monomer. PVA is modified by acryloyl chloride to obtained the corresponding acrylate functionalities (PVAcr). The achieved PVAcr is crosslinked with different amount of tBA (PVAcr:tBA = 0.005:1 and 0.005:2 by mole) to give desired structures (PVAcr-PtBA-1 and PVAcr-PtBA-2) in the presence of 2,2-Dimethoxy-2-phenylacetophenone (DMPA) at λ = 350 nm under nitrogen atmosphere. The structure, wettability, thermal and biodegradability properties of the pristine PVA and achieved networks are evaluated as a function of tBA loading by Fourier transform infrared (FT-IR) spectroscopy, water contact angle (WCA) measurement, thermogravimetric (TGA) and differential scanning calorimetry (DSC) analyses and biodegradation test, respectively. The results indicate that PVAcr-PtBA-2 obtained by higher tBA loading is less hydrophilic and biodegradable, but have improved thermal properties compared to pure PVA, and PVAcr-PVAcr control sample and PVAcr-PtBA-1.

PEGylated gold nanoparticles promoted rapid macromolecular chain-end transformation and formation of injectable hydrogels.

Azide-alkyne click cycloaddition and Michael addition reactions are useful for the synthesis and modification of biologically relevant macromolecules. Acceleration of these reactions at the macromolecular chain-ends and backbone has been achieved by gold [Au-(PEG-SH)n] nanoparticles (NPs) stabilized with multi-thiol-functional poly(ethylene glycol) containing tertiary amine groups in its backbone. The Au NPs successfully activate electron rich alkyne and acrylate functionalities of macromolecules at low substrate concentration leading to the enhancement of the reaction rate. The Au NPs successfully accelerate the gelation rate of reactive prepolymers leading to the rapid formation of injectable hydrogels. The Au nanocomposite hydrogels exhibited higher ultimate modulus and porosity than those of the pristine hydrogels. The grafting density (chains per nm2) of the stabilizer onto the Au NP surface plays a crucial role towards the activity of the NPs. The conversion of the chain-end functionality and gelation rate increase with decreasing grafting density onto the NP surface. A high grafting density lowers the activity of the Au NPs through blocking the active metal surface. The developed Au NPs may be a potential agent for the rapid preparation of biologically relevant macromolecular entities.

Synthesis of non-isocyanate polyurethanes and their application in radiation-curable aerospace coatings

Although the current polyurethane coatings used in the aerospace applications meet the stringent performance requirements, they don’t comply with the environmental demands, e.g., low VOC contents. Moreover, containing a significant amount of solvent, they usually need long drying times, which causes significant production burdens. Furthermore, many of these coatings contain isocyanates, which are hazardous and are likely to be regulated soon.In this study, a series of sustainable UV-curable non-isocyanate urethane acrylate (NIPU-AC) oligomers, with different structures and acrylate equivalent weights, were synthesized and used as a primary building block of UV-curable coatings for aerospace applications. Synthesis of the NIPU-AC oligomers was carried out in three steps: First, multi-functional cyclic carbonates (MFCC) were prepared by carbonation of aliphatic epoxy compounds under mild temperature and pressure conditions in the presence of a catalyst. In the next step, amine-terminated polyurethane oligomers (PUPAs) were synthesized by the reaction of MFCCs with a stoichiometric excess amount of aliphatic and cycloaliphatic amines. (meth)acrylate functionality was then introduced by direct reaction of amine groups at the chain ends of PUPAs with methacrylic anhydride (MAAH). The amine value titration and FTIR confirmed the successful synthesis of NIPU-AC oligomers with >95% yield. Finally, UV-curable NIPU coatings, as a new generation of sustainable coatings for aerospace applications, were developed and evaluated for aerospace-critical performance properties, such as low-temperature flexibility and resistance to specific chemicals/fluids.The results showed that flexibility at -54 ℃ (no cracks or delamination at 1/8”), and good chemical resistance (MEK double rubs > 90, and no significant change in the appearance regarding the fluids) could be reached through the proper design of NIPU-ACs, selection of appropriate reactive diluents, and UV-cure conditions. These fast-curable NIPU coatings, which contain low VOCs and HAPS and no isocyanates, could be sustainable alternatives for current aerospace polyurethane coatings.

Green Synthesis of Glycopolymers Using an Enzymatic Approach

Abstractβ‐Glucosidase and horseradish peroxidase (HRP) are used as biocatalysts in aqueous solution for the enzymatic synthesis of glycomonomers and the respective enzymatic polymerization toward glycopolymers. The biocatalytically synthesized monomers contain (meth)acrylate functionalities that are able to be polymerized by an enzyme‐initiated polymerization using an HRP/hydrogen peroxide/acetylacetone ternary system. The structure of the glycomonomers and the respective glycopolymers as well as the monomer conversion after the reaction are determined by1H NMR spectroscopy. The synthesized glycopolymers have a dispersity and a number‐average molecular weight up to 5.8 and 297 kg mol−1, respectively. Thermal and degradation properties of the glycopolymers are studied by differential scanning calorimetry and thermogravimetric analysis. In addition, preparation of glycopolymers via conventional free radical polymerization is performed and the properties of the obtained polymers are compared with the enzymatically synthesized glycopolymers.

Polymerizable C70 derivatives with acrylate functionality for efficient and stable solar cells

Fullerene-based organic solar cells are generally suffering from severe microstructure evolution occurring in their bulk heterojunction active layers and thus are extremely stable. To address it, four polymerizable C70 fullerene derivatives, [6,6]-phenyl-C71-ethyl acrylate (PC71EA), [6,6]-phenyl-C71-propyl acrylate (PC71PrA), [6,6]-phenyl-C71-butyl acrylate (PC71BA), and [6,6]-phenyl-C71-pentyl acrylate (PC71PeA), have been designed, synthesized, and investigated. These fullerene compounds have a molecular structure, shape and size very like the conventional C70 fullerene acceptor, [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM), and have been found no different in their light absorption, redox potentials, and frontier orbital energy levels. Using these fullerene acrylates individually as acceptor and poly(3-hexylthiophene) as donor, organic solar cells have been fabricated and gave optimal efficiencies ranging from 3.32% to 4.16%, comparable to PC71BM-based reference cells (4.06%). Owing to their acrylate functionality, these fullerene derivatives can turn into insoluble upon heating, and thus endow their solar cell devices much better thermostability than PC71BM-based reference cells. The best one, coming from PC71PeA devices, reported an optimal efficiency of 4.16%, and maintained 91.7% efficiency after heat treatment at 150 °C for 35 h. As a sharp contrast, the PC71BM reference cell dropped its optimal efficiency from 4.06% to 0.48% only after 5 h heat treatment. X-ray diffraction, optical and atomic force microscopy, and space-charge-limited current method have been carried out to understand active layer structure, morphology, and charge mobility change during heat treatment.

Linseed Oil‐Based Thermosets by Aza‐Michael Polymerization

AbstractAza‐Michael addition on acrylated linseed oil (AELO) is performed to synthetize biobased bulk thermosets without any catalyst. First, acrylation of epoxidized linseed oil (ELO) allows to obtain acrylate functions with vicinal hydroxyl groups which enhance the reactivity of acrylates. The autocatalytic effect of hydroxyl groups on acrylate monomers is highlighted by kinetic studies monitored by NMR and FTIR analyses on model molecules. Then, Priamine 1071, amine terminated poly(propyleneoxide) (PPO) and meta‐xylylenediamine (MXDA) are used as cross‐linkers with AELO. Curing kinetics are studied by DSC analyses to compare the reactivity of these structures. Priamine 1071 shows the highest reactivity; curing at room temperature is performed and high conversion is reached. Two enthalpies are observed with MXDA and only one at high temperature for PPO‐based materials. Thermosets with a large range of mechanical properties are finally obtained from soft materials with PPO‐diamine to hard materials with MXDA.Practical Applications: Thermosets are obtained by curing AELO with various diamines via aza‐Michael reaction. Model reaction allows to demonstrate catalytic effect of hydroxyl groups on Aza‐Michael reaction of acrylated oil with amines. Hence, linseed oil is a promising resource in terms of sustainable development in polymer science.

Periodic Mesoporous Organosilicas from Polyion Complex Micelles – Effect of Organic Bridge on Nanostructure

A new family of polyion complex (PIC)‐based periodic mesoporous organosilicas, PICPMOs, obtained by the hydrolysis‐condensation of organosilanes containing organic bridging units (phenylene, ethenylene and ethylene) in the presence of polyion complex (PIC) micelles as structure‐directing agents (SDAs), is described. The electrostatic interactions between the acrylic acid functions of a poly(ethylene oxide)‐b‐poly(acrylic acid) double‐hydrophilic block copolymer (DHBC) and the primary amine functions of a polyamine micellization agent control the formation of the core of the micellar complex, while the PEO chains of the micelle corona mediate the formation of the organic/inorganic interface that controls the evolution of the material. Herein, the micellization agent employed is an antibiotic drug, neomycin B. An important feature of this procedure is that the processing involves a “one‐pot” reaction, enabling the formation of the material and the direct encapsulation of the anti‐bacterial agent. This results in a reduction in the number and cost of processing steps, while offering the opportunity to easily tune the hybrid mesostructure. The PICPMO materials obtained are organized on different length scales, from long‐range‐ordered 2D hexagonal structuring in the case of the phenylene bridge to weakly organized wormlike structures in the case of the ethylene unit. The effect of organic bridge structure on the nanostructure and physical properties of the PICPMO is discussed.

Controlled Synthesis of Block Copolymers by Mechanistic Transformation from Atom Transfer Radical Polymerization to Iniferter Process

A straightforward transformation protocol combining two distinct living polymerization methods for the controlled synthesis of block copolymers is described. In the first step, bromo-terminated poly(methyl methacrylate) is prepared by atom transfer radical polymerization (ATRP). Then, a bromide end group is substituted with a triphenylmethyl (trityl) functionality under visible light irradiation using dimanganese decacarbonyl (Mn2 (CO)10 ) photochemistry. The resulting polymers with trityl end groups are used as macroiniferter for the polymerization of styrene and tert-butyl acrylate (tBA) to yield desired block copolymers with narrow molecular weight distribution. Moreover, the amphiphilic copolymers with acrylic acid functionalities are obtained by the hydrolyzation of poly(tert-butyl acrylate) containing block copolymers with trifluoroacetic acid.

The effect of acrylate functionality on frontal polymerization velocity and temperature

ABSTRACTFrontal polymerization is a method of converting monomer(s) to polymer via a localized reaction zone that propagates from the coupling of thermal diffusion with the Arrhenius kinetics of an exothermic reaction. Several factors affect front velocity and temperature with the role of monomer functionality being of particular interest in this study. Polymerizing a di and triacrylate of equal molecular weight per acrylate revealed that as the proportion of triacrylate was increased the velocity and temperature increased. This is attributed to increased crosslinking and autoacceleration. Comparing several different acrylate monomers, both neat and diluted with dimethyl sulfoxide (DMSO) so as to maintain constant acrylate group concentration, shows that velocity increases with increased functionality from mono to difunctional monomers. This trend breaks when applied to tri‐ and tetraacrylates, with fronts containing trifunctional monomer being the fastest. Acrylates containing hydroxyl functionality, as in the case of pentaerythritol‐based triacrylates, are slower than acrylates without. This is attributed to a chain‐transfer event and was tested using octanol and a hydroxyl‐free acrylate. It has also been shown that small amounts of water cause a lowering of front velocity due to energy lost via vaporization, which lowers the front temperature. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 982–988

Crosslinkable-Chitosan-Enabled Moisture-Resistant Multilayer Gas Barrier Thin Film.

Chitosan-based films exhibit good oxygen barrier that degrades when exposed to high humidity. In an effort to overcome this drawback, a multilayer nanocoating consisting of crosslinkable chitosan (CHQ) and poly(acrylic acid) [PAA] is deposited on polyethylene terephthalate (PET) using layer-by-layer assembly. Chitosan is functionalized with glycidyl methacrylate to introduce acrylic functionalities within the film. The deposited films are crosslinked using a free radical initiator and this crosslinking is confirmed by FTIR and reduced film thickness. A 10-bilayer (BL) crosslinked CHQ/PAA film, which is only 165nm thick, results in a 36× reduction of the oxygen transmission rate of PET at 90% relative humidity. To achieve these same results without crosslinking, a 15-BL unmodified chitosan (CH)/PAA film, which is almost 5× thicker, must be deposited on PET. This environmentally friendly, transparent nanocoating is promising for food packaging or protection of flexible electronics, especially in high-humidity environments.

PH-mediated control over the mesostructure of ordered mesoporous materials templated by polyion complex micelles.

Ordered mesoporous silica materials were prepared under different pH conditions by using a silicon alkoxide as a silica source and polyion complex (PIC) micelles as the structure-directing agents. PIC micelles were formed by complexation between a weak polyacid-containing double-hydrophilic block copolymer, poly(ethylene oxide)-b-poly(acrylic acid) (PEO-b-PAA), and a weak polybase, oligochitosan-type polyamine. As both the micellization process and the rate of silica condensation are highly dependent on pH, the properties of silica mesostructures can be modulated by changing the pH of the reaction medium. Varying the materials synthesis pH from 4.5 to 7.9 led to 2D-hexagonal, wormlike or lamellar mesostructures, with a varying degree of order. The chemical composition of the as-synthesized hybrid organic/inorganic materials was also found to vary with pH. The structure variations were discussed based on the extent of electrostatic complexing bonds between acrylate and amino functions and on the silica condensation rate as a function of pH.

Castor oil-based waterborne hyperbranched polyurethane acrylate emulsion for UV-curable coatings with excellent chemical resistance and high hardness

Synthesis, characterization, and coating performance of castor oil (CO)-based waterborne hyperbranched polyurethane acrylate (WHPUA) emulsions are highlighted in this work. Herein, a second-generation CO-based hyperbranched polyester (C20) was synthesized by introducing the renewable CO as a B3 core and dimethylolpropionic acid as an AB2 monomer via a pseudo-one-pot condensation procedure. Three types of CO-based WHPUA emulsions were prepared through the addition of the hyperbranched C20 with maleic anhydride (MA) and the isocyanate-bearing semiadduct (IPDI-HEA) at different MA/IPDI-IH molar ratios without the addition of any emulsifiers. The prepared emulsions were further formulated into UV-curable coating formulations and exposed to a medium-pressure mercury lamp. Consequently, the obtained UV-cured coatings exhibited outstanding adhesion performance, excellent transparency, and an acceptable degree of final double bond conversion. Owing to a relatively low concentration of hydrophilic units and a large number of acrylate functionalities in the waterborne oligomer, the obtained films were endowed with high crosslinking density and low hydrophilic nature, thus producing enhanced tensile strength, pencil hardness, water resistance, and chemical resistance. Due to their combination of renewable materials, a waterborne system and a UV-curing technique, these CO-based WHPUA emulsions offer promising opportunities to be used as environmentally friendly coatings.

Hydrothermal carbon superstructures enriched with carboxyl groups for highly efficient uranium removal

Carbon superstructures with graphitized lamellar microstructures were fabricated through a modified hydrothermal method. The dual oxidation process combining acrylic acid functionalization and air thermal treatment introduced plentiful carboxyl groups on the surface of the carbon superstructures. Adsorption capacity of U(VI) on the as prepared carbon superparticles reached 197.7 mg g−1, which was 9-fold higher than that of raw glucose-derived hydrothermal carbon microspheres. The thermo-dynamic and kinetic studies demonstrated that the uptake of uranyl ions was a spontaneous and endothermic chemisorption dominated process with the abundant carboxyl groups acting as main binding sites. Impressively, the carbon superstructure adsorbents showed excellent recycling performance. To sum up, this paper proposed a novel high-performance U(VI) adsorbent from hydrothermal carbon, which exhibited potential in real application due to their outstanding reusability and scale-up capability.