Pentaerythritol Tetraacrylate Research Articles

Sensitivity-Enhancing Modified Holographic Photopolymer of PQ/PMMA

Phenanthrenequinone-doped poly(methyl methacrylate) (PQ/PMMA) photopolymers are potential holographic storage media owing to their high-density storage capacities, low costs, high stability, and negligible shrinkage in volume holographic permanent memory. However, because of the limitations of the substrate, conventional Plexiglas materials do not exhibit a good performance in terms of photosensitivity and molding. In this study, the crosslinked structure of PMMA was modified by introducing a dendrimer monomer, pentaerythritol tetraacrylate (PETA), which increases the photosensitivity of the material 2 times (from ~0.58 cm/J to ~1.18 cm/J), and the diffraction efficiency is increased 1.6 times (from ~50% to ~80%). In addition, the modified material has a superior ability to mold compared to conventional materials. Moreover, the holographic performance enhancement was evaluated in conjunction with a quantum chemical analysis. The doping of PETA resulted in an overall decrease in the energy required for the reaction system of the material, and the activation energy decreased by ~0.5 KJ/mol in the photoreaction stage.

Novel Injectable Hydrogel Formulations and Gas Chromatography Analysis of the Residual Crosslinker in Formulations Intended for Pharmaceutical and Cosmetic Applications.

Novel hyaluronic acid (HA) crosslinked with pentaerythritol tetra-acrylate (PT) injectable hydrogels was invented. These injectable hydrogel/dermal filler formulations were synthesised using HA and the acrylate PT as a crosslinker under basic pH conditions using thermal crosslinking methods (oven heating), which provides a simple, safe, and eco-friendly method for crosslinking in 4 h under 45 °C. Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analyses were conducted to represent the difference between the formulations in terms of peak formation and pore size, respectively. The crosslinking was partial as is considered to be typical for dermal injectable fillers. The rheological properties of these formulations showed that these novel dermal injectables are highly promising, and the newly developed fillers could be used with better results for dermal anti-wrinkle corrections, shaping, and volumising reasons. Furthermore, crosslinker (PT) residual analysis was carried out to state the formulations that are valid and acceptable for intradermal usage. The results from the GC method validation revealed it was a suitable method for this study. The GC analysis of all five injectable hydrogel/filler formulations demonstrated the formulations HA-PT 1, 2, 3 and 4 were formulated using (0.05-0.1)% w/w PT containing residual PT monomers within the safe limits that were determined to be below (0.008% w/w). This work has shown the development of a novel injectable hydrogel/filler formulation for pharmaceutical and cosmetic applications can be prepared in a more sustainable and simple way using pentaerythritol tetra-acrylate as a crosslinker agent, which holds great promise for the industry's future advancement.

Fast-curing bio-based thermoset foams produced via the Michael 1,4-addition using fatty acid-based acetoacetate and acrylate

This study introduces an approach for creating bio-based polymer foams exploiting the Michael reaction that could be utilized as thermal insulation. The thermoset foams were developed using a second-generation bio-based feedstock – tall oil. Tall oil is a by-product of wood pulping in paper manufacturing and mainly comprises unsaturated fatty acids like oleic and linoleic acid. The study explores the use of tall oil-based acetoacetates (Michael donor) combined with various acrylates (Michael acceptor), petrochemical-based (bisphenol-A ethoxylate diacrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate), and bio-based (epoxidized soybean oil acrylate, epoxidized tall oil free fatty acids-based acrylate), to develop polymer foams that meet today's sustainability requirements. The developed polymer foams underwent extensive characterization. Matrix curing parameters were assessed by measuring changes in dielectric polarization during curing. Foaming parameters, including start and rise times, were precisely measured. The chemical composition of the foams was analysed using Fourier-transform infrared spectroscopy. Their thermal, thermo-mechanical, and mechanical properties were evaluated through thermal gravimetric analysis, differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and compression tests. Additionally, the content of closed-cell and the coefficient of thermal conductivity were determined, further characterizing the foams as potential thermal insulation materials. Foams from bio-based donors with petrochemical-based acceptors exhibited a range of enhanced properties. They not only achieved high glass transition temperatures (up to 85 °C by DSC and up to 108 °C by DMA) but also displayed a spectrum of mechanical strengths (compression strength ranging from moderate to as high as ∼ 0.40 MPa) and good thermal isolation properties (thermal conductivity coefficient ∼ 31mW/(m·K)). Bio-based foams, derived from renewable resources, were characterized by properties fitting for flexible foam applications, such as low glass transition temperatures (down to −9.7 °C by DSC and down to 9.8 °C by DMA), reduced compression strength (approximately 0.011 MPa), and increased thermal conductivity (up to 46.7mW/(m·K)), indicating their potential utility in applications where flexibility is a key requirement.

Comparing the Kinetic Hydrate Inhibition Performance of Linear versus Branched Polymers.

Kinetic hydrate inhibitors (KHIs) are a chemical method of preventing gas hydrate plugging of oil and gas production flow lines. The main ingredient in a KHI formulation is one or more water-soluble amphiphilic polymers. Poly(N-vinyl caprolactam) (PVCap) is an unbranched polymer and a well-known industrial KHI, often used as a yardstick to compare the performance of new polymers. The effect of branching PVCap on KHI performance has been investigated by polymerizing the VCap monomer in the presence of varying amounts of trimethylolpropane triacrylate, pentaerythritol tetraacrylate, or bis-pentaerythritol hexaacrylate cross-linkers to give PVCap polymers with 3, 4, and 6 branches, respectively. If the ratio of cross-linker to VCap was too high (6:1 to 8:1), gelling and/or poor water solubility was observed, giving short polymer chains and poor KHI efficacy. For higher ratios (30:1 to 60:1), it was found that the concentration of the polymer needed to give total inhibition of structure II tetrahydrofuran hydrate crystal growth could be lowered by using tribranched rather than linear PVCap. Slow constant cooling (1 °C/h) gas hydrate experiments with a synthetic natural gas in steel rocking cells at 76 bar were also carried out. A small improvement in KHI performance was observed for one of the branched PVCaps compared with a linear PVCap. Branched and linear poly(N-isopropylmethacrylamide) (PNIPMAm) polymers were also investigated in the gas hydrate system, but there was no benefit observed when branching this polymer class.

Pentaerythritol tetraacrylate microcavity sensor for high performance relative humidity detection

A pentaerythritol tetraacrylate (PETA) microcavity sensor for high performance relative humidity (RH) detection is presented. The fiber tip all-polymer microcavity, with a maximum size of 99.27 µm, consists of a circular truncated cone on the fiber tip end surface and is manufactured by photopolymerization of PETA using two-photon polymerization technology, which is characterized by miniaturization and rapid manufacturing. Experimental results show that its RH sensitivity reaches 108.05 pm/%RH in the range of 14.7–84.3%RH. In particular, respiration monitoring experiments show that its response time and recovery time are 0.55 s and 2.5 s, respectively. The sensor shows the inherent advantages of compact structure, fast response, good repeatability, low hysteresis error, good stability, and high sensitivity. Therefore, it is a promising candidate for potential applications in chemical, medical and biological fields related to RH detection.

High-safety lithium metal pouch cells for extreme abuse conditions by implementing flame-retardant perfluorinated gel polymer electrolytes

Lithium metal anodes coupled with nickel-rich cathodes promise high-energy-density batteries. Nonetheless, the overall safety of lithium metal batteries is compromised by the use of conventional thermally unstable and flammable carbonate-based electrolytes, which hinders their practical applications, especially under abuse conditions. Herein, a flame-retardant perfluorinated gel polymer electrolyte (PFGPE) is developed by in situ copolymerization of perfluorobutyl acrylate (PFBA) monomer with pentaerythritol tetraacrylate (PETEA) crosslinker. PFBA decomposes at high temperatures to generate fluorine radicals that eliminate hydrogen and hydroxyl radical chain combustion reactions in the gas phase, reducing the combustion risk of electrolytes. Additionally, the co-pyrolysis of the carbonate-based electrolytes and the copolymerization matrix produces a P- and F- containing char layer in the condensed phase, blocking the heat and oxygen required for combustion. A large-format PFGPE modified Li metal pouch cell (4.4 Ah, 381 Wh kg−1) achieves 120 cycles with 83.4% of capacity retention under a lean electrolyte of 3 g Ah−1 and a negative/positive capacity ratio of 1.82. Moreover, the modified pouch cell exhibits enhanced thermal safety characteristics and passes international standard tests (GB/T 31485–2015) for mechanical nail penetration and thermal abuse. This innovative approach represents a significant milestone towards the advancement of high-safety Li metal batteries.

Photopolymerization-induced phase separation kinetics explored by intermittent irradiation

In this work, we explore the kinetics of the photopolymerization-induced phase separation (photo-PIPS) process and the interplay of mechanisms controlling the development of the microstructure in a photosensitive resin comprised of pentaerythritol tetraacrylate (PETA) and 2-ethylhexyl methacrylate (2-EHMA) monomers with polypropylene glycol (PPG, Mn = 4000 g/mol) linear polymer additive and diphenyl(2,4,6-trimethylbenzoyl) phosphine oxide (TPO) photoinitiator. We control the kinetics of photopolymerization by interrupting the irradiation at various stages of the process and varying the light intensity. Evolution of the microstructure is monitored by transmittance testing and scanning electron microscopy (SEM) inspection of fractured surfaces that are exposed to methanol for the purpose of removing the phase-separated PPG content. The evolution of the network is monitored by real-time Fourier-transform infrared (FTIR) spectroscopy during irradiation and intermittent probing after the cessation of irradiation. Three mechanisms controlling the evolution of the microstructure are identified: phase separation, photoinitiator consumption, and microstructural refinement. Phase separation begins immediately after the onset of network development and leads to a rapid reduction of transmittance due to the formation of PPG-rich subdomains. Microstructural refinement takes place at later stages leading to a reduction of these subdomains, a gradual increase of the PPG concentration within subdomains and an associated increase of transmittance. TPO consumption takes place during irradiation and accounts, to a smaller extent, for the recovery of the transmittance. Interrupting the irradiation allows generation of materials with various degrees of conversion and sizes of phase-separated subdomains, which provides a new way to control material properties.

Nonflammable Polyfluorides-Anchored Quasi-Solid Electrolytes for Ultra-Safe Anode-Free Lithium Pouch Cells without Thermal Runaway.

The safe operation of rechargeable batteries is crucial because of numerous instances of fire and explosion mishaps. However, battery chemistry involving metallic lithium (Li) as the anode is prone to thermal runaway in flammable organic electrolytes under abusive conditions. Herein, an in situ encapsulation strategy is proposed to construct nonflammable quasi-solid electrolytes through the radical polymerization of a hexafluorobutyl acrylate (HFBA) monomer and a pentaerythritol tetraacrylate (PETEA) crosslinker. The quasi-solid system eliminates the inherent flammability of ether electrolytes with zero self-extinguishing time owing to the gas-phase radical capturing ability of HFBA. Additionally, the graphitized carbon layer generated during the decomposition of PETEA at high temperatures obstructs the heat and oxygen required for combustion. When coupled with Au-modified reduced graphene oxide anodic current collectors and lithium sulfide cathodes, the assembled anode-free Li-metal cell based on the quasi-solid electrolyte exhibits no signs of cell expansion or gas generation during cycling, and thermal runaway is eliminated under multiple mechanical, electrical, and thermal abuse scenarios and even rigorous strikes. This nonflammable quasi-solid configuration with gas- and condensed-phase flame-retardant mechanisms can drive a technological leap in anode-free Li-metal pouch cells and secure the practical applications necessary to power this society in a safe manner.

Synthesis and properties of crosslinked waterborne polyurethane/acrylate copolymer latexes using AIBN initiator based on a solvent-/emulsifier-free method

In this study, a series of crosslinked waterborne polyurethane/acrylate copolymer latexes with different compositions were fabricated via emulsion polymerization using oil-soluble initiator (AIBN) based on a solvent-/emulsifiers-free method. Using the blend of styrene (St), butyl acrylate (BA) and crosslinkers (pentaerythritol triacrylate (PET3A) and pentaerythritol tetraacrylate (PET4A)) instead of acetone as a diluent and modifier, polyurethane prepolymers terminated with hydroxyethyl acrylate composite emulsions were prepared using polypropylene glycol (PPG), toluene diisocyanate (TDI), 2,2-dihydroxymethylpropionic acid (DMPA) and diethylene glycol (DEG) without other solvents. It was found that for all the emulsion polymerization of waterborne polyurethane and acrylates initiated by AIBN, the monomer conversions exceeded 96% when the concentration of AIBN was in the range of 0.5% to 0.9% (w/w) and the optimal reaction temperature was 75 °C. The introduction of St, BA and crosslinkers would form the polymer network, improving the tensile strength, water absorption of the copolymer latex films. Dynamic light scattering analyses showed that the copolymer latexes exhibited a unimodal distribution and showed no precipitates and unstable aggregates. The average particle size distribution was in the range of 131–154 nm. Transmission electron microscopy studies have confirmed the similar results and the latex particles possessed the core–shell morphology structure.

Fluorine grafted gel polymer electrolyte by in situ construction for high-voltage lithium metal batteries

Gel polymer electrolytes (GPEs) are promising candidates for next generation lithium metal batteries (LMBs) due to their reassuring safety and high ionic conductivity at room temperature. However, they are still plagued by incompatible interfaces and poor compatibility with Ni-rich cathodes, imposing great restrictions on the scalability of high-voltage cathodes. To overcome these problems, a GPE with a polyacrylonitrile porous membrane, together with 2,2,3,4,4,4-hexafluorobutyl acrylate grafted pentaerythritol tetraacrylate, is fabricated via in-situ thermal polymerization. By virtue of the effective transport channels provided by PAN and PETEA molecules, our GPE exhibits both a high lithium-ion transference number and a high ionic conductivity of 0.87 and 4.06 × 10−3 S cm−1, respectively at 30 °C. Moreover, the GPE ensures a high electrochemical window, stable at potentials up to 5.35 V, enabling the application of LiNi0.8Co0.1Mn0.1O2 (NCM811) cathodes. Due to the uniform cathode electrolyte interface (CEI) formed by our GPE on the surface of NCM811, the assembled NCM811|GPE|Li batteries present an excellent cycling life of 300 cycles in the voltage range of 3 ∼ 4.5 V with a capacity retention of 84% at 2C. Our study provides a novel strategy for constructing fast Li+ transport channels and stable CEI membranes in LMBs operating at high voltages.

In-situ construction of cellulose acetate propionate-based hybrid gel polymer electrolyte for high-performance lithium metal batteries

Quasi-solid-state gel polymer electrolytes (GPEs) have a great deal of promise for usage in future energy systems due to their high safety. However, ex-situ prepared GPEs still suffer from interfacial incompatibility. Herein, to create stable electrolyte-electrode interfaces and ensure adequate contact, a novel GPE was prepared by in-situ polymerization using pentaerythritol tetraacrylate (PETEA) and cellulose acetate propionate (CAP) as raw materials. PETEA and CAP with a certain mass ratio were added into liquid electrolyte, and the in-situ polymerization of PETEA and CAP was initiated by azobisisobutyronitrile (AIBN). The multi-side chain structure of PETEA and the hydrogen bonding interaction between PETEA and CAP contributed to a robust cross-linked framework, while CAP improved Li+ transport through its polar oxygen-containing groups. The obtained GPE 1:1 exhibited high ionic conductivity (1.03 ×10−3 S/cm at 25 ℃), superior Li+ transference number (0.73), and good stability to Li metal. Meanwhile, a stable SEI film with rich LiF was established, ensuring a long-term cycling lifespan. After 500 cycles at 1 C, the assembled LiFePO4/GPE 1:1/Li cell revealed a high capacity retention of 90.6%. These results provide a guideline for the future design of novel cellulose-based GPEs for high performance lithium metal batteries.

3D printable polyvinyltoluene-based plastic scintillators with pulse shape discrimination

A feasibility of preparing bulk photopolymerized plastics scintillators that contain vinyltoluene with multifunctional monomers, pentaerythritol tetraacrylate is shown. This formulation offers a simple and fast way to prepare polyvinyltoluene-based plastics with efficient fast neutron/gamma pulse shape discrimination (PSD) within minutes. 30 wt% of 2,5-diphenyloxazole (PPO) was added in the mixtures of vinyltoluene and pentaerythritol tetraacrylate with different secondary dyes to understand the effect of dyes on the scintillation. Prepared resins were photopolymerized under different conditions, and the scintillation performance was compared to a commercially available standard, EJ-276. Additional functionality for thermal neutron sensitivity was introduced by the incorporation of 6Li and 6B nuclei. With optimized conditions, prepared plastics showed light output up to 90% relative to the same size of EJ-276. The best plastic scintillators had PSD figures of merit (FoMs) up to 2.77 compared to 3.25 of EJ-276. The 3D-printability of the tested formulations was demonstrated.

Cross-Linked Solid Polymer-Based Catholyte for Solid-State Lithium-Sulfur Batteries

All-solid-state lithium-sulfur batteries (ASSLSBs) are a promising next-generation battery technology. They exhibit high energy density, while mitigating intrinsic problems such as polysulfide shuttling and lithium dendrite growth that are common to liquid electrolyte-based batteries. Among the various types of solid electrolytes, solid polymer electrolytes (SPE) are attractive due to their superior flexibility and high safety. In this work, cross-linkable polymers composed of pentaerythritol tetraacrylate (PETEA) and tri(ethylene glycol) divinyl ether (PEG), are incorporated into sulfur–carbon composite cathodes to serve a dual function as both a binder and electrolyte, as a so-called catholyte. The influence of key parameters, including the sulfur–carbon ratio, catholyte content, and ionic conductivity of the electrolyte within the cathode on the electrochemical performance, was investigated. Notably, the sulfur composite cathode containing 30 wt% of the PETEA-PEG copolymer catholyte achieved a high initial discharge capacity of 1236 mAh gS−1 at a C-rate of 0.1 and 80 °C.

Interplay of photopolymerization and phase separation kinetics and the resulting structure-property relationship of photocurable resins

In this work we develop thermoset materials with heterogeneous microstructures on sub-micron scales by photopolymerization-induced phase separation (photo-PIPS). To this end, we designed a photo-curable resin based on pentaerythritol tetraacrylate (PETA), an acrylate monomer, combined with 2-ethylhexyl methacrylate (2-EHMA), a methacrylate diluent. Polypropylene glycol (PPG) was used as a phase separation agent. Phase separation was monitored by reactive light transmittance using a custom-built light transmission apparatus and through dynamic mechanical analysis (DMA). The photopolymerization kinetics and the microstructure morphology were characterized using real-time Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM), respectively. We observe double phase separation: PETA and 2-EHMA separate due to different reactivities, while PPG phase separates as the network develops due to immiscibility. A synergy is observed between the two processes: PPG phase separation leads to an enhanced separation of 2-EHMA. Phase separation leads to reduced transmittance due to scattering, which is primarily associated with the separation of 2-EHMA. Phase separation also causes the reduction of stiffness due to the formation of PPG subdomains. The kinetics is enhanced by increasing the PPG molecular weight and increasing the irradiation intensity.

In Situ Polymerized Flame Retardant Gel Electrolyte for High-Performance and Safety-Enhanced Lithium Metal Batteries.

A flame retardant gel electrolyte (FRGE) is deemed as one of the most promising electrolytes to relieve the problems of safety hazards and interfacial incompatibility of Li metal batteries. Herein, a novel solvent triethyl 2-fluoro-2-phosphonoacetate (TFPA) with outstanding flame retardancy is introduced in the polymer skeleton synthesized by in situ polymerization of the monomer polyethylene glycol dimethacrylate (PEGDMA) and the cross-linker pentaerythritol tetraacrylate (PETEA). The FRGE exhibits superb interfacial compatibility with Li metal anodes and inhibits uncontrolled Li dendrite growth. This can be ascribed to the restriction of free phosphate molecules by the polymer skeleton, thus realizing a stable cycling performance over 500 h at 1 mA cm-2 and 1 mAh cm-2 in the Li||Li symmetric cell. In addition, the high ionic conductivity (3.15 mS cm-1) and Li+ transference number (0.47) of the FRGE further enhance the electrochemical performance of the correspondent battery. As a result, the LiFePO4|FRGE|Li cell exhibits excellent long-term cycling life with a capacity retention of 94.6% after 700 cycles. This work points to a new pathway for the practical development of high-safety and high-energy-density Li metal-based batteries.

Additively Manufactured 3D Micro-bioelectrodes for Enhanced Bioelectrocatalytic Operation

The drive toward miniaturization of enzyme-based bioelectronics established a need for three-dimensional (3D) microstructured electrodes, which are difficult to implement using conventional manufacturing processes. Additive manufacturing coupled with electroless metal plating enables the production of 3D conductive microarchitectures with high surface area for potential applications in such devices. However, interfacial delamination between the metal layer and the polymer structure is a major reliability concern, which leads to device performance degradation and eventually device failure. This work demonstrates a method to produce a highly conductive and robust metal layer on a 3D printed polymer microstructure with strong adhesion by introducing an interfacial adhesion layer. Prior to 3D printing, multifunctional acrylate monomers with alkoxysilane (-Si-(OCH3)3) were synthesized via the thiol-Michael addition reaction between pentaerythritol tetraacrylate (PETA) and 3-mercaptopropyltrimethoxysilane (MPTMS) with a 1:1 stoichiometric ratio. Alkoxysilane functionality remains intact during photopolymerization in a projection micro-stereolithography (PμSLA) system and is utilized for the sol-gel reaction with MPTMS during postfunctionalization of the 3D printed microstructure to build an interfacial adhesion layer. This leads to the implementation of abundant thiol functional groups on the surface of the 3D printed microstructure, which can act as a strong binding site for gold during electroless plating to improve interfacial adhesion. The 3D conductive microelectrode prepared by this technique exhibited excellent conductivity of 2.2 × 107 S/m (53% of bulk gold) with strong adhesion between a gold layer and a polymer structure even after harsh sonication and an adhesion tape test. As a proof-of-concept, we examined the 3D gold diamond lattice microelectrode modified with glucose oxidase as a bioanode for a single enzymatic biofuel cell. The lattice-structured enzymatic electrode with high catalytic surface area was able to generate a current density of 2.5 μA/cm2 at 0.35 V, which is an about 10 times increase in current output compared to a cube-shaped microelectrode.

Influence of Monomer Structure, Initiation, and Porosity on Mechanical and Morphological Characteristics of Thiol‐ene PolyHIPEs

AbstractCombining high internal phase emulsion templating with thiol‐ene click chemistry produces porous polymers with high yields and degradable ester linkages. This study compares the influence of the monomer functionalities (tri versus tetra), internal phase volume, and initiation type (photo versus thermal) on the morphological and mechanical properties of poly(high internal phase emulsions) (polyHIPEs). For the synthesis of the polyHIPEs pentaerythritol tetrakis(3‐mercaptopropionate) (PETMP, tetrafunctional), trimethylolpropane tris(3‐mercaptopropionate) (TMPTMP, trifunctional), pentaerythritol tetraacrylate (PETA, tetrafunctional), and trimethylolpropane triacrylate (TMPTA, trifunctional) are used. The main factors influencing the properties of the polyHIPEs are the monomer structures and the internal phase volume, while the initiation type influences the morphology of the trifunctional system (pore size and morphology type) resulting in an interconnected cellular morphology in all cases except in the case of the photopolymerization of the emulsion with 85 vol% of the internal phase. The average pore diameter of the trifunctional system ranges from 8.0 to 27.8 µm, while for the tetrafunctional system it ranges from 8.1 to 12.3 µm. The compression moduli of the trifunctional system range from 0.093 to 0.240 MPa and for the tetrafunctional system they range from 1.906 to 7.670 MPa. The compression moduli decrease with increasing internal phase volume (porosity).

Novel Crosslinked HA Hydrogel Films for the Immediate Release of Active Ingredients

Novel crosslinked hyaluronic acid (HA) hydrogel films were previously invented by reacting the HA polymer with the PT (Pentaerythritol Tetra-acrylate) crosslinker over basic pH conditions in the oven. HA is considered a natural polymer present in cosmetic as well as pharmaceutical formulations. This current study aimed to highlight the effect of loading method (post-loading and in situ) of selected actives (salicylic acid and niacinamide B3) in the hydrogel films and then study their release kinetics. Differential scanning colometry (DSC) and Fourier transform infrared spectroscopy (FTIR) analysis evidenced the loading of the actives and full release from the HA hydrogel films, while the scanning electron microscopy (SEM) demonstrated the morphological changes to the films during the study by comparing the average molecular weight between crosslinks (M¯c), gel fraction, crosslinking density (Ve) and mesh size (ξ) of the films. The loading percentage of the SA and B3 showed high percentage loading of actives via both loading methods. In conclusion, the (95–100%) release of the actives achieved from the HA hydrogel films within 10 min revealed that the films are an efficient immediate release system of actives.

Preparation of siloxymethyl-modified silicone acrylate prepolymers with UV/moisture dual curability for applications in anti-smudge and anti-fingerprint coatings

UV-curing technology is an efficient, energy-saving and eco-friendly technology, which has been widely used in industrial production and daily life. However, UV curing is difficult to achieve with thick coatings, coloured coatings, and shadowed regions of coatings, which greatly limits the applicability of this process. As reported herein, UV/moisture dual curable siloxymethyl-modified silicone acrylate (SMSA) prepolymers were synthesized through the two-step sequential hydrosilylation of pentaerythritol tetraacrylate (PETTA), hydride-terminated polydimethylsiloxane (H-PDMS) and trimethoxysilane (TMOS). The prepolymer contains UV-curable acrylate groups and moisture-curable siloxymethyl groups, and thus it can be readily cured via exposure to UV light, moisture, or a combination of UV light and moisture. Combining the advantages of UV and moisture curing, the prepolymer is capable of curing rapidly and overcomes the problem of UV curing about shadowed areas and thick coatings. This combined UV/moisture dual curing process also solves the problem of oxygen inhibition and poor adhesion of conventional UV-curable silicone materials. The properties of UV/moisture dual cured coatings were characterized and found to exhibit excellent transparency, heat resistance, as well as hydrophobicity. The transparencies of these coatings are over 93% even the thicknesses are up to 100 µm. The coatings remain stable when temperatures reach up to 296.5 and 317.2 °C. The water contact angles of coatings are between 97° and 103°, and surface energies of the coatings vary from 25.43 to 21.27 mN/m. The UV/moisture dual cured coatings also have excellent resistance to smudge and fingerprints. Therefore, they will be suitable for the preparation of anti-smudge and anti-fingerprint coatings.

A room-temperature high performance all-solid-state lithium-sulfur battery enabled by a cross-linked copolymer@ceramic hybrid solid electrolyte

The use of solid electrolytes (SEs) is a key strategy for enabling the intrinsically safe operation of batteries comprising lithium metal anodes as they suppress the growth of lithium dendrites. Among the different types of SEs, polymer-based hybrid electrolytes (HEs) are highly promising due to their synergetic properties from the constituent polymer matrix and inorganic filler particles. However, the lithium-ion diffusion pathway in HEs is still dominated by the polymer, especially for polyethylene oxide (PEO)-based HEs. The main limitation of PEO is the strong temperature dependence of its ionic conductivity, preventing its use at room temperature (RT). Herein, a cross-linked polymer-based HE with a high ionic conductivity of 1.1 × 10-3 S cm-1 at RT is presented. The novel cross-linked copolymer, composed of pentaerythritol tetraacrylate (PETEA), tri(ethylene glycol) divinyl ether (TEG), and lithium bis(trifluoromethanesulfonyl)-imide (LiTFSI), serves as a matrix to achieve satisfactory mechanical strength. Integrated Li7La3Zr2O12 (LLZO) particles are covalently bound to the copolymer by a prior surface modification step. To demonstrate the suitability of the developed HE for RT application in advanced battery systems, a solid-state lithium-sulfur cell is built which exhibits an initial specific capacity of 688 mA h g-1. The ability of this HE to operate at RT can be expected to boost the development of safe all-solid-state batteries for many applications.