Polymer Backbone Research Articles

Poly(butylene 2,5-thiophenedicarboxylate-co-glycolate) copolyesters with good degradation and barrier properties

In this work, poly(butylene 2,5-thiophenedicarboxylate-co-glycolate) (PBTFGA) copolyesters were synthesized from 2,5-thiophenedicarboxylic acid, 1,4-butanediol and glycolic acid. The influence of the glycolic acid content on thermal properties, mechanical properties and degradation capacity of copolyesters was systematically investigated. The glass transition temperature of copolyesters closely matched that of poly(butylene 2,5-thiophenedicarboxylate) (PBTF). While also demonstrating good thermal stability. When the glycolic acid content was low, the copolyesters exhibited some crystallization capability, but they gradually became fully amorphous as the glycolic acid content increased. The tensile tests revealed that the young's modulus of the PBTFGA copolyesters ranged from 69.2 MPa to 221.4 MPa. With elongation at break exceeding 659%, outperforming most biodegradable packaging materials. Copolyesters exhibited excellent gas barrier properties to both oxygen (PO2 = 0.024 barrer) and carbon dioxide (PCO2 = 0.029 barrer), both of which are superior to poly(butylene 2,5-thiophenedicarboxylate). The incorporation of glycolic acid significantly reduced the crystalline content of the copolyesters, facilitating the interaction of water molecules with ester bonds in the polymer backbone. The weight of poly(butylene 2,5-thiophenedicarboxylate-co-glycolate) was decreased significantly during enzymatic hydrolysis, indicating excellent degradation performance

Polystyrene Chain Geometry Probed by Ion Mobility Mass Spectrometry and Molecular Dynamics Simulations.

Polystyrene (PS) is a thermoplastic polymer commonly used in various applications due to its bulk properties. Designing functional polystyrenes with well-defined structures for targeted applications is of significant interest due to the rigid and apolar nature of the polymer chain. Progress is hindered to date by the limitations of current analytical methods in defining the atomistic-level folding of the polymer chain. The integration of ion mobility spectrometry and molecular dynamics simulations is beneficial in addressing these challenges. However, data on gas-phase polystyrene ions are rarely reported in the literature. We herein investigate the gas phase structure of polystyrene ions with different end groups to establish how the nature and the rigidity of the monomer unit affect the charge stabilization. We find that, in contrast to polar polymers in which the charges are located deep in the ionic globules, the charges in the PS ions are rather located at the periphery of the polymer backbone, leading to singly and doubly charged PS ions adopting dense elliptic-shaped structures. Molecular dynamics (MD) simulations indicate that the folding of the PS rigid chain is controlled by phenyl ring interactions with the charge ultimately remaining excluded from the core of the globular ions, whereas the folding of polyether ions is initiated by the folding of the flexible polyether chain around the sodium ion that remains deeply enclosed in the core of the ions.

An effective strategy to enhance phosphoric acid retention and proton conductivity stability: Construction of proton transfer channels with starch rather than H3PO4

To enhance the phosphoric acid (PA) retention as well as maintain high proton conductivity of phosphoric acid doped proton exchange membranes at high temperature, we successfully design a series of phosphoric acid doped biobased composite membranes by incorporation of starch and graphene oxide (GO) into poly arylene ether ketones (PAEK). Proton transfer channels should be mainly built through dense hydrogen bonds formed from massive oxygen-containing groups of starch mainchain, which is confirmed by Molecular dynamics (MD) simulation, FT-IR and XRD analysis. The dense hydrogen-bond structure could construct fast proton transfer channels with extreme low doping level (0.00484 molH3PO4). The excellent PA retention properties with almost unchanged proton conductivity at high temperature (200 °C) for 600 min indicates that PA molecules are firmly fixed into membranes. Thus, in this study, we suggest a novel strategy for stablizing proton conductivity at high temperature and improving PA retention properties of PA doped membranes, which is building dense hydrogen-bond structure with low PA doping level.Based on the results in this study and the Grotthuss proton transfer mechanism, dense hydrogen-bonds from oxygen-containing groups in polymer backbones should be more stable than hydrogen-bonds from massive H3PO4 molecules with high acid doping levels to promote proton conduction.

Bulking up: the impact of polymer sterics on emulsion stability.

Encapsulation of hydrophobic active ingredients is critical for targeted drug delivery as water-insoluble drugs dominate the pharmaceutical marketplace. We previously demonstrated hexadecane-in-water emulsions stabilized with a pH-tunable polymer, poly(acrylic acid) (PAA), via a steric layer preventing particle aggregation. Using vibrational sum frequency scattering spectroscopy (VSFSS), here we probe the influence of steric hindrance on emulsion colloidal stability by tailoring the molecular weight of PAA and by adding an additional methyl group to the polymer backbone via poly(methacrylic acid) (PMAA) at pH 2, 4, and 6. At low polymer molecular weight (2 and 10 kDa), PAA adsorption is entropy driven and akin to surfactant-mediated stabilization. With 450 kDa PAA, the longer polymer chain emphasizes enthalpically favored polymer-oil interactions to initially coat the surface, and forms layers at increasing molecular weight (1000 and 4000 kDa). PMAA exhibits better oil-solubility than PAA at low concentrations but cannot accommodate the steric hindrance at higher concentrations leading to disorder. Finally, we connect our molecular-level understanding of PAA ordering with temperature-dependent dynamic light scattering experiments and observe that emulsions coated with PAA at pH 2 and 4 maintain colloidal stability from 0-90 °C, making PAA a promising polymer for hydrophobic drug delivery.

Exploring the Impact of Ring Mobility on the Macroscopic Properties of Doubly Threaded Slide-Ring Gel Networks.

The integration of mechanically interlocked molecules (MIMs) into polymeric materials has led to the development of mechanically interlocked polymers (MIPs). One class of MIPs that have gained attention in recent years are slide-ring gels (SRGs), which are generally accessed by crosslinking rings on a main-chain polyrotaxane. The mobility of the interlocked crosslinking moieties along the polymer backbone imparts enhanced properties onto these networks. An alternative synthetic approach to SRGs is to use a doubly threaded ring as the crosslinking moiety, yielding doubly threaded slide-ring gel networks (dt-SRGs). In this study, a photo-curable ligand-containing thread was used to assemble a series of metal-templated pseudo[3]rotaxane crosslinkers that allow access to polymer networks that contain doubly threaded interlocked rings. The physicochemical and mechanical properties of these dt-SRGs with varying size of the ring crosslinking moieties were investigated and compared to an entangled gel (EG) prepared by polymerizing the metal complex of the photo-curable ligand-containing thread, and a corresponding covalent gel (CG). Relative to the EG and CG, the dt-SRGs exhibit enhanced swelling behavior, viscoelastic properties, and stress relaxation characteristics. In addition, the macroscopic properties of dt-SRGs could be altered by "locking" ring mobility in the structure through remetalation, highlighting the impact of the mobility of the crosslinks.

Efficient adsorptive separation of Cu(II) from Ph by ZIF-8 constructed with sodium alginate polymer backbone

With the rapid development of industrialization, the removal of heavy metal ions and small organic molecules from wastewater has triggered a hot debate. ZIF-8 was grown on a sodium alginate backbone using an in situ growth technique, the core-shell P-SMG@ZIF-8 was synthesized. It was also characterized by FTIR, XRD, SEM, UV–Vis and XPS, and the optimal conditions and mechanism of adsorption were explored. At pH 2.0, a contact time of 200 min, and 298 K, removal of Cu(II) and Ph up to 80.2 %, 65.6 % by P-SMG@ZIF-8, adsorption behavior consistent with Langmuir model for pseudo-secondary rates, the saturated adsorption of Cu(II) and Ph could reach up to 83.5812 mg/g and 78.1779 mg/g, respectively. And the adsorbed P-SMG@ZIF-8 is easy to separate and reusable, which is a cost-effective and efficient natural product-based adsorption material.

Exploring the Impact of Ring Mobility on the Macroscopic Properties of Doubly Threaded Slide‐Ring Gel Networks

AbstractThe integration of mechanically interlocked molecules (MIMs) into polymeric materials has led to the development of mechanically interlocked polymers (MIPs). One class of MIPs that have gained attention in recent years are slide‐ring gels (SRGs), which are generally accessed by crosslinking rings on a main‐chain polyrotaxane. The mobility of the interlocked crosslinking moieties along the polymer backbone imparts enhanced properties onto these networks. An alternative synthetic approach to SRGs is to use a doubly threaded ring as the crosslinking moiety, yielding doubly threaded slide‐ring gel networks (dt‐SRGs). In this study, a photo‐curable ligand‐containing thread was used to assemble a series of metal‐templated pseudo[3]rotaxane crosslinkers that allow access to polymer networks that contain doubly threaded interlocked rings. The physicochemical and mechanical properties of these dt‐SRGs with varying size of the ring crosslinking moieties were investigated and compared to an entangled gel (EG) prepared by polymerizing the metal complex of the photo‐curable ligand‐containing thread, and a corresponding covalent gel (CG). Relative to the EG and CG, the dt‐SRGs exhibit enhanced swelling behavior, viscoelastic properties, and stress relaxation characteristics. In addition, the macroscopic properties of dt‐SRGs could be altered by “locking” ring mobility in the structure through remetalation, highlighting the impact of the mobility of the crosslinks.

Endocytosis-Inspired Zwitterionic Gel Tape for High-Efficient and Sustainable Underoil Adhesion.

Marine oil exploration is important yet greatly increases the risk of oil leakage, which will result in severe environment pollution and economic losses. It is an urgent need to develop effective underoil adhesives. However, realizing underoil adhesion is even harder than those underwater, due to the stubborn attachment of a highly viscous oil layer on target surface. Here, inspired by endocytosis, a tough gel tape composed of zwitterionic polymer network and zwitterionic surfactants is developed. The amphiphilic surfactants can form micelle to capture the oil droplets and transport them from the interface to gel via electrostatic attraction of polymer backbone, mimicking the endocytosis and achieving robust underoil adhesion. Benefiting from the oil-resistance of polymer backbone, the gel further realizes a combination of i) long-term adhesion with high durability, ii) repeated adhesion in oil, and iii) renewable adhesion efficiency after exhausted use. The tape exhibits an ultra-high adhesive toughness of 2446.86 J m-2 to stainless steel in silicone oil after 30 days' oil-exposure; such value of adhesive toughness surpasses many of those achieved in underwater adhesion and is greater than underoil adhesion performance of commercial tape. The strategy illustrated here will motivate the design of sustainable and efficient adhesives for wet environments.

High‐Performance n‐Type Organic Thermoelectrics with Exceptional Conductivity by Polymer‐Dopant Matching

AbstractAchieving high electrical conductivity (σ) and power factor (PF) simultaneously remains a significant challenge for n‐type organic themoelectrics (OTEs). Herein, we demonstrate the state‐of‐the‐art OTEs performance through blending a fused bithiophene imide dimer‐based polymer f‐BTI2g‐SVSCN and its selenophene‐substituted analogue f‐BSeI2g‐SVSCN with a julolidine‐functionalized benzimidazoline n‐dopant JLBI, vis‐à‐vis when blended with commercially available n‐dopants TAM and N‐DMBI. The advantages of introducing a more lipophilic julolidine group into the dopant structure of JLBI are evidenced by the enhanced OTEs performance that JLBI‐doped films show when compared to those doped with N‐DMBI or TAM. In fact, thanks to the enhanced intermolecular interactions and the lower‐lying LUMO level enabled by the increase of selenophene content in polymer backbone, JLBI‐doped films of f‐BSeI2g‐SVSCN exhibit a unprecedent σ of 206 S cm−1 and a PF of 114 μW m−1 K−2. Interestingly, σ can be further enhanced up to 326 S cm−1 by using TAM dopant as a consequence of its favorable diffusion behavior into densely packed crystalline domains. These values are the highest to date for solution‐processed molecularly n‐doped polymers, demonstrating the effectiveness of the polymer‐dopant matching approach carried out in this work.

FLIM nanoscopy resolves the structure and preferential adsorption in the co-nonsolvency of PNIPAM microgels in methanol-water

Polymer microgels are swollen macromolecular networks with a typical size of hundred of nanometers to several microns that show an extraordinary open and responsive architecture to different external stimuli, being therefore important candidates for nanobiotechnology and nanomedical applications such as biocatalysis, sensing and drug delivery. It is therefore crucial to understand the delicate balance of physical-chemical interactions between the polymer backbone and solvent molecules that to a high extent determine their responsivity.In particular, the co-nonsolvency effect of poly(N-isopropylacrylamide) in aqueous alcohols is highly discussed, and there is a disagreement between molecular dynamics (MD) simulations (from literature) of the preferential adsorption of alcohol on the polymer chains and the values obtained by several empirical methods that mostly probe the bulk solvent properties.It is our contention that the most efficacious method for addressing this problem requires a nanoscopic method that can be combined with spectroscopy and record fluorescence spectra and super-resolved fluorescence lifetime images of microgels labeled covalently with the solvatochromic dye Nile Red. By employing this approach, we could simultaneously resolve the structure of sub-micron size objects in the swollen and in the collapsed state and estimate the solvent composition inside of them in ▪–▪ mixtures for two very different polymer architectures. We found an outstanding agreement between the MD simulations and our results that estimate a co-solvent molar fraction excess of approximately 3 with a very flat profile in the lateral direction of the microgel.

High-Performance n-Type Organic Thermoelectrics with Exceptional Conductivity by Polymer-Dopant Matching.

Achieving high electrical conductivity (σ) and power factor (PF) simultaneously remains a significant challenge for n-type organic themoelectrics (OTEs). Herein, we demonstrate the state-of-the-art OTEs performance through blending a fused bithiophene imide dimer-based polymer f-BTI2g-SVSCN and its selenophene-substituted analogue f-BSeI2g-SVSCN with a julolidine-functionalized benzimidazoline n-dopant JLBI, vis-à-vis when blended with commercially available n-dopants TAM and N-DMBI. The advantages of introducing a more lipophilic julolidine group into the dopant structure of JLBI are evidenced by the enhanced OTEs performance that JLBI-doped films show when compared to those doped with N-DMBI or TAM. In fact, thanks to the enhanced intermolecular interactions and the lower-lying LUMO level enabled by the increase of selenophene content in polymer backbone, JLBI-doped films of f-BSeI2g-SVSCN exhibit a unprecedent σ of 206 S cm-1 and a PF of 114 μW m-1 K-2. Interestingly, σ can be further enhanced up to 326 S cm-1 by using TAM dopant as a consequence of its favorable diffusion behavior into densely packed crystalline domains. These values are the highest to date for solution-processed molecularly n-doped polymers, demonstrating the effectiveness of the polymer-dopant matching approach carried out in this work.

Boron-containing cross-linker assisted single-ion conducting polymer electrolytes for high-performance and dendrite-free Li-metal batteries

Nowadays, single-ion conducting polymer electrolytes for high efficiency, stable, safe and dendrite-free Li-metal batteries are in great need to protect lithium metal anode. In this work, a boron-containing single-ion polymer electrolyte (BSPE), prepared by the copolymerization of allyl diglycol carbonate (ADC), lithium bis((trifluoromethyl)sulfonyl)amide (LiTFSI), and diisopropyl allylboronate (DPAB). The weak coordination interaction between Li+ and polar carbonate enhances Li+ transport ability. Further, the boron-containing cross-linker fixes the counter anions on the polymer backbones, limiting the movement of the anions and promoting the rapid and uniform Li+ transference. The BSPE with 3 wt% DPAB exhibits higher Li+ transference number (t+ = 0.77) and better ionic conductivity (1.36 × 10−4 S cm−1 at 25 °C) compared with that without DPAB. The wider electrochemical window (5.6 V vs. Li+/Li), stable polarization and suppressed lithium dendrites during the plating/stripping cycle at a current density of 0.2 mAcm−2 for 600 h provide the metal-lithium batteries with better safety and higher efficiency. In addition, the initial discharge capacity of LiFePO4/BSPE/Li is 140.7 mAh g−1 with 95.2 % coulombic efficiency, and the capacity retention still remains 98.7 % after 200 cycles at 0.1C. The excellent performance endows the BSPE with the potential application in high-performance lithium metal batteries.

Side-chain-induced changes in aminated chitosan: Insights from molecular dynamics simulations

Chitosan is a functional polymer with diverse applications in biomedicine, agriculture, water treatment, and beyond. Via derivatization of pristine chitosan, its functionality can be tailored to desired applications, e.g. immobilization of biomolecules. Here, we performed molecular dynamics simulations of three aminated chitosan polymers, where one, two, and three long-distanced side chains have been incorporated. These polymers have been previously synthesized and their properties were investigated experimentally, however, the observed dependencies could not be fully explained on the molecular level. Here, we develop a computational protocol for the simulation of functionalized chitosan polymers and perform advanced analysis of their conformational states, intramolecular interactions, and water binding. We demonstrate that intra- and intermolecular forces, especially hydrogen bonds induced by polymer side chain modifications, modulate dihedral angle conformational states of the polymer backbone and interactions with water. We explain the role of the chemical composition of the functionalized chitosans in their tendency to collapse and reveal the key role of the protonation of the amino group near the polymer backbone on the reduction of polymer collapse. We demonstrate that specific binding of water molecules, especially the intermediate water, is more pronounced in the polymer exhibiting such an amino group.

Efficient and facile dual post-polymerization modification using acetoacetate-acrylate Michael addition

Post-polymerization modification (PPM) is a valuable strategy for achieving diversified functional polymers; nonetheless, the pursuit of achieving mild and efficient dual modification along the polymeric backbone remains as a challenge. In this work, the Michael addition reaction of acetoacetates and acrylates have been demonstrated as a robust PPM technique. The reversible addition-fragmentation chain transfer polymerization of commercially available 2-(acetoacetoxy)ethyl methacrylate provides a polymer scaffold with controlled molecular weight and acetoacetate groups. These pendant groups are capable of undergoing efficient double addition reactions with acrylates, leading to an increased density of functional moieties within the polymeric backbone. This PPM reaction exhibits unique advantages such as mild reaction conditions (at 40 °C), rapid kinetics (completion within 1 h), and high atom economy. Consequently, a series of polymers with tunable thermal stability, glass transition temperature, and hydrophilicity have been successfully synthesized. Applications have been demonstrated for both the synthesis of polymers exhibiting aggregation-induced luminescence and the preparation of luminescent materials with adjustable mechanical properties. This pioneering work unveils a robust post-polymerization modification technique, significantly advancing the synthesis of innovative functional polymers.

Near-Infrared Emissive Super Penetrating Conjugated Polymer Dots for Intratumoral Imaging in 3D Tumor Spheroid Models.

This study describes the formation of single-chain polymer dots (Pdots) via ultrasonic emulsification of nonionic donor-acceptor-donor type (D-A-D) alkoxy thiophene-benzobisthiadiazole-based conjugated polymers (Poly BT) with amphiphilic cetyltrimethylammonium bromide (CTAB). The methodology yields Pdots with a high cationic surface charge (+56.5mV ± 9.5) and average hydrodynamic radius of 12nm. Optical characterization reveals that these Pdots emit near-infrared (NIR) light at a maximum wavelength of 860nm owing to their conjugated polymer backbone consisting of D-A-D monomers. Both colloidal and optical properties of these Pdots make them promising fluorescence emissive probes for bioimaging applications. The significant advantage of positively charged Pdots is demonstrated in diffusion-limited mediums such as tissues, utilizing human epithelial breast adenocarcinoma, ATCC HTB-22 (MCF-7), human bone marrow neuroblastoma, ATCC CRL-2266 (SH-SY5Y), and rat adrenal gland pheochromocytoma, CRL-1721 (PC-12)tumor spheroid models. Fluorescence microscopy analysis of tumor spheroids from MCF-7, SH-SY5Y, and PC-12 cell lines reveals the intensity profile of Pdots, confirming extensive penetration into the central regions of the models. Moreover, a comparison with mitochondria staining dye reveals an overlap between the regions stained by Pdots and the dye in all three tumor spheroid models. These results suggest that single-chain D-A-D type Pdots, cationized via CTAB, exhibit long-range mean free path of penetration (≈1µm) in dense mediums and tumors.

Optimization of sPEEK/S-TiO2 nanocomposite membranes using response surface methodology for low-temperature fuel cell

Polyether-ether-ketone (PEEK), a speciality thermoplastic polymer is treated with concentrated sulfuric acid to introduce sulfonated repeating units in its backbone. Sulfonated polyether-ether-ketone (sPEEK) is then compounded with sulfonated titanium dioxide (S-TiO2) nanoparticles according to design of experiments (DoE). FT-IR spectra for sPEEK/S-TiO2 nanocomposite membranes show the strong presence of peaks at 3500 cm−1 and 1632 cm−1 wave number because of bending and stretching vibrations of OH-group confirm successful sulfonation of polyether-ether-ketone polymer. Insertion of -SO3H group in polymer backbone hinders the stereo regularity of polymer chains and leads to an amorphous structure as confirmed by X-ray diffraction and transmission electron microscopy of membranes. Thermogravimetric analysis shows that the thermal stability of sPEEK is much poor than its precursor PEEK due to the presence of easily degradable -SO3H groups. Analysis of variance (ANOVA) results show that factor wt.% of S-TiO2 is the most influencing among the factors. The proton conductivity and ion exchange capacity (IEC) increase with wt.% of S-TiO2. Proton conductivity of pristine sPEEK is 31.1 mS/cm which significantly increased to be 60.7 mS/cm for sPEEK/S-TiO2 (0.10 wt%) nanocomposite membrane. IEC, water uptake, and swelling ratio were observed to increase with the addition of S-TiO2 (wt.%) in the sPEEK matrix, reaching values of 62.6 mmol/g, 11.6 %, and 18.6 %, respectively.

Development of injectable microgel-based scaffolds via enzymatic cross-linking of hyaluronic acid-tyramine/gelatin-tyramine for potential bone tissue engineering

Currently, the healing of large bone defects relies on invasive surgeries and the transplantation of autologous bone. As a less invasive treatment option, the provision of microenvironments that promote the regeneration of defective bones holds great promise. Here, we developed hyaluronic acid (HA)/gelatin (Ge) microgel-based scaffolds to guide bone regeneration. To enable the formation of microgels by enzymatic cross-linking in the presence of horseradish peroxidase (HRP) and hydrogen peroxide (H2O2), we modified the polymers with tyramine (TA). Spectrophotometry and proton nuclear magnetic resonance (1H NMR) spectroscopy analysis confirmed successful tyramine substitution on polymer backbones. To enable the formation of microgels by a water-in-oil emulsion approach, the HRP and H2O2 concentrations were tuned to achieve the gelation in a few seconds. By varying the stirring speed from 600 to 1000 rpm, spherical microgels were produced with an average size of 116 ± 8.7 and 68 ± 4.7 μm, respectively. The results showed that microgels were injectable through needles and showed good biocompatibility with the cultured human osteosarcoma cell line (MG-63). HA/Ge-TA microgels served as a promising substrate for MG-63 cells since they improved the alkaline phosphatase activity and level of calcium deposition. In summary, the developed HA/Ge-TA microgels are promising injectable microgel-based scaffolds in bone tissue engineering.

Electronically Conductive Polymer Enhanced Solid-State Polymer Electrolytes for All-Solid-State Lithium Batteries

All-solid-state lithium batteries (ASSLBs) have gained enormous interest due to their potential high energy density, high performance, and inherent safety characteristics for advanced energy storage systems. Although solid-state ceramic (inorganic) electrolytes (SSCEs) have high ionic conductivity and high electrochemical stability, they experience some significant drawbacks, such as poor electrolyte/electrode interfacial properties and poor mechanical characteristics (brittle, fragile), which can hinder their adoption for commercialization. Typically, SSCE-based ASSLBs require high cell stack pressures exerted by heavy fixtures for regular operation, which can reduce the energy density of the overall battery packages. Polymer–SSCE composite electrolytes can provide inherently good interfacial contacts with the electrodes that do not require high cell stack pressures. In this study, we explore the feasibility of incorporating an electronically and ionically conducting polymer, polypyrrole (PPy), into a polymer backbone, polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP), to improve the ionic conductivity of the resultant polymer–SSCE composite electrolyte (SSPE). The electronically conductive polymer-incorporated composite electrolyte showed superior room temperature ionic conductivity and electrochemical performance compared to the baseline sample (without PPy). The PPy-incorporated polymer electrolyte demonstrated a high resilience to high temperature operation compared with the liquid-electrolyte counterpart. This performance advantage can potentially be employed in ASSLBs that operate at high temperatures. In our recent development efforts, SSPEs with optimal formulations showed room temperature ionic conductivity of 2.5 × 10−4 S/cm. The data also showed, consistently, that incorporating PPy into the polymer backbone helped boost the ionic conductivity with various SSPE formulations, consistent with the current study. Electrochemical performance of ASSLBs with the optimized SSPEs will be presented in a separate publication. The current exploratory study has shown the feasibility and benefits of the novel approach as a promising method for the research and development of next-generation solid composite electrolyte-based ASSLBs.

Solvation Chemistry Enables Eutectogels with Ultrahigh Autofluorescence, Toughness, and Adhesion under Extreme Environments

AbstractCompared to conventional gels, eutectogels encompassing deep eutectic solvents (DESs) circumvent the shortboards including poor temperature resistance, high cost, and undesired toxicity. However, existing eutectogels suffer weak intra‐ and interchain interactions, which culminates in vanishing autofluorescence, weak mechanic and feeble adhesion. Although myriad strategies have been proposed to boost the polymer/polymer interactions within gels, the processes are time‐consuming, which are not suitable for mass production or emergent deployment. Herein, to deal with it, a facile solvation chemistry is leveraged to build dynamic rigid network via incorporating active polymer backbones and DESs. Within these eutectogels, DESs play a magnet‐like role, and physically cluster polymer chains together via multiple noncovalent forces, thus intensifying polymer/polymer and DESs/polymer interactions. This solvation network bestows rare autofluorescence and unprecedentedly high strength, toughness, and adhesion among reported analogues, even in harsh conditions. Moreover, the mechanism of solvation chemistry is fully scrutinized for the first time. It is believed that this facile strategy can be easily expanded to the orchestrations of other soft materials.

Combining linear and cyclic sulfones as a strategy for elaborating more efficient high-dielectric polymer materials: A second case of dipolar glass copolymers

Motivated by the excellent features exhibited by sulfone functional groups in the development of high-dielectric polymer materials, this work assesses the combination of linear and cyclic sulfone structures through copolymerization to prepare novel polymer materials exhibiting high dielectric constants (ԑr'), low dissipative behavior, and improved thermal properties. Five new polymethacrylate-based copolymers with varying compositions were synthesized through reversible addition-fragmentation chain transfer (RAFT) polymerization. The correct structure and macromolecular nature of the devised materials were confirmed by infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (1H/13C NMR), and gel permeation chromatography (GPC), while their thermal properties were evaluated using thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC). All specimens exhibited adequate thermal properties for most capacitor applications in terms of onset degradation (Ti) and glass transition (Tg) temperatures. All materials degraded well above 250 °C, with increased Ti and Tg values depending on the final composition of the cyclic sulfone monomer in the material. The incorporation of cyclic sulfones not only increased the thermal robustness of the specimens but also raised their Tg values to as high as 189 °C, notably expanding the range of temperatures where these systems can operate without dissipative phenomena. More importantly, broadband dielectric spectroscopy (BDS) revealed that all samples exhibited dielectric properties notably superior to those of conventional polymer materials, with high ԑr' values between 6.0 and 8.9 (at 25 °C and 1 Hz) and low loss factors (Tan(δ) < 0.018). Overall, the present work successfully demonstrates the advantages of including cyclic structures with high dipole moments in polymeric backbones, offering a new strategy to enhance the thermal and dielectric properties of high-dielectric polymer materials.