Thermal-induced Polymerization Research Articles

Integration of Porous High‐Loading Electrode and Gel Polymer Electrolyte for High‐Performance Quasi‐Solid‐State Battery

AbstractThe practical applications of lithium‐ion batteries (LIBs) are challenged by safety concerns using liquid electrolytes (LEs). The gel polymer electrolytes (GPEs) are considered as a promising candidate to solve this safety issue. In addition, using high‐mass loading electrodes is essential to achieve high energy density. However, poor interfacial contact between electrode and electrolyte remains a challenging issue, particularly for the high‐mass‐loading electrode. Here, porous channels are constructed in electrodes with high active material loading using the melamine formaldehyde sponge, and then the GPE is penetrated into porous channels of electrodes through an in‐situ thermal induced polymerization. The porous electrode structure with sufficient surface area improves electrolyte percolation and fast ion diffusion kinetics, which enables a uniform distribution of Li‐ion flux and effectively homogenizes the local current density to realize uniform Li deposition. The half cells and anode‐free full cells using the integration of porous electrodes and in‐situ polymerized GPEs exhibit excellent discharge capacity and cycle stability. This integration method is applicable for fabricating batteries with high energy density and safety.

Assembly and Thermal-Induced Polymerization of Histidine on Fumed Silica Surfaces

Assembly and Thermal-Induced Polymerization of Histidine on Fumed Silica Surfaces

Thermal Induced Polymerization of l‐Lysine forms Branched Particles with Blue Fluorescence

AbstractThe polycondensation of amino acids can originate complex polymers that display fascinating structural and optical properties. Thermally induced amidation of l‐lysine allows forming a branched polymer without the support of any catalyst. The polycondensation is completed at 240–250 °C; at higher temperatures, the amino acid degrades. The obtained polylysine particles have been studied by transmission electron microscopy (TEM), nuclear magnetic resonance, and infrared spectroscopy that allow for investigating the different steps of the synthesis. The resulting structure is characterized by peculiar optical properties, e.g., excitation‐dependent blue fluorescence and good quantum efficiency. Hydrogen bonds and the interactions of the amino acids are considered responsible for the optical properties of both l‐lysine monomer solutions at high concentrations and the branched nanopolymers.

Conformational rearrangement and polymerization behavior of frozen-stored gluten during thermal treatment

To elucidate the underlying mechanism of thermal-induced polymerization process of frozen-stored gluten, the conformational variations and polymerization behavior of fresh and frozen-stored gluten fractions during thermal treatment were comparatively tracked. The combined results of Raman spectra and fluorescence quenching by acrylamide suggested that frozen-stored gluten exhibited lower sensitivity to unfolding response upon heating, and more exposed tryptophan rather than tyrosine was detected for frozen-stored gluten when exceeding 70 °C, leading to the higher apparent binding constant for acrylamide and tryptophan than that of fresh gluten consequently. After the polymerization of glutenin and gliadin at 95 °C, the unstable trans-gauche-trans (t-g-t) conformation of disulfide bonds for frozen-stored gluten occupied more than 80%, while the stable gauche-gauche-gauche (g-g-g) diminished. The trans-gauche-gauche (t-g-g), t-g-t and g-g-g contents for the fresh gluten were similar, accounting for nearly 30%, respectively. Confocal laser scanning microscopy revealed the distorted glutenin network and heterogeneously distributed gliadin aggregates in frozen-stored gluten during thermal treatment. The polymerization ability of high molecular glutenin subunit Ax2, 1Dx5, Bx7.1 as well as the α- and γ-gliadin fractions in frozen-stored gluten were weakened compared with the fresh one.

Mimicking from Rose Petal to Lotus Leaf: Biomimetic Multiscale Hierarchical Particles with Tunable Water Adhesion.

Water-droplet adhesions of the coatings constructed by all-polymer multiscale hierarchical particles (MHPs) were finely adjusted within the range from highly adhesive to self-cleanable. The MHPs were synthesized via thermal-induced polymerization of the reactants absorbed into self-made hollow reactors and in situ capping of nanocomplexes onto the reactors' shell simultaneously. The dynamic wettability of the prepared MHPs was tuned between water-droplet sliding and water-droplet adhering by simply controlling the type of capped nanocomplexes. Water-adhesive force changed in the range from 31.28 to 89.34 μN. In addition, the raspberry-like particles (MHPs without nanocomplex capping) were used to construct superhydrophobic rose-petal-like surface with a high water-adhesive force, which can be applied in microdroplet transportation without loss. The MHPs with appropriate nanocomplex capping were used to fabricate superhydrophobic lotus-leaf-like fabric, exhibiting excellent antifouling property and superior mechanical stability. We believe that the prepared superhydrophobic MHPs with diverse water-adhesive forces are promising in potential academic research and industrial applications.

Thermal-induced polymerization shrinkage in silorane versus methacrylate based resin composite

Thermal-induced polymerization shrinkage in silorane versus methacrylate based resin composite

Continuous-Microflow Synthesis and Morphological Characterization of Multiscale Composite Materials Based on Polymer Microparticles and Inorganic Nanoparticles

This paper presents a new route to the synthesis of uniform and size-controlled inorganic/organic composite microparticles by means of microreaction technology. Au-nanoparticles in the range of 3 to 14 nm are synthesized by reduction of tetrachloroauric acid, while ZnO-nanoparticles (200–2000 nm) are synthesized in a continuous-flow two-step process using microtube arrangements for microsegmented flow. Both inorganic nanoparticles have a well-controlled size and narrow size distribution. Upon surface modification, the nanoparticles are then mixed on one hand with an acrylate-based monomer and, on the other hand, with an aqueous solution of acrylamide. Both solutions were then emulsified into uniform core-shell droplets by means of a capillary-based microfluidic device. Droplet's shell was hardened through UV-induced polymerization, whereas the core led to a hydrogel upon thermal-induced polymerization. Core-shell polymer microparticles (200–300 µm) with inorganic nanoparticles selectively incorporated int...

Synthesis and computational investigation of molecularly imprinted nanospheres for selective recognition of alpha-tocopherol succinate.

Molecularly imprinted polymers (MIPs) are macromolecular matrices that can mimic the functional properties of antibodies, receptors and enzymes while possessing higher durability. As such, these polymers are interesting materials for applications in biomimetic sensor, drug synthesis, drug delivery and separation. In this study, we prepared MIPs and molecularly imprinted nanospheres (MINs) as receptors with specific recognition properties toward tocopherol succinate (TPS) in comparison to tocopherol (TP) and tocopherol nicotinate (TPN). MIPs were synthesized using methacrylic acid (MAA) as functional monomer, ethylene glycol dimethacrylate (EGDMA) as crosslinking agent and dichloromethane or acetronitrile as porogenic solvent under thermal-induced polymerization condition. Results indicated that imprinted polymers of TPS-MIP, TP-MIP and TPN-MIP all bound specifically to their template molecules at 2 folds greater than the non-imprinted polymers. The calculated binding capacity of all MIP was approximately 2 mg per gram of polymer when using the optimal rebinding solvent EtOH:H2O (3:2, v/v). Furthermore, the MINs toward TPS and TP were prepared by precipitation polymerization that yielded particles that are 200-400 nm in size. The binding capacities of MINs to their templates were greater than that of the non-imprinted nanospheres when using the optimal rebinding solvent EtOH:H2O (4:1, v/v). Computer simulation was performed to provide mechanistic insights on the binding modalities of template-monomer complexes. In conclusion, we had successful prepared MIPs and MINs for binding specifically to TP and TPS. Such MIPs and MINs have great potential for industrial and medical applications, particularly for the selective separation of TP and TPS.

Synthesis of bulk and nanoporous carbon nitride polymers from ammonium thiocyanate for photocatalytic hydrogen evolution

Graphitic carbon nitride was synthesized by direct thermal polymerization of ammonium thiocyanate as the precursor. The transfer of this simple thermal-induced polymerization onto hard-templates with various nanoarchitectures enables the fabrication of nanostructured carbon nitridesvia a soft-chemical synthesis, while the involvement of a sulfur species within the reaction cascade offers additional chemical control of the texture and the electronic structures. The catalysts were subjected to several characterizations, and the results obtained revealed that nanoporous carbon nitrides can be obtained by templating with nanosized silica and SBA-15. Photocatalytic activity was evaluated toward hydrogen evolution from proton solution with visible light. Results show that g-C3N4 synthesized from ammonium thiocyanate exhibited improved photoactivity in comparison with g-C3N4 obtained from dicyandiamide. Further improvement in the activity was achieved by creating the nanostructures in g-C3N4. This is due to the enhanced surface area obtained which is favorable for light-harvesting and mass-transfer, as well as to the increased redox potential.

Construction and application of a stoichiometric displacement model for retention in chiral recognition of molecular imprinting

To do an extensive investigation of the chiral recognition mechanism of the molecular imprinting technique, two kinds of enantio-selective molecularly imprinted polymers (MIPs), N- tert-butoxycarbonyl- l-tryptophan ( N-Boc- l-Trp) and N- tert-butoxycarbonyl- l-tyramine ( N-Boc- l-Tyr), were synthesized by photo-induced and thermal-induced polymerization, respectively, and were employed as the stationary phase in liquid chromatography. A stoichiometric displacement model for retention (SDM-R) was successfully constructed and applied to evaluate the chiral separation of the MIPs. The simulation results showed that the values of ln k′ in the proposed SDM-R could be employed to characterize the efficiency of the MIP's total separation, and the value of n could be used to denote the space effect of the enantiomers interacting with the MIPs when the interaction between the solutes and MIPs was a hydrogen-bonding interaction. Further studies showed that the suitability of the MIP cavity structure mainly determined the chiral-recognition ability of the imprinting system, when a strong hydrogen-bond competitive solvent was added into the mobile phase.

Structural and magnetic characterization of α- and β-2,4-hexadiyne-1,6-diyl bis(2,2,5,5-tetramethyl-1-oxyl-3-pyrroline-3-carboxylate) and its thermal degradation product

Two polymorphs of the titled diradical have been characterized by X-ray diffraction, vibrational spectroscopies, and magnetic susceptibility; its radiation or thermal induced polymerization has not been achieved.