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Silicon has garnered significant attention as a promising anode material for high‐energy density Li‐ion batteries. However, Si can be easily pulverized during cycling, which results in the loss of electrical contact and ultimately shortens battery lifetime. Therefore, the Si anode binder is developed to dissipate the enormous mechanical stress of the Si anode with enhanced mechanical properties. However, the interfacial stability between the Si anode binder and Cu current collector should also be improved. Here, a multifunctional thiourea polymer network (TUPN) is proposed as the Si anode binder. The TUPN binder provides the structural integrity of the Si anode with excellent tensile strength and resilience due to the epoxy‐amine and silanol‐epoxy covalent cross‐linking, while exhibiting high extensibility from the random coil chains with the hydrogen bonds of thiourea, oligoether, and isocyanurate moieties. Furthermore, the robust TUPN binder enhances the interfacial stability between the Si anode and current collector by forming a physical interaction. Finally, the facilitated Li‐ion transport and improved electrolyte wettability are realized due to the polar oligoether, thiourea, and isocyanurate moieties, respectively. The concept of this work is to highlight providing directions for the design of polymer binders for next‐generation batteries. [ABSTRACT FROM AUTHOR]

In this study, catalytic inverse vulcanization based on trialkyl amines (TAAs) is presented. With oleophilic alkyl chain moieties, low-cost organic TAAs promote time-efficient reactions as nucleophilic activators, even at a low-temperature of 110 °C. TAAs improve the reaction yield and thermal properties of products, and suppress toxic H2S gas generation. Besides, TAAs can be extracted from the product and recycled again, showing eco-friendly characteristics. This study broadens the application range of sulfur-rich copolymers by utilizing TAAs that can inverse vulcanize the elemental sulfur with various unreactive crosslinkers. [ABSTRACT FROM AUTHOR]

With intrinsic optical and dynamic properties of polysulfide chains, inverse vulcanized copolymers have demonstrated immense potential for infrared (IR) optical applications. However, preparing highly IR‐transparent sulfur‐rich copolymers without sacrificing their thermomechanical properties remains challenging. To overcome the trade‐off relationship between IR optical and thermomechanical properties, an in situ microphase separation strategy for the inverse vulcanization of elemental sulfur utilizing self‐crosslinkable 1,3,5‐trivinylbenzene (TVB) is presented. Even with 80 wt% sulfur content, the microphase‐separated TVB‐rich domain self‐reinforces the copolymer with a noteworthy modulus of ≈2.0 GPa and a high glass transition temperature (Tg) of 92.6 °C, while still exhibiting outstanding IR optical properties. This work is expected to provide insights into the fundamental structure–property relationships of sulfur‐rich copolymers and pave the way for various practical applications. [ABSTRACT FROM AUTHOR]

Vitrimers are attracting attention owing to their cross‐linked polymer architecture with reprocessability based on an associative covalent adaptable network (CAN). To expand their field of application, intensive research is being conducted to control the properties of vitrimers. Herein, the properties of vitrimers are tuned to render these materials extrudable and weldable. The engineered vitrimer is utilized as a functional "ink" for fused filament fabrication (FFF) 4D printing. The rheological properties of the vitrimers are adjusted by changing the chemical formulation without the use of special chemicals, additional reactions, or unique processes. Using the intrinsic cross‐linked architecture of the vitrimers, shape memory performance is demonstrated and used in 4D printing applications. A bond exchange reaction involving transesterification leads to the topological rearrangement of vitrimers, thus allowing them to be reprocessed, reshaped, recycled, and reprinted. In addition, heterogeneous materials in the form of an epoxy vitrimer and ester‐containing polylactic acid (PLA) are joined using direct interfacial welding. This study suggests a simple approach to customize the characteristics of vitrimers to confer special properties (shape memory) upon conventionally printed 3D objects, which could be used for soft robot fabrication, the assembly of materials, and multifunctional composites. [ABSTRACT FROM AUTHOR]

Vitrimers have shown advantages over conventional thermosets via capabilities of dynamic network rearrangement to endow repairability as well as recyclability. Based on such characteristics, vitrimers have been studied and have shown promises as a 3D printing ink material that can be recycled with the purpose of waste reduction. However, despite the brilliant approaches, there still remain limitations regarding requirement of new reagents for recycling the materials or reprintability issues. Here, a new class of a 4D printable vitrimer that is translated from a commercial poly(ε‐caprolactone) (PCL) resin is reported to exhibit self‐healability, weldability, reprocessability, as well as reprintability. Thus, formed 3D‐printed vitrimer products show superior heat resistance in comparison to commercial PCL prints, and can be repeatedly reprocessed or reprinted via filament extrusion and a handheld fused deposition modeling (FDM)‐based 3D printing method. Furthermore, incorporation of semicrystalline PCL renders capabilities of shape memory for 4D printing applications, and as far as it is known, such demonstration of FDM 3D‐printed shape memory vitrimers has not been realized yet. It is envisioned that this work can fuel advancement in 4D printing industries by suggesting a new material candidate with all‐rounded capabilities with minimized environmental challenges. [ABSTRACT FROM AUTHOR]

A simple way to control the gate dielectric properties of vinyl-addition polynorbornene copolymers bearing pendant vinyl groups (P(NB/VNB)) through thiol–ene click chemistry is reported. The optimized content ratio of tetra-thiol cross-linkers leads to the enhanced gate dielectric properties and performance of organic field-effect transistors. Also, this approach provides photo-patternability, low-temperature solution-processing, and air-processability. [ABSTRACT FROM AUTHOR]

Thermadapt shape memory polymers (SMPs), utilizing a variety of dynamic covalent bond exchange mechanisms, have been extensively studied in recent years but it is still challenging to address several constraints in terms of limited accuracy and complexity for constructing 3D shape memory structures. Here, an effective and facile preparation of thermadapt SMPs based on elemental sulfur‐derived poly(phenylene polysulfide) networks (PSNs) is presented. These SMPs possess intrinsic near‐infrared (NIR)‐induced photothermal conversion properties for spatiotemporal control of their plasticity and elasticity. The NIR‐controllable plasticity and elasticity of the PSNs enable versatile shape manipulation of 3D multi‐shape memory structures, including building block assembly, reconfiguration, shape fixing/recovery, and repair. [ABSTRACT FROM AUTHOR]

This study investigates a coating method for doping a single-walled carbon nanotube (SWCNT)/poly(3-hexylthiophene) (P3HT) hybrid film. In the hybrid film, P3HT chains were very highly doped by simple spin-coating of a FeCl3/nitromethane solution. Hybrid films doped by spin-coating exhibited power factors of 267 ± 38 µW m−1 K−2, which is an improvement over that of hybrid films doped by conventional immersion, 103 ± 24 µW m−1 K−2. The excellent thermoelectric performance is originated from the dramatically increased electrical conductivity by the sufficient doping of P3HT in the hybrid films. [ABSTRACT FROM AUTHOR]

The influence of processing conditions, such as ink concentration and coating method, on the thermoelectric properties of SWCNT/P3HT nanocomposite films was investigated systematically. Using simple wire-bar-coating, SWCNT/P3HT nanocomposite films with high thermoelectric performance could be obtained without additional P3HT doping. The wire-bar-coated SWCNT/P3HT nanocomposite films exhibited power factors of up to 105 μW m(-1) K(-2) at room temperature. The SWCNT bundles with diameters in the range of 6-23 nm formed an interconnected network in the wire-bar-coated nanocomposite films. Network formation in these nanocomposite films was expected to be strongly related to the development of electrical pathways due to inter-SWCNT bundle connections. This study suggests that the thermoelectric performance of SWCNT/P3HT nanocomposite films could be optimized by controlling their processing conditions and morphology.