Jiahui Su,Xiaoxuan Liu,Chengjing Xiong,Hong Huang,Yanyan Cui
In this study, we prepared a novel triblock copolymer, PDMS- b -(PMAEBB- co -PDMAEMA) 2 ( tri -PI) bearing side-chain benzophenone (BP) and coinitiator amine, as a macro-photoinitiator via reversible addition-fragmentation chain transfer (RAFT) copolymerization of the polymerizable photoinitiator 2-(methacryloyloxy)ethyl-2-benzoylbenzoate (MAEBB) and the unsaturated coinitiator amine 2-(dimethylamino)ethyl methacrylate (DMAEMA) with a bifunctional polydimethylsiloxane (PDMS) macro-chain transfer agent (macro-CTA). The structure of synthesized copolymer was confirmed by Fourier-transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance ( 1 H NMR), differential scanning calorimetry (DSC), and gel permeation chromatography (GPC). The effects of the photoinitiator/coinitiator ratio, concentration, and photoinitiator systems on the photopolymerization kinetics of tri(propylene glycol) diacrylate (TPGDA) were investigated by real-time FT-IR. The mobility of the tri -PI chain segments was proven by X-ray photoelectron spectroscopy (XPS), and the surface morphology of TPGDA curing coatings was studied by scanning electron microscopy (SEM). Results showed that tri-PI strongly suppressed the effect of oxygen inhibition on the photopolymerization system. Tri-PI was also used in the curing of UV-curable waterborne polyurethane acrylate (UV-WPUA) resin to determine its versatility.
Zhenyin Guo,Qingshan Yang,Songhan Wan,Kang Zhu,Hongtao Li,Chen Peng,Xianru He
Ethylene-vinyl acetate (EVM) rubber exhibits relatively poor elasticity, restricting its wide application. The effects of flexible vulcanization agents, ethylene glycol dimethacrylate (EGDMA) and tripropanediol diacrylate (TPGDA), on the mechanical properties and vulcanization characteristics of EVM were studied. At a 3 phr dosage, EGDMA and TPGDA increased elongation at break by 23.5% and 37.0%, respectively, while improving tension set recovery. These agents extended scorch time and reduced optimum vulcanization time. Vulcanization kinetics analysis demonstrated that these two agents shortened vulcanization time, improved production efficiency, and reduced initial reaction temperature (10°C–20°C) and activation energy (7–21 kJ/mol). This study offers a low-cost and simple method to enhance the elasticity and vulcanization properties of EVM and other rubber materials.
Solid-state lithium metal batteries (LMBs) using nonflammable solid electrolytes (SEs) are considered to be the new generation of energy storage devices with high energy density and good safety. However, many challenges, such as insufficient room-temperature ionic conductivity of SEs and tremendous electrode-electrolyte interfacial impedance, hinder the commercialization of solid-state LMBs. Here, we reported a novel composite solid electrolyte (CSE), consisting of a three-dimensional (3D) Li 6.25 Ga 0.25 La 3 Zr 2 O 12 (LLZO) nanoparticle-based framework and filled tripropylene gycol diacrylate (TPGDA)-based gel electrolytes, in which the gel electrolytes are prepared by in situ polymerization of the TPGDA monomer in the condition of liquid electrolyte . Owing to the high content of LLZO powder and PVDF binder, the nonflammable CSE shows superior thermal stability and outstanding mechanical property. Moreover, the CSE exhibits high room-temperature ionic conductivity (1.66 × 10 −3 S⋅cm −1 ) due to the large amount of liquid electrolyte loaded in the 3D framework. Besides, in-situ gel electrolytes facilitate the interfacial contact between electrolyte and lithium anode. Therefore, the LiFePO 4 /CSE/Li cell exhibits excellent cycling stability at room temperature , delivering a capacity retention ratio of 86.5% after 350 cycles at 1 C. This work can provide guidance in designing CSEs for high-performance lithium metal batteries.