SOLID STATE IONICS
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2018
·
IF 2.751
Mingzhao Xu,Mingyue Gang,Li Cao,Xueyi He,Yimeng Song,Zhongyi Jiang,Hong Wu,Yanlei Su
Anion-exchange membranes (AEM) are prepared from chloromethylated poly(ether ether ketone) (CMPEEK), which is quaternized by N , N , N ′, N ′-tetramethyl-1,4-phenylenediamine (TMPD) and 1-methylimidazole using a two-step method. TMPD can not only improve the mechanical properties but also provide more ion exchange groups and improve the availability of quaternary ammonium (QA) groups. By varying the amount of TMPD in the membrane casting solution , the comprehensive properties of the membranes are optimized and intensified. The anion conductivity is increased from 0.028 S cm −1 of the imidazolium functionalized poly (ether ether ketone) (ImPEEK) control membrane to 0.042 S cm −1 of the TMPD/ImPEEK membrane with a TMPD content of 5 wt%. Meanwhile, a 31.5% increase in ultimate tensile strength and a 27.8% increase in Young's modulus of the TMPD/ImPEEK membrane are achieved. This study exploited a facile approach to solving the trade-off relation between anion conductivity and mechanical properties.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
Polymers
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2017
·Vol. 9
·期 9
·305
·
IF 3.364
Jinggang Wang,Xiaoqing Liu,Jin Zhu,Yanhua Jiang
Bio-based polyesters derived from 2,5-furandicarboxylic acid (FDCA), including poly (ethylene 2,5-furandicarboxylate) (PEF), poly(propylene 2,5-furandicarboxylate) (PPF), and poly(butylene 2,5-furandicarboxylate) (PBF) have been synthesized and modified with 2,2,4,4-tetramethyl-1,3-cyclobutanediol (CBDO). Copolyesters with increased glass transition temperature, good barrier and better mechanical properties, as well as higher transparency were reported in this work. The chemical structures, composition, and sequence distribution of the copolyesters were determined by1H NMR and13C NMR. The degree of random (R) was close to 1 for all the copolyesters, indicating their random chemical structures. With the introduction of 10% CBDO units, the semi-crystalline PEF and PPF were changed into completely amorphous polyesters and the higher transparency was easily achieved. The glass transition temperature was increased from 87 °C for PEF to 91.1 °C for PETF-18, from 55.5 °C for PPF to 63.5 °C for PPTF-18, and from 39.0 °C for PBF to 43.5 °C for PBTF-18. The barrier properties investigation demonstrated that although the O2and CO2barrier of PEF/PPF/PBF were decreased by the addition of CBDO units, the modified copolyesters still showed good barrier properties.Keywords:2,5-Furandicarboxylic acid (FDCA);poly (ethylene 2,5-furandicarboxylate) (PEF);poly(propylene 2,5-furandicarboxylate) (PPF);poly(butylene 2,5-furandicarboxylate) (PBF);2,2,4,4-tetramethyl-1,3-cyclobutanediol (CBDO)
研究领域:
材料科学
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化学工程
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DOI
PubMed
高影响因子
ACS Applied Polymer Materials
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2022
·
IF 4.855
Yanru Chen,Linbo Wu,Bo-Geng Li
Poly(cyclohexane dimethylene-co-2,2,4,4-tetramethyl cyclobutylene terephthalate) (PCcBT) is a highly transparent, safe, and heat-resistant copolyester and has been commercialized to replace bisphenol A polycarbonate in many kinds of applications. However, there are still some shortcomings in its synthesis and processing such as 2,2,4,4-tetramethyl-1,3-cyclobutanediol (CBDO) sublimation, composition deviation, and relatively poor thermal stability. In this study, 2-methyl-1,3-propanediol (MPO) or 3-methyl-1,5-pentanediol (Pe′DO) were used as diol comonomers instead of cyclohexane dimethanol to synthesize poly(3-methyl-1,5-pentylene-co-2,2,4,4-tetramethyl cyclobutylene terephthalate) and poly(2-methyl-1,3-propylene-co-2,2,4,4-tetramethyl cyclobutylene terephthalate) (PMcBT) copolyesters. The effects of comonomers on solubility and sublimation of CBDO and the robustness of polymerization as well as thermal stability during polymerization and processing were examined with emphasis. The presence of Pe′DO and MPO facilitated CBDO dissolution and avoided CBDO sublimation and pipeline blocking, possibly due to a stronger intermolecular interaction between CBDO and Pe′DO or MPO. The deviations of composition and cis-trans ratio between the CBDO monomer and the copolymers were also reduced. The presence of a Pe′T or MT repeat unit endowed the copolymers with improved thermal stability, resulting in much less undesired melt foaming and volume expansion during melt polycondensation and processing. These copolymers are colorless, highly transparent, and heat-resistant materials with Tg up to 145 °C. Among them, PMcBT exhibits the best overall performance, displaying more balanced mechanical properties and better optical properties over commercialized PCcBT.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
高影响因子
POLYMER
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2024
·
IF 4.1
Liuchun Zheng,Xuedong Lv,Yongjun Zhang,Yi Liu
Due to the shortage of fossil resource and pollution problems caused by traditional non-degradable polymers, biodegradable polyesters attract increasing interest. Poly(butylene succinate) (PBS) has good biodegradation characteristics, relatively high melt temperature, excellent thermal stability and processing properties. However, its unique chemical structure renders it possesses relatively lower glass transition temperature ( T g ), insufficient mechanical properties. In this work, novel aliphatic cyclic rigid monomer (2,2,4,4-tetramethyl-1,3-cyclobutanediol (CBDO) was introduced into the macromolecular chain of PBS to improve the mechanical properties of PBS. The resulting copolyesters (PBCBS) show T g ranging from −34.7 to −25.6 °C. Tensile tests showed that theses polymers possess high tensile strength (44-29 MPa) and elongation at break as high as 450 %, which is prominently higher than that of commercial PBS and most biodegradable packaging materials. The novel copolyesters were studied by wide-angle X-ray diffraction analysis. It has been found that the introduction of CBDO reduces the crystallization ability of PBCBS and the main reason for this phenomenon is that the aliphatic ring restricts the mobility of macromolecular chains and regular stacking. As crystallinity is reduced, more water molecules can enter into the amorphous region, contact with the ester group bonds, and accelerate the degradation. In addition, the transparency at 700 nm for PBCBS can reach 95 % and it showed better solvent resistance as compared to polycarbonate. The biodegradable polyesters with satisfied combined performance were reported in this work.
研究领域:
材料科学
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生物降解材料
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高分子化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Bin Jiang,Tong Lei,Weida Chen,Meisi Chen,Chen Lu,Feng Zhang,Zhibing Zhang
Due to the proton transfer between aqueous solution of protic ionic liquids (PILs) and N,N,N’,N’-tetramethyl-1,6-hexanediamine (TMHDA), the liquid–liquid phases are gradually transformed into one phase during the absorption which is restored to two phases by carbon dioxide desorption, thus both the absorption and desorption processes were effectively intensified by phase conversion. The experimental results showed that CO 2 load of TPH (composed of TMHDA, PILs and H 2 O) was 45% higher than that of PILs-H 2 O, as well as an obvious increase of absorption rate. Moreover, the regeneration energy consumption of TPH was only 2.10 GJ/tonCO 2 . The spectral analysis and molecular dynamics simulations revealed that the proton transfer was the key of phased conversion, and it was regulated by the synergistic interaction between PILs and TMHDA during the CO 2 capture process. This kind of phase conversion strengthening absorbent with low viscosity is a useful way to achieve low energy carbon dioxide capture.
研究领域:
化学工程
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环境科学
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材料科学
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DOI
高影响因子
Journal of Materials Chemistry A
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2022
·Vol. 10
·期 25
·13286-13297
·
IF 14.511
Yaoguang Chen,Xiu Liu,Zhengqi Lao,Kang Yang,Fuzhen Li,Ling Chen,Kancheng Mai,Zishou Zhang
Inspired by the results of molecular dynamics simulation, a novel binary poly(ethylene-alt-2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) maleate) (PETM) and single-walled carbon nanotube (SWNT) nanocomposite thin film is first prepared and used as a flexible radical electrode. Benefiting from the enhanced affinity of PETM for SWNTs, a three-dimensional homogeneous co-continuous phase network structure is achieved in the PETM/SWNT electrode, which contributes to its high electrical conductivity, outstanding mechanical properties, and long-term deformation endurance. More importantly, the PETM/SWNT electrode exhibits a remarkable long-cycle life (96% capacity retention after 2000 cycles) and exceptional rate capability (almost unchanged capacity ranging from 5 to 50C). Additionally, a pouch cell based on the PETM/SWNT electrode demonstrated a stable operating voltage to power LED light strips under variant bending angles. These findings have practical significance towards designing high-performance flexible organic radical batteries.
研究领域:
材料科学
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能源技术
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产品关联
DOI
高影响因子
ENERGY & FUELS
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2025
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IF 5.3
Yinchun Liang,Hongyu Duan,Weida Chen,Lihui Sun,Feng Zhang
New absorbents combining the advantages of phase separation and easily regenerated products were prepared with 2-methyl-2-amino-1-propanol (AMP) as the main absorbent and tertiary amines as the auxiliary absorbents and phase splitters. The absorption performances of absorbents containing different tertiary amines were systematically compared. Among these tertiary amines, N,N,N′,N′-tetramethyl-1,3-propanediamine (TMPDA) exhibited the most effective properties. For the absorbent TMPDA–AMP–H2O system (TAH), an absorption load of approximately 2.6 mol/kg was achieved. The kinetic and thermodynamic properties of TAH absorption were evaluated. It was found that the absorption products were readily decomposed into HCO3–, and the regeneration efficiency of TAH was above 91% at 358 K, while the regeneration energy consumption was only 2.0 GJ/t CO2. It should be noted that the addition of TMPDA effectively inhibited the precipitation of bicarbonate, thus leading to a higher absorption capacity and lower energy consumption per ton of CO2 loaded.
研究领域:
化学工程
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环境科学
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材料科学
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能源技术
✓ 已验证
产品关联
DOI
高影响因子
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