SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Jianfei Xiao,Xiaofang Yuan,Tian C. Zhang,Like Ouyang,Shaojun Yuan
Heteroatomic doped porous carbon (HPCs) is a promising advanced material, showing great application potential in greenhouse gas capture. Here, in-situ N-doped porous carbon (NPC) was developed via a novel and readily scalable strategy − one-step solvent-free melt polycondensation assisted by organic potassium salts, followed by pyrolysis and activation. As both a template and an activator, the added C 6 H 5 K 3 O 7 played an important role to create abundant microporous structure. The as-fabricated NPC-650–0.5 showed a rich N content (6.11 at.%), abundant narrow micro-porosity (0.3437 cm 3 ·g −1 ), and a high surface area (1209.37 m 2 ·g −1 ) and delivered an excellent CO 2 static adsorption capacity (4.16 mmol·g −1 and 8.40 mmol·g −1 at 100 and 500 kPa), a fast adsorption kinetics (circa 98% of balance capacity in 12 min), moderate heat of adsorption (25 to 30 kJ/mol), high selectivity of CO 2 /N 2 , and outstanding uninterrupted recyclability. Both the narrow micropore volume and N-doping sites had strong effects on the CO 2 adsorption capacity, indicating a physical and chemical adsorption process with the mechanism being multi-layer adsorption by the micropore filling. This work highlights the great potential of the NPC-650–0.5 for capturing CO 2 and offers new insights into a green activator and a simple and easy-to-scale method for preparing HPCs.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2024
·
IF 4.1
Boang He,Yufeng Chen,Yuan Liang,Hai Wan,Wei Liu,Zhongtao Xu,Shihang Dong,Yuwei Chen,Peng Wei,Shuohan Huang,Yong He,Yanping Wang,Yumin Xia
In this study, a series of low dielectric liquid crystal polyarylates were designed and synthesized through the acetylation of hydroxyl-containing monomers followed by melt polycondensation with 4-hydroxybenzoic acid (HBA), 6-hydroxy-2-naphthoic acid (HNA), bisphenol A (BPA), bisphenol AF (BPAF), terephthalic acid (TA) acid and 2,3,5,6-tetrafluoroterephthalic acid (TFTA). The molar ratio of HBA to HNA was controlled at 7:3. The structures of the acetylated monomers and polyarylates were characterized using FTIR and NMR spectroscopy, while the elemental composition of the polyarylates was analysed via XPS. WAXD and POM analyses revealed that the prepared polyarylates exhibit a single crystalline form and are capable of forming liquid crystals. DSC and TGA analyses indicated that the incorporation of bisphenol-type monomers (BPA or BPAF) disrupted the regularity of the main chain, leading to a decrease in both the melting point and thermal stability. Finally, the incorporation of bulky monomers (BPA or BPAF) and fluorinated monomers (BPAF and TFTA) into polyarylates increases free volume and decreases polarization, leading to a significant reduction in the dielectric constant.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION
·
2022
·Vol. 37
·期 4
·753-759
·
IF 1.271
Cheng Zhengzai,Li Yi,Djouonkep Lesly Dasilva Wandji,Zeng Sheng,Wang Huan,Wang Linfeng,Cai Shuanpu,Liu Panpan,Hu Hai,Yang Yingao,Li Jiaqi,Qin Jisong,Gauthier Mario
A series of degradable polyesters was synthesized via melt polymerization of 3,6-dioxaoctane-1,8-dioic acid and five different diols, catalyzed by antimony trioxide (Sb 2 O 3 ). The polymers were characterized by FT-IR and 1 H NMR spectroscopy, gel permeation chromatography (GPC) and differential scanning calorimetry (DSC) analysis. The polydispersity index (PDI = M w / M n ) of the polyesters ranged from 1.55 to 1.99, the weight-average molecular weight ( M w ) from 1.8 × 10 4 to 3.2 × 10 4 Da, the melting point from 63 to 123 °C, and the highest decomposition temperature observed was 363 °C. The influence of the structure of the polymer chain on hydrolytic degradability was investigated with tests performed at three different values of pH. The findings obtained provide useful insight for the molecular design and the synthesis of degradable polyesters.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR MATERIALS AND ENGINEERING
·
2024
·
IF 4.2
Xiangyang Chen,Shun Gong,Biao Zhao,Kai Pan
Biobased thermoplastic polyamide elastomers (TPAEs) have received increasing attention in both academia and industry. Here, a series of semi-biobased long-chain TPAEs are successfully synthesized via one-step melt polymerization, employing polyamide 1210 (PA1210) and polyetheramines (PEAs) as hard and soft segments, respectively. The prepared TPAEs demonstrate excellent mechanical properties, energy dissipation capabilities, low density, good damping, high resilience, and low melting temperature. More interestingly, the properties of the TPAEs can be customized by adjusting the content and molecular weight of PEA. By varying the molecular weights of the PEAs, two different thermal behaviors can be observed in the prepared TPAEs. Specifically, PEA with low molecular weight has good compatibility with PA1210, leading to an increase in the conformation of the crystalline region and a significant decrease in melting temperature. Meanwhile, high molecular weight PEA causes strong phase separation with PA1210, leading to limited crystalline regions and inadequate physical cross-linking, further resulting in suboptimal mechanical properties. This work provides new insights into the design and preparation of PEA-type biobased long-chain TPAEs.
研究领域:
材料科学
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高分子化学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2017
·
IF 2.813
Wei Sun,Fei Xu,Weiguo Cheng,Jian Sun,Guoqing Ning,Suojiang Zhang
A series of quaternary ammonium ionic liquids (ILs) were synthesized and employed as catalysts for the production of poly(isosorbide carbonate) (PIC) from diphenyl carbonate and isosorbide via a melt polycondensation process. The relationship between the anions of the ILs and the catalytic activities was investigated, and the readily-prepared IL tetraethylammonium imidazolate (TEAI) was found to exhibit the highest catalytic activity. After optimizing the reaction conditions, a PIC with a weight-average molecular weight ( M w ) of 25600 g/mol was obtained, in conjunction with an isosorbide conversion of 92%. As a means of modifying the molecular flexibility and thermal properties of the PIC, poly(aliphatic diol-co-isosorbide carbonate)s (PAIC)s were successfully synthesized, again using TEAI, and polymers with M w values ranging from 29000 to 112000 g/mol were obtained. 13 C NMR analyses determined that the PAIC specimens had random microstructures, while differential scanning calorimetry demonstrated that each of the PAICs were amorphous and had glass transition temperatures ranging from 50 to 115 °C. Thermogravimetric analyses found T d-5% values ranging from 316 to 332 °C for these polymers. Based on these data, it is evident that the incorporation of linear or cyclohexane-based diol repeating units changed the thermal properties of the PIC.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
POLYMER JOURNAL
·
2021
·Vol. 54
·期 1
·47-55
·
IF 3.08
Jiao Danhua,Cai Xiaodong,Song Qun,Zhou Ruiqun,Peng Xiao,Bao Dongmei
A series of aliphatic poly(carbonate-co-ester)s (PBCFs) were successfully synthesized via melt polycondensation of 1,4-butanediol (BD) and dimethyl carbonate (DMC) in the presence of biobased fumaric acid (FA). The prepared unsaturated copolymers had weight-average molecular weights ( M w ) in the 4.98 × 10 4 to 8.82 × 10 4 g·mol −1 range and from 1.56 to 1.83 polydispersities. They all had random microstructures. The physical properties of the novel poly(carbonate-co-ester)s, such as melting temperature ( T m ) and melting enthalpy ( ∆H m ), varied widely depending on their composition. The stiff fumaric acid units in the poly(butylene carbonate) (PBC) chain caused an increase in the glass transition temperature ( T g ) and thermal stability. Furthermore, PBCF10 to PBCF20 (with fumaric acid unit content of <19%) contained PBC crystals, while the lattice structure of PBCF40 to PBCF80 (with fumaric acid unit content greater than 37%) was similar to that of the poly(butylene fumarate) (PBF) type. The mechanical properties and biodegradability of the copolymers were also studied.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Xinyi Gao,Jie Jiang,Junyao Shen,Shaoliang Lin,Ling Zhao,Zhenhao Xi
Biobased poly(isosorbide carbonate) (PIC) has received wide attention due to its excellent performance and biomass feedstocks. Herein, PICs were synthesized from isosorbide (ISB) and diphenyl carbonate (DPC) by melt polycondensation. Several alkali metal catalysts and a basic ionic liquid were screened to synthesize PICs with high conversions of DPC and high molar mass. The combination of LiCl and tetramethylammonium acetate ([TMA][Ac]) exhibited excellent catalytic performance and reduced the reactivity difference between endo-hydroxyl (endo-OH) and exo-hydroxyl (exo-OH) group of ISB. PIC with a high intrinsic viscosity of 0.55 dL/g and glass transition temperature of 171 °C was obtained with the total catalyst amount of 500 ppm (based on ISB). A possible transesterification mechanism referring to the synergetic effects of cation–anion interaction and hydrogen bonding was proposed based on the nuclear magnetic resonance analyses and density functional theory calculations. It is expected that these results can provide guidance for the industrial catalyst design of biobased PICs.
研究领域:
材料科学
·
化学工程
·
有机化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2020
·
IF 7.632
Zifeng Yang,Lei Liu,Hongzhe An,Chenhao Li,Zhencai Zhang,Wenjuan Fang,Fei Xu,Suojiang Zhang
Green synthesis of poly(isosorbide carbonate) (PIC) with remarkable properties is a huge challenge in industrial applications due to low molecular weight and harsh reaction conditions. We reported a novel pathway to synthesize high molecular weight PIC through melt polymerization of isosorbide (ISB) and dimethyl carbonate (DMC), which are derived from the biomass and CO2, respectively. The effects of metal ion-containing compound catalyst on chemical structures, terminal groups, and molecular weight of PIC in the process of melt polycondensation were studied. Compared with the best reported catalyst lithium acetylacetonate, the weight-average molecular weight (Mw) of PIC was increased by using our preferred catalyst sodium tert-butoxide from 46 500 to 55 100 with the ISB conversion up to 99.0%, and the reaction time was decreased from 12 h to only 2.5 h, as far as we know, which is the highest Mw value and the most efficient catalyst achieved by one-step method. According to the results of the experiment and simulation, we found that high catalytic performance was ascribed to the weak interaction energy of anion–cation of catalyst and the strong proton acceptance ability of the anion of the catalyst. Meanwhile, increasing the interaction energy of anion–cation of the catalyst could inhibit the occurrence of the methylation side reaction and interestingly the activated endohydroxyl groups of ISB were found to be more easily methylated. Finally, based on the captured and detected intermediates of the two-stages of the reaction, a possible mechanim for the synergetic effects of cation–anion through hydrogen bond formation was proposed.
研究领域:
材料科学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2021
·Vol. 28
·期 8
·1-9
·
IF 3.097
He Tingwei,Liu Tao,Huang Junyao,Wang Xueli,He Yong,Ma Bomou
In this work, a novel poly(ester amide)s (PEAs) was designed and synthesized from dimethyl terephthalate (DMT), 3-amino-1-propanol (AP) and adipic acid (AA). Firstly, the aromatic diol monomer (BHTT) was synthesized by DMT and AP, it was characterized by 1 H NMR, 13 C NMR, FT-IR and DSC, respectively. Then, the BHTT and AA were used to synthesize the semi-aromatic PEAs with alternating structure by melt polymerization. The effects of polymerization temperature and time on the crystallization, thermal stability and amide transesterification of PEAs were fully investigated. It was found that the prepared PEAs are semi-crystalline polymer with melting point around 154–165 °C and decomposition temperature around 377–392 °C. Most important, the chemical structure of PEAs synthesized under different conditions was explored by 1 H NMR, 13 C NMR and DEPT spectra, which confirms the occurrence of amide transesterification during the melt polymerization process.
研究领域:
高分子化学
·
材料科学
✓ 已验证
DOI
高影响因子
ADVANCED MATERIALS
·
2024
·Vol. 37
·期 3
·2410395
·
IF 27.4
Riming Sun,Shaoyu Chen,Qingyun He,Pinghui Yang,Xuan Gao,Mengyang Wu,Junbo Wang,Chongyu Zhong,Xiangru Zhao,Mubai Li,Qiushuang Tian,Yingguo Yang,Aifei Wang,Wei Huang,Renzhi Li,Tianshi Qin,Fangfang Wang
Despite the ongoing increase in the efficiency of perovskite solar cells, the stability issues of perovskite have been a significant hindrance to its commercialization. In response to this challenge, a stepwise melting-polymerizing molecule (SMPM) is designed as an additive into FAPbI 3 perovskite. SMPM undergoes a three-stage phase transition during the perovskite annealing process: initially melting from solid to liquid state, followed by overflowing grain boundaries, and finally self-polymerizing to form a hydrophobic grain-scale encapsulation in perovskite solar cells, providing protection against humidity-induced degradation. With this unique property, coupled with the advantages of improved crystallization, diminished non-radiative recombination, and energy level alignment, FAPbI 3 -based perovskite solar cells with a 25.21% (small-area) and 22.94% (1 cm 2 ) power conversion efficiency and over 2000 h T95% stability under 85% relative humidity is achieved. Furthermore, the SMPM-based perovskite solar cells without external encapsulations sustain impressive stability during underwater operation, in which the black FAPbI 3 phase is maintained and Pb-leakage is also effectively suppressed. Therefore, the SMPM strategy can offer a sustainable settlement in both stability and environmental issues for the commercialization of perovskite solar cells.
研究领域:
材料科学
·
能源技术
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF POLYMER ANALYSIS AND CHARACTERIZATION
·
2023
·
IF 1.9
Peng Wei,Zhiqiang Li,Yanan Zhang,Yumin Xia,Yanping Wang,Yimin Wang
Aromatic naphthalene thermotropic liquid crystal copolyesters (N-TLCP) have strong intermolecular forces and possess excellent comprehensive properties. In this study, the N-TLCP/MWCNT nanocomposites derived from 6-hydroxy-2-naphthoic acid (HNA), 2,6-naphthalene dicarboxylic acid (NDA), terephthalic acid (TA), 4,4′-dihydroxy biphenyl (BP) and carboxyl MWCNT were prepared via in situ “one-pot” melt polymerization method. The structure and properties of N-TLCP/MWCNT composites were fully analyzed. The interaction between MWCNT and TLCP matrix was confirmed by FTIR, XPS, Raman spectrum and rheometric measurements; and the strong interaction was observed for addition of a small amount of MWCNT (<0.5 wt%), which was attributed to the fact that the functional group COOH on the surface of MWCNTs enhances the dispersion state of the CNTs and molecular interaction through hydrogen bond/chemical covalent bonds. As a result, the glass transition temperature, melting temperature, thermal stability and mechanical properties of the N-TLCP/MWCNT composite was improved. However, more addition of MWCNT would tend to aggregate and impact the molecular weight and structure of the N-TLCP by the chemical reaction between its COOH group and OH group of the N-TLCP, which is not favor for improving the mechanical properties.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
DESIGNED MONOMERS AND POLYMERS
·
2015
·
IF 2.78
Guang-Zhen Mo,Yan-Cheng Wu,Zhi-Feng Hao,Qiao-Fang Luo,Xin-Yu Liang,Li-Tao Guan,Zhao-Yang Wang
Using aminomethyl benzimidazole (AMB) as a model of benzimidazole-type drugs, a potential biodegradable drug-loaded polymer poly(lactic acid-co-aminomethyl benzimidazole) (PLAAMB) is synthesized as designed via direct melt polycondensation starting from d,l-lactic acid (LA). When the molar feed ratio LA/AMB is 40/1, the optimal synthetic conditions, including catalyst type and dosage, polycondensation temperature, and copolymerization time are discussed. After the prepolymerization at 140 °C for 8 h, using 0.4 wt% stannous oxide (SnO) as the catalyst, the melt copolymerization at 160 °C for 6 h gives the copolymer with the biggest weight-average molecular weight (Mw) 5300 Da. The structure and properties of the copolymer are systematically characterized with Fourier transform infrared, 1H NMR, gel permeation chromatography, differential scanning calorimetry, and X-ray diffraction. And the investigations on the influences of different molar feed ratios on the properties of PLAAMB show that, the copolymer PLAAMB with the biggest Mw of 9400 Da can be obtained. After the drug model AMB as a monomer is introduced into polylactic acid during the condensation, the Tg of the obtained PLAAMB is lower than the Tg of homopolymer poly(d,l-lactic acid) (PDLLA). The Mw and crystallinity of PLAAMBs can meet the requirement of drug-loaded polymers in the drug delivery.
研究领域:
高分子化学
·
药物化学
·
生物材料学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）