Polymers
·
2018
·Vol. 10
·期 11
·1287
·
IF 2.935
Wenmeng Zhang,Shaoyun Chen,Dongyang Chen,Zhuoliang Ye
Sterically hindered (S)-1,1′-binaphthyl-2,2′-diol had been successfully copolymerized with 4,4′-sulfonyldiphenol and 4,4′-difluorobenzophenone to yield fibrous poly(arylene ether ketone)s (PAEKs) containing various amounts of binaphthyl unit, which was then selectively and efficiently sulfonated using ClSO3H to yield sulfonated poly(arylene ether ketone)s (SPAEKs) with ion exchange capacities (IECs) ranging from 1.40 to 1.89 mmol·g−1. The chemical structures of the polymers were confirmed by 2D1H–1H COSY NMR and FT-IR. The thermal properties, water uptake, swelling ratio, proton conductivity, oxidative stability and mechanical properties of SPAEKs were investigated in detail. It was found that the conjugated but non-coplanar structure of binaphthyl unit endorsed excellent solubility and film-forming capability to SPAEKs. The SPAEK-50 with an IEC of 1.89 mmol·g−1exhibited a proton conductivity of 102 mS·cm−1at 30 °C, much higher than that of the state-of-the-art Nafion N212 membrane and those of many previously reported aromatic analogs, which may be attributed to the likely large intrinsic free volume of SPAEKs created by the highly twisted chain structures and the desirable microscopic morphology. Along with the remarkable water affinity, thermal stabilities and mechanical properties, the SPAEKs were demonstrated to be promising proton exchange membrane (PEM) candidates for potential membrane separations.Keywords:proton exchange membranes;condensation polymerization;post-sulfonation;binaphthyl;film-forming capability
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials
·
2023
·Vol. 16
·期 9
·3296
·
IF 3.4
Wenqi Zou,Hongli Bian,Jinjing Guo,Jun Xu,Baohua Guo
Titanates are widely used in the synthesis of polyesters, such as Poly (butylene succinate) (PBS), due to their excellent catalytic activity for polycondensation. However, the hydrolysis sensitivity of titanate and side reactions at high temperatures restrict the further improvement of the molecular weight of polyesters and lead to the high content of end carboxyl group content in the products. In this work, we prepared titania–silica composite aerogels with resistance to hydrolysis and large specific surface area, which were further explored as an efficient catalyst for polycondensation reactions. A series of titania–silica composite aerogel catalysts for PBS polycondensation were successfully prepared by the sol-gel method. The influence of a Ti/Si ratio on the surface morphology and structure of the aerogels was examined. Titania–silica composite aerogel exhibits the surface characteristics of high specific surface area and high Lewis acid content. The specific surface area of titania–silica composite aerogels can reach 524.59 m2/g, and the Lewis acid content on the surface can reach 370.29 μmol/g. Furthermore, the catalytic performance for the polycondensation reaction of PBS was investigated. The intrinsic viscosity of PBS synthesized by catalysis with the composite catalyst with a Ti/Si ratio of 9/1 reaches 1.74 dL/g, with the Mnof 7.72 × 104g/mol. The hydrolysis resistance stability of the titania–silica composite aerogel is greatly improved compared with traditional tetrabutyl titanate (TBT), and the end carboxyl group content of PBS is effectively reduced to lower than 30 mol/ton.Keywords:Poly (butylene succinate);aerogel;catalysts;titanates;polycondensation
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Fengyuan Zhang,Jing Sun,Fei Liu,Junming Li,Ben-Lin Hu,Qingxin Tang,Run-Wei Li
With the increasing demand for elastic electronics, as a crucial component, elastic semiconductors have been widely studied. However, there are some issues for the current preparation of elastic semiconductors, such as harsh reaction conditions, low atomic economic utilization, and complicated product separation and purification. Aldehyde–amine polycondensation is an important chemical reaction with the advantages of mild reaction conditions, high atomic–economic efficiency, and easy separation and purification. Herein, intrinsically elastic semiconductors are developed via aldehyde–amine polycondensation, including a semiconducting segment and an elastic segment. The resulting polymer containing 42.62 wt % soft segments exhibits excellent stretchability and mechanical reversibility, especially with a lower modulus. Interestingly, the carrier mobility displays up to 0.04 cm2·V–1·s–1, in the range of the fully conjugated reference polymer (0.1 cm2·V–1·s–1). In brief, this strategy provides important guiding principles for the development of intrinsically elastic polymer semiconductors.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Molecular Catalysis
·
2022
·
IF 5.089
Ji Wang,Shuqing Zhang,Yiming Han,Lilei Zhang,Qingyin Wang,Gongying Wang,Xiaoming Zhang
PET (poly(ethylene terephthalate)) is one of the most important type of thermoplastic polyesters and widely used in various fields. Titanium-based catalysts are environmentally friendly and have higher catalytic activity than antimony-based catalysts when used in industry. However, titanium-based catalysts are prone to hydrolysis and result in discolored products. UiO-66 (Zr/Ti) with different Ti 4+ contents were successfully synthesized via one-step method. The material was characterized by XRD, SEM, FT-IR, XPS, BET and TG techniques. The results demonstrates that Ti 4+ was integrated into the UiO-66 framework. NH 3 - in situ DRIFTS, pyridine-IR, and NH 3 -TPD were used to explore the acidic properties of the samples, which proved that stable Lewis acidic sites are present in the samples even at 300 °C. The catalytic performance of UiO-66 (Zr/Ti) containing different Ti 4+ was explored under different conditions. At the same time, the scale-up experiment was carried out in a 5 L reactor, and the PET chips obtained had a lower b value. The catalytic reaction mechanism of UiO-66(Zr/Ti) was demonstrated by DFT calculations and the catalytic performance was close to Sb-based catalysts.
研究领域:
材料科学
·
化学工程
·
催化
✓ 已验证
DOI
高影响因子
Polymer Chemistry
·
2016
·Vol. 7
·期 25
·4176-4181
·
IF 5.687
Xiaodong Zhuang,Wuxue Zhao,Fan Zhang,Yu Cao,Feng Liu,Shuai Bi,Xinliang Feng
The synthesis of crystalline two-dimensional (2D) covalent organic frameworks (COFs) with fully unsaturated carbon–carbon backbones via a solution approach remains a great challenge. In this work, we report the first example of an olefin-linked 2D conjugated COF using a Knoevenagel polycondensation reaction of 1,4-phenylene diacetonitrile and three armed aromatic aldehyde. The resulting 2D poly(phenelyenevinylene) framework (2DPPV) possesses a sheet morphology, and a crystalline layered structure featuring a fully sp2-bonded carbon skeleton with pendant cyanide groups. Its unique alternating structure with a serrated configuration has been essentially evaluated using HR-TEM TEM analysis, nitrogen physisorption measurements, PXRD studies and theoretical simulations. Upon thermal and activation treatments, the as-prepared 2DPPV can be facilely converted into porous carbon nanosheets with large specific surface areas of up to 880 m2 g−1 which exhibit an excellent electrochemical performance as supercapacitor electrodes and electrocatalysts for the oxygen reduction reaction. This represents an economic non-template approach to 2D porous carbon materials for energy-related applications.
研究领域:
材料科学
·
能源科学
·
有机化学
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR RAPID COMMUNICATIONS
·
2025
·Vol. 46
·期 10
·2401044
·
IF 4.3
Hongxin Yao,Yongkang Zuo,Jikai Zhang,Hongjun Yang,Guangzhao Zhang
Aliphatic polycarbonate (APC) with long alkyl segments has received much attention for its biodegradability and biocompatibility. However, owing to its low molecular weight, it usually exhibits poor mechanical properties limiting its application. Here,a novel two-step condensation polymerization procedure by using an organic catalyst ( t -BuP 2 ) to synthesize high molecular weight APC is presented. The introduction of branching and hydrogen bonding in the polymerization would significantly improve its thermal and mechanical properties. The APC exhibits a melt temperature ≈80 °C, tensile strength of 17.7 ± 0.9 MPa, and impressive elongation at a break of 1136 ± 25%. This study provides a facile procedure to synthesize high-performance APC via condensation polymerization.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LANGMUIR
·
2024
·
IF 3.7
Chang Liu,Yang Hu,Lin Zhang,Wensheng Yang
Amino-functionalized silica has attracted a great deal of interest due to its high surface reactivity and potential for diverse applications across various fields. While the classical co-condensation method is commonly used to synthesize amino-functionalized silica particles, the mechanism of the reaction between (3-aminopropyl)triethoxysilane (APTES) and tetraethoxysilane under different conditions remains unclear, leading to unexpected self-nucleation or cross-linking between silica particles and consequently hindering rational control over the extent of functionalization. To address this issue, we systematically explored the co-condensation growth mechanism of amino-functionalized silica particles in the Stöber method by investigating the effects of APTES concentration and water content on the hydrolysis and condensation of silanes. The experimental results revealed that APTES could decrease the rate of hydrolysis/condensation, while the moderate water content promoted both the rate of hydrolysis/condensation and the overall quality of the silica particles. Consequently, we successfully demonstrated the rational synthesis of amino-functionalized silica particles with diameters ranging from 213 to 670 nm and a nitrogen content of ≤2.8 wt %. The relationship between the APTES concentration and particle properties exhibited a biphasic trend. At low APTES concentrations (≤2.0 mM), the particle size remained stable while the isoelectric point increased rapidly. Further increasing the APTES concentration from 2.0 to 100.0 mM induced a decrease in particle size due to APTES’s inhibitory effect on silica growth, with nitrogen content continuing to increase even after the isoelectric point remained unchanged. These silica particles, featuring varying surface amino group densities, were utilized as matrices for loading Au nanoparticles. The resulting functionalized particles exhibited distinctive catalytic ability in the reduction of 4-nitroaniline, demonstrating significant potential for applications across various fields.
研究领域:
材料科学
·
化学工程
·
催化领域
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Macromolecular Science Part A-Pure and Applied Chemistry
·
2024
·
IF 2.1
Liyang Wang,Menglu Yang,Fengwei Xia,Xin Cui,Yongjing Chu,Jianjun Yin,Zhicheng Qiu,Xin Li
Poly(ethylene glycol 1,4-cyclohexanedimethylene isosorbide terephthalate) (PEICT) copolymers synthesized from isosorbide (ISB), 1,4-cyclohexanedimethanol (CHDM), ethylene glycol (EG) and terephthalic acid (PTA) via polycondensation are a class of heat-resistant bio-based polyesters. The content of biomass-sourced ISB has an important influence on the various properties of the terpolymers but lacks detailed study. Herein, we synthesized a series of amorphous terpolyesters with different contents of ISB by melt polycondensation of ISB, CHDM, EG and PTA in a 30 L reactor, and investigated the effect of ISB content on the thermal, mechanical, optical and rheological properties. As the content of ISB increasing, the complex viscosities of terpolyesters were increased and the intrinsic viscosities were decreased. The tensile strength was increased from 45.1 MPa for poly(ethylene glycol 1,4-cyclohexanedimethylene terephthalate) (PCTG)to 48.1 MPa for PEI13.2CTandthe Tg was increased from 83.5 °C for PCTG (ISB 0 mol%) to 98.8 °C for PEI13.2CT (ISB 13.2 mol%). All the values of Td,5%, and Td,max of the terpolyesters were higher than 395 °C and 425 °C.
研究领域:
高分子科学
·
材料工程
·
化学合成
·
热分析
·
生物基材料
✓ 已验证
DOI
高影响因子
Polymer Chemistry
·
2018
·Vol. 9
·期 28
·3931-3943
·
IF 4.927
Yawei Sun,Qiuyan Wang,Shuying Zhang,Hao Li,Jinli Zhang,Daqing Li,Wei Li
A novel aromatic-doped polycaprolactone (Aro-PCL) material was synthesized through a facile PCL aminolysis-condensation polymerization incorporating the aromatic moiety to PCL chain and assessed by focusing on the dynamic aggregation and crystalline microdomains associated with the in vitro degradation properties, mechanical performance and biocompatibility. Characterizations by FTIR, NMR, UV-vis, DSC, WAXD, SAXS, POM, etc. illustrated that the incorporated aromatic and amine segments facilitated the formation of many low-oriented crystalline domains along the aliphatic chains. The results indicated that the evolution of mechanical performance is significantly associated with the chemical structure and the crystallization behavior of polymers. The Aro-PCL films possessed fast degradation rate, excellent biocompatibility and improved mechanical performance including augmented elongation at break, elastic modulus and radial strength. In particular, the Aro-PCL polymer films showed decrease in molecular weight at the beginning of hydrolytic degradation while maintaining mechanical support and stable mass. The Aro-PCL polymer has promising applications as a degradable biomaterial.
研究领域:
材料科学
·
高分子化学
·
生物医学工程
·
生物材料
✓ 已验证
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2025
·
IF 6.3
Yifei Ding,Wenxun Sun,Hongwei Gao,Ruiyu Zhang,Xiaobin Yang,Yongping Bai,Shuai Sun
High-transmittance polyester films are critical for advanced display technologies, yet the relationship between catalyst design and optical performance remains poorly understood. This work investigates seven metal-based catalysts and develops an economical and efficient composite catalyst accordingly. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies of these catalysts are calculated using density functional theory (DFT) method. Results demonstrate that catalysts with lower LUMO energy levels can significantly promote nucleophilic attack during polycondensation, consequently exhibiting superior catalytic efficiency. Subsequently, we prepare a composite catalyst composed of cobalt(II) acetate tetrahydrate and germanium(IV) oxide. By employing the composite catalyst, the synthesized PET films achieved promising transmittance of 91.43 % and luminosity of 92.82 %. This study provides a DFT-driven strategy for designing optical polyesters, offering a scalable approach for advanced display applications.
研究领域:
材料科学
·
化学工程
·
计算化学
·
高分子科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 44
·23191-23201
·
IF 3.708
Gang Zhang,Shu-shan Yuan,Zhi-min Li,Sheng-ru Long,Jie Yang
Two kinds of high glass temperature poly(arylene ether sulfone)s containing thioether and biphenyl units (PASSs) have been developed. The polymers were prepared by a polycondensation reaction of 4,4′-bis(4-chlorophenylsulfone)biphenyl (BCPSB) and 4,4′-dimercaptodiphenyl sulfone (DMDPS) (or 4,4′-bis(4-mercaptophenylsulfone)biphenyl (BMPSB)). They showed good thermal properties such as a relatively high glass transition temperature of 263–282 °C and a 5% weight-loss temperature (T5%) of 441–445 °C. The water flux and retention rate of the resultant membranes were 0.61–2.48 L m−2 h−1 and 89.47–94.91%, respectively. Interestingly, we found that the corrosion resistance of the membranes had been largely improved with the oxidization treatment. They were even insoluble in NMP, DMSO, concentrated H2SO4, aqua regia and so on, while the polymers without oxidation were soluble or destroyed in above solvents. In addition, we found the water flux of the oxidized membrane was also improved but the retention rate only decreased a little.
研究领域:
材料科学
·
高分子化学
·
膜技术
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR RAPID COMMUNICATIONS
·
2023
·Vol. 44
·期 24
·2300371
·
IF 4.6
Shikun Zhao,Shun Gong,Biao Zhao,Like Hou,Lurong Zhang,Qing Hu,Kai Pan
Polyamide 56 (PA56) has gained significant attention in the academic field due to its remarkable mechanical and thermal properties as a highly efficient and versatile biobased material. Its superior moisture absorption property also makes it a unique advantage in the realm of fiber textiles. However, despite extensive investigations on PA56's molecular and aggregate state structure, as well as processing modifications, little attention has been paid to its polymerization mechanism. Herein, the influence of temperature and time on PA56's polycondensation reaction is detailed studied by end-group titration and carbon nuclear magnetic resonance (NMR) techniques. The reaction kinetics equations for the pre-polymerization and vacuum melt-polymerization stages of PA56 are established, and possible side reactions during the polycondensation process are analyzed. By optimizing the reaction process based on kinetic characteristics, PA56 resin with superior comprehensive properties (melting temperature of 252.6 °C, degradation temperature of 371.6 °C, and tensile strength of 75 MPa) is obtained. The findings provide theoretical support for the industrial production of high-quality biobased PA56.
研究领域:
材料科学
·
化学工程
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）