POLYMER INTERNATIONAL
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2012
·Vol. 62
·期 10
·1457-1464
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IF 1.902
Youmei Bao,Jing He,Yuesheng Li
Hyperbranched polyesters with thioether linkages were facilely prepared from methyl 10-undecenoate, a castor oil-derived renewable chemical. The monomer was obtained in excellent yield through thiol–ene click chemistry in the presence of catalytic amounts of photoinitiator under UV irradiation. Subsequent bulk polycondensation via a transesterification process catalyzed by Ti(OBu) 4 , Sb 2 O 3 or Zn(OAc) 2 gave hyperbranched polyesters with high molecular weights and unusual crystalline properties. The degree of branching in the range 0.45 − 0.54 calculated from quantitative 13 C NMR spectroscopy and low inherent viscosities of 0.16 − 0.25 dL g −1 strongly confirmed the hyperbranched structures of the resultant polymers. © 2012 Society of Chemical Industry
研究领域:
材料化学
·
可再生资源化学
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高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2016
·
IF 5.557
Xin Kong,Yin Zhang,Si-Yi Zeng,Bao-Ku Zhu,Li-Ping Zhu,Li-Feng Fang,Hideto Matsuyama
To prepare thin film composite (TFC) nanofiltration (NF) membranes with improved flux and rejection performance at low pressure, hyperbranched polyester (HPE) was selected as the nano-sized macromonomer and successfully incorporated into the skin layers on PVC hollow fiber substrates via interfacial polymerization between trimesoyl chloride and the mixtures of hydroxyl-terminated HPE/piperazine (PIP). The resultant NF membranes were characterized using ATR-FTIR, FESEM , AFM and surface zeta potential , while their performance was evaluated in terms of permeate flux and rejection rates of different inorganic salts and neutral solutes. When the HPE content was lower than 60 wt% in HPE/PIP mixtures, the increased membrane surface roughness and the HPE embedded in skin layer effectively enhanced the permeate flux without sacrificing salt rejection for the prepared TFC NF membranes. Further increasing HPE content in HPE/PIP mixtures yielded looser polyamide skin layer, which led to the decline of solute rejection. Due to the larger size and good interfacial compatibility with cross-linked polyamide matrix, the incorporated HPE could exist stably in the skin layer. And thus, the prepared TFC NF membranes showed good flux and rejection stability in a long-term filtration process.
研究领域:
材料科学
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环境工程
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2024
·
IF 2.7
Yaomin Wang,Kaijuan Zou,Jun Wang,Jun Kang,Wenxia Yu,Huafeng Tian,Yuge Ouyang,Yujuan Jin,Rajesh Kumar,Xiaogang Luo
Polyvinyl alcohol (PVA) exhibits good water solubility, biocompatibility, and gas barrier properties. It is an important renewable and biodegradable polymeric material and is widely used in drug delivery, food packaging, tissue engineering, etc. However, its application is limited by insufficient mechanical performance. Hyperbranched polymers are a class of highly branched, structured macromolecular polymers with multiple branching sites and rich end functional groups. In this work, blend films were prepared by mixing PVA with water-soluble hyperbranched polyester (HBPE) using the solution casting method. The results showed that the hydroxyl groups of HBPE could form a hydrogen-bond-based cross-linking network with the hydroxyl groups of PVA. This, in turn, will effectively improve the mechanical properties, water absorption, thermal stability, etc. of the blend film. When the mass ratio of HBPE to PVA is 1:4, the elongation at break of the blend film was 404.23% with a tensile strength of 39.97 MPa. The prepared PVA/HBPE blend material is expected to be more widely applied in fields such as tissue engineering, packaging materials, etc.
研究领域:
材料科学
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生物医学工程
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高影响因子
REACTIVE & FUNCTIONAL POLYMERS
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2017
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IF 3.151
Ze-Lin Qiu,Xin Kong,Jia-Jia Yuan,Yu-Jie Shen,Bao-ku Zhu,Li-Ping Zhu,Zhi-Kan Yao,Chuyang Y. Tang
To prepare a new type of composite membrane with high flux and good dye removal performance, hyperbranched polyester (HPE) was selected as the reactive macromonomer and a cross-linked HPE skin layer was successfully formed on the PVC-UF membrane via one-step acteal reaction between HPE and glutaraldehyde (GA) from aqueous emulsion. The resultant membranes were characterized using ATR-FTIR, FESEM , surface zeta potential and CA, while the effects of GA concentration and heat treatment time on their performance were evaluated by permeate flux and rejection rate of sunset yellow (SY). The obtained HPE-M5 membrane exhibited a SY rejection rate of 96.4% and a permeate flux of 237.6 L m − 2 h − 1 at 0.4 MPa. Due to the good stability and the feasibility of backwashing treatment, the prepared composite hollow fiber membrane has a promising perspective of application in dye removal.
研究领域:
材料科学
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环境工程
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高影响因子
Electronic Materials Letters
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2015
·Vol. 11
·期 4
·702-706
·
IF 1.98
Han Wen-Song
In this manuscript, the third-generation hyperbranched polyester was synthesized with 2, 2-dimethylol propionic acid as AB 2 monomer and pentaerythrite as core molecule by using step by step polymerization process at first. Then, the Cu-Ag particles were prepared by co-reduction of silver nitrate and copper nitrate with ascorbic acid in the aqueous solution using hyperbranched polyester as template. Finally, the Cu-Ag@Ag particles were prepared by coating silver on the surface of Cu-Ag particles by reduction of silver nitrate. The synthesized hyperbranched polyester and Cu-Ag@Ag particles were characterized by Fourier transform infrared (FT-IR) spectroscopy, UV-vis spectra, x-ray diffraction, Laser light scattering, thermogravimetric analysis (TGA) and SEM. UV-vis spectra results showed that the Cu-Ag@Ag particles had a strong absorption band at around 420 nm. Laser light scattering and SEM studies confirmed that the most frequent particle sizes of Cu-Ag@Ag particles were 1.2 um. TGA results indicated that the Cu-Ag@Ag particles had good thermal stability.
研究领域:
材料科学
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化学工程
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高影响因子
PROGRESS IN ORGANIC COATINGS
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2025
·
IF 7.3
Dongchen Zheng,Qianyun Tan,Guangyu Zhu,Gege Zhang,Lixiang Yang,Zhongyi He,Tao Zhang,Fa-Qian Liu
Aiming at the problems of poor toughness, insufficient mechanical properties and bad long-term anticorrosion effect of epoxy resin coatings, a series of chemically cross-linked composite epoxy coatings were prepared in this work. The composite coating is formed by chemical bonding of aminated SiO 2 @TiO 2 particles, carboxylate-blocked hyperbranched polyester (HBPE-COOH) and TDI-modified E44 epoxy (TDI-E44). HBPE-COOH has a wealth of active sites and soft chain segments, which as an intermediate linker not only improves the bonding efficiency of the inorganic filler and the organic coating network, but also increases the flexibility of the composite coating. The adhesion strength of composite coating to the metal substrate is as high as 18.52 MPa, which ensures coating will not come off under seawater washing. The impact strength of the coating was 78 Kg·cm and no breakage occurred even when the coatings were curled on a 1 mm rod. The composite coating exhibits excellent corrosion resistance, and its impedance value remains above 1.0 × 10 9 Ω·cm 2 after 720 h of immersion in seawater, which is three orders of magnitude higher than that of the conventional epoxy resin. This high-density structure through chemical cross-linking makes epoxy resins as superior anti-corrosion coatings for marine applications.
研究领域:
材料科学
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化学工程
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高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2013
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IF 4.093
Xiuzhen Wei,Xin Kong,Jia Yang,Guoliang Zhang,Jinyuan Chen,Jiade Wang
Nanofiltration (NF) membranes have been prepared by interfacial polymerization of hyperbranched polyester with different number of terminated hydroxyl groups and trimesol chloride (TMC). Surface morphology and chemical structure of the different membranes were characterized by Fourier transforms infrared spectrometry (FTIR-ATR), scanning electron microscopy (SEM), atom force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). Molecular weight cut-off (MWCO) and surface zeta potential of the NF membranes were evaluated. The effect of pH value, operation pressure and salt concentration on rejection properties were also assessed. Nanofiltration properties were determined with organic anionic and cationic simulated dye wastewater. It was found that all NF membranes surface presented negative charge and had a MWCO of 4–6 kDa. Rejection properties of the NF membranes were affected by the dye charges, dye concentration and salt concentration.
研究领域:
材料科学
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环境工程
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高影响因子
EUROPEAN POLYMER JOURNAL
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2014
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IF 3.242
De Sun,Ping Yang,Hua-Long Sun,Bing-Bing Li
A novel composite membrane of cross-linked poly (vinyl alcohol)/hyperbranched polyester (PVA/HBPE) was prepared using glutaraldehyde (GA) as cross-linking agent for the dehydration of ethylene glycol/water (EG/water) mixtures. Hyperbranched polyester (HBPE) used in the preparation of PVA/HBPE membrane was synthesized through a pseudo one-step reaction of molten state 2,2-bis(hydroxymethyl)propionic acid (bis-MPA) and 1,1,1-trimethylol propane (TMP) using p-toluene sulfonic acid (p-TSA) as the catalyst. The branching degree of prepared HBPE was 0.4551 determined by 13 C NMR. FTIR, SEM, XRD, DSC, TGA, water contact angle and mechanical properties of PVA/HBPE membranes were measured to investigate the effects of HBPE on membrane structures and properties. PVA/HBPE membrane had a cross-linked structure and exhibited good thermal stability, good hydrophilicity and superior mechanical strength. When HBPE content was above 20 wt.%, HBPE particles formed on the surfaces of membranes and phase separation between PVA and HBPE occurred. With the increasing of HBPE content, feed water content and feed temperature, permeation flux increased significantly and separation factor decreased dramatically. The membrane containing 10 wt.% HBPE exhibited the best PV performance (water flux and separation factor were 43.77 g/(m 2 h) and 312 respectively for the 90 wt.% EG solution at 25 °C). The variation of permeation flux via feed temperature followed the Arrhenius relationship and the activation energy values were 12.83 and 39.29 kJ/mol for water and EG, respectively.
研究领域:
材料科学
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化学工程
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高影响因子
Energies
·
2023
·Vol. 16
·期 8
·3333
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IF 3.2
Derui Jin,Ji Mi,Yongsheng Guo,Yitong Dai,Wenjun Fang
It was found in our previous work that hyperbranched polyester (HPE) can generate radicals and accelerate the chemical reactions of hydrocarbon fuels used as initiators. In this work, the evaporation and autoignition characteristics of JP-10 droplets with or without HPE were investigated using the high-speed backlight imaging technique in detail. The results indicate that the puffing and micro-explosion phenomena of HPE-blended JP-10 droplets can accelerate fuel evaporation and autoignition. When a 0.1% mass concentration of HPE was used, the droplet lifetime was reduced by 16.5% in evaporation at 850 K and 18.0% in autoignition at 900 K. A mechanism of HPE that promotes puffing and micro-explosions was proposed by analyzing droplet images of combustion and SEM images of combustion residues. Overall, this study provides a method for improving the evaporation and autoignition performance of JP-10.
研究领域:
燃烧学
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化学工程
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航空动力学
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高影响因子
Journal of Coatings Technology and Research
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2020
·Vol. 18
·期 1
·259-269
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IF 1.815
Liu Jieming,Wang Shaoshun,Su Qiuping,He Jiajian,Li Yong,Xie Jing,Yi Guobin
A hyperbranched polyester with carboxyl end group (HPC) was synthesized by using trimellitic anhydride and neopentyl glycol as raw materials via A 2 + B 3 polycondensation. Then, waterborne hyperbranched polyester acrylate (WHPC) was synthesized by partially modifying the carboxylic groups of HPC with glycidyl methacrylate. In order to explore the influence of molecular weight, acrylate groups content, and ion groups content on performances, a series of WHPC films with different molecular weight, acrylate groups content, and ion groups content were prepared. The dynamic light scattering spectrometer analysis shows that the higher ionic groups content and the lower molecular weight cause the smaller particle size. The ionic group content has a positive effect on the solubility. The smaller molecular weight and particle size cause the lower viscosity. The Fourier-transform IR spectrophotometer reveals that the double bond final conversion increased with increasing acrylate groups content. The final conversion is between 69 and 86%. The curing speed is fast, and the curing time is about 70 s due to the numerous end groups owned by the hyperbranched structure. The dynamic mechanical thermal analysis coupled with end-use mechanical property tests illustrates that the crosslink density has a positive effect on the storage modulus and a negative effect on the flexibility. It is also found that glass transition temperature and pencil hardness are determined by the balance between crosslink segment and hyperbranched polyester segment. The thermogravimetric analysis proves that increased crosslink density and molecular weight promote the heat resistance of films. This work utilizes a novel hyperbranched structure that excels in viscosity, flexibility, and water solubility. Furthermore, the preparation process is convenient.
研究领域:
材料科学
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化学工程
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高影响因子
Journal of Coatings Technology and Research
·
2014
·Vol. 12
·期 2
·325-332
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IF 1.28
Xie Andong,Chen Hongxiang,Xu Caixia,Chen Hailun,Zhou Yu,Lin Yinli,Yang Minghua
Octahydroxyl-terminated and hexadecahydroxyl-terminated hyperbranched polyesters (HPE-8 and HPE-16) were synthesized from 2,2-dimethylol propionic acid and 1,4-butanediol. The hyperbranched waterborne polyurethane (HWPU) thickeners containing different branching structure and length of hydrophilic chain were prepared with hexamethylene diisocyanate, polyethylene glycol (PEG), cetyl alcohol, and HPE. The structures of HPE and HWPU were characterized by Fourier transform infrared spectra and nuclear magnetic resonance ( 1 H NMR and 13 C NMR). The rheological properties of polyurethane emulsion thickened by HWPU were measured using Brookfield LVDV-III rheometer, and the effects of HPE structure and PEG molecular weight on the thickening property of HWPU were studied. The results showed that HWPU with HPE branching number of 8 and PEG molecular weight of 4000 exhibited an excellent thickening effect in the aqueous polyurethane emulsion.
研究领域:
材料科学
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化学工程
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高影响因子
REACTIVE & FUNCTIONAL POLYMERS
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2024
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IF 4.5
Liang Qi,Ling-Xiao Hu,Zhi-Cheng Wang,Zhi-Gang Yuan,Hai-Lin Wen,Wen-Bin Liu,Jun Wang,Mehdi Derradji
In this study, a novel bio-based benzoxazine-terminated hyperbranched polyester (HB-Dfa) was designed and synthesized using renewable diphenolic acid and furfurylamine as raw materials through self-polymerization and Mannich condensation reaction . Meanwhile, the copolymers based on HB-Dfa and benzoxazine monomer (P-ddm) were prepared to investigate the effect of HB-Dfa on the properties of traditional benzoxazine. The chemical structure of HB-Dfa was elucidated by fourier transform infrared (FTIR) and nuclear magnetic resonance ( 1 H NMR) spectroscopies. The curing behavior and curing kinetics were investigated by differential scanning calorimetry (DSC), showing that it possessed a low temperature of exothermic peak and activation energy value compared with the P-ddm. Hence, the curing process of P-ddm was facilitated by the introduction of HB-Dfa. The thermomechanical and thermal properties of P-ddm/HB-Dfa copolymers were determined by dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA), respectively. Compared with the pure P-ddm resin, the introduction of HB-Dfa remained most of glass transition temperature ( T g ), cross-linking density and thermal stability, which could promote the curing reaction and reduce the curing temperature of the copolymers . In addition, HB-Dfa exhibited a low dielectric constant (2.46 ≥ k ≥ 2.16) and a low dielectric loss ( f ≤ 0.05) at frequencies range of 2–18 GHz, which could effectively modify the dielectric properties of the copolymer system.
研究领域:
材料科学
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化学工程
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高影响因子
危险品化学品经营许可证（带存储）