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Totally found 2959 items.

  • [期刊] Effect of Polyether Sulfone Resin on Micromorphology, Thermal, Mechanical, and Dielectric Properties of Epoxy-Bismaleimide Composite Material
    In this study, 4,4'-diaminodiphenylmethane bismaleimide (BMI) was used as the matrix and epoxy resin (EP) and polyether sulfone (PES) were used as the toughening agent. PES/EP-BMI two-phase composites were prepared; they could be applied in more fields. The SEM results and energy spectrum analysis show a strong interaction between PES and EP-BMI molecules, and the surface of the two phases is fuzzy. PES dispersed uniformly in the EP-BMI matrix as the dispersed phase. The interface among phases is blurred and shows a mutual penetrating phenomenon. Furthermore, the cross-section of cracks is rough, and the directions change. This is a typical ductile fracture morphology. The highest bending strength and impact strength of PES/EP-BMI composite material are 144.9 MPa and 19.7 kJ/m(2), 41.2% and 90% increases copmared with those of EP-BMI matrix resin, respectively, when the content of PES is 4 wt%. Moreover, the decomposition temperature of the composite reaches 407 degrees C, 9 degrees C higher than that of EP-BMI. However, excess PES has a negative effect on the thermal decomposition temperature. The addition of PES increases the dielectric constant and dielectric loss of composites though they increase only slightly. The comprehensive properties of composites are at their best when the content of PES is 4 wt%. Overall, this study facilitates the applications of PES/EP-BMI composites in a broad range of fields.
  • [期刊] Polyether sulfone assisted shape construction of Calotropis gigantea fiber for preparing a sustainable and reusable oil sorbent
    Calotropis gigantea fiber (CGF) is obtained from the fruit of C. procera, and has waxy coating and large lumens. Owing to inherent hydrophobic-oleophilic property, CGF-based materials have been designed and developed into one kind of green oil sorbents. To facilitate its practical applications, polyether sulfone (PES) assisted shape construction of CGF was proposed here for preparing a sustainable and reusable oil sorbent by a facile phase inversion method. The resulting PES/CGF showed a stable sandwich structure, in which the fibers were spread evenly between two thin PES layers. By combining the advantages of PES and CGF, the resulting material can be not only processed into different shapes, but also has the potential to show high oil sorption towards to a variety of oils (including organic solvents). After a systematic optimization, PES/CGF exhibits superior oil-absorbing performance when compared with pure PES, with the sorption capacity of 4.26-9.24 g/g within a very short time. Besides, PES/CGF shows good oil/water selectivity and the changes in temperature can produce different effects on different oils. After ten cycles, PES/CGF has still higher oil-absorbing capacity, an indication of its good stability and excellent reusability. Therefore, PES/CGF has been found to be a sustainable, reusable, economical and environmentally friendly oil sorbent, and may show great potential for collecting oils in oily wastewater in the future.
  • [期刊] Characterization and optimization of laser sintering copolyamide/polyether sulfone hot-melt adhesive mixtures
    Purpose A new kind of polymer mixture (co-PA-PES) was prepared in different mass ratios, by mixing polyether sulfone hot-melt adhesive (PES-HmA) and copolyamide B249 (PA-B249). This study aims to investigate its characteristics of laser sintering and get the optimal process parameters. Design/methodology/approach The effect of mass ratio of co-PA-PES on thermal behavior was analyzed using a simultaneous thermal analyzer, and the density and mechanical properties of sintered parts were tested to evaluate the performance of the polymeric system. Scanning electron microscopy and Fourier transform infrared spectroscopy were performed to characterize the microstructure and binding mechanism of sintered co-PA-PES parts. Specifically, mechanical properties of the mixture with 20 Wt.% PA-B249 were optimized based on a design of experiment methodology, along with the restriction of maximum absorbable laser energy density. Findings Liquid phase fusion was considered as the main sintering mechanism for co-PA-PES, and mechanical interlocking was the dominant binding mechanism. The effects of mass ratios of this material on the thermal properties, density and mechanical properties were obtained via data results. Additionally, compared to neat PES-HmA, co-20 Wt.% PA-PES showed a 71.7 per cent increase in tensile strength, 24.4 per cent increase in flexural strength and 102.1per cent increase in impact strength. Originality/value This paper proposed a new kind of polymer mixture as the feedstock for laser sintering with the advantages of low price and easy processing. The filler of PA-B249 effectively improved the performance of the polymer mixture, including but not limited to mechanical properties.
  • [期刊] Characterization and optimization of laser sintering copolyamide/polyether sulfone hot-melt adhesive mixtures
    A new kind of polymer mixture (co-PA-PES) was prepared in different mass ratios, by mixing polyether sulfone hot-melt adhesive (PES-HmA) and copolyamide B249 (PA-B249). This study aims to investigate its characteristics of laser sintering and get the optimal process parameters.;;The effect of mass ratio of co-PA-PES on thermal behavior was analyzed using a simultaneous thermal analyzer, and the density and mechanical properties of sintered parts were tested to evaluate the performance of the polymeric system. Scanning electron microscopy and Fourier transform infrared spectroscopy were performed to characterize the microstructure and binding mechanism of sintered co-PA-PES parts. Specifically, mechanical properties of the mixture with 20 Wt.% PA-B249 were optimized based on a design of experiment methodology, along with the restriction of maximum absorbable laser energy density.;;Liquid phase fusion was considered as the main sintering mechanism for co-PA-PES, and mechanical interlocking was the dominant binding mechanism. The effects of mass ratios of this material on the thermal properties, density and mechanical properties were obtained via data results. Additionally, compared to neat PES-HmA, co-20 Wt.% PA-PES showed a 71.7 per cent increase in tensile strength, 24.4 per cent increase in flexural strength and 102.1per cent increase in impact strength.;;This paper proposed a new kind of polymer mixture as the feedstock for laser sintering with the advantages of low price and easy processing. The filler of PA-B249 effectively improved the performance of the polymer mixture, including but not limited to mechanical properties.
  • [期刊] Preparation and thermal properties of Alkoxy Silane functionalized polyether sulfone/well-defined poly(trimethoxysilyl) propyl methacrylate-based hybrid materials
    In this study, novel polyethersulfone (PES) and poly(trimethoxysilyl) propyl methacrylate (PMPS) containing hybrid materials were prepared. PES was functionalized with trimethoxysilane groups by UV-induced grafting reaction. PMPS was synthesized by atom transfer radical polymerization. In the followed process, the functionalized PES mixed with different amount of PMPS, thermally treated to promote sol-gel crosslinking process to prepare the PES-based hybrid materials. The trimethoxysilane grafted PES chains are covalently bonded with the well-defined trimethoxysilane groups of PMPS. The chemical structure of the prepared PES and PMPS is confirmed by Fourier transform infrared analysis. The morphology of the hybrids was investigated by scanning electron microscopy. The results of thermogravimetric analysis show that the thermal stability of the hybrid materials was significantly affected with the addition of PMPS. POLYM. ENG. SCI., 58:1346-1352, 2018. (c) 2017 Society of Plastics Engineers
  • [期刊] Graphitic-like carbon nitride improved thermal stability and photocatalytic antifouling performance of polyether sulfone membranes
    The poor thermal tolerance of organic membrane and membrane fouling are two of the main obstacles for wider application of membrane process. Adding inorganic compounds which own fascinating chemical property and thermal stability as the additives may be an effective method to alleviate the problems. In this study, different amount of graphitic carbon nitride (g-C3N4) were introduced into polyether sulfone (PES) membranes by the phase-inversion method. The impacts of the g-C3N4 addition on the structure, thermal stability, filtration property and photocatalysis of g-C3N4/PES nano composite membranes were systematically studied. The results illustrated that the g-C3N4 well dispersed into I'ES matrix without obvious aggregation. The g-C3N4 introduction slightly improved the hydrophilicity of the nano composite membrane and did not sacrifice the separation property. The thermal stability of g-C3N4/PES nano composite membranes was examined in terms of thermogravimetric analyses (TGA) and water flux recovery ratio (FRR) after which were heated treatment at different temperature (50-80 degrees C) for different times (30-240 s). The results revealed that the thermal stability and the filtration performance of PES membrane were significantly improved by the incorporation of g-C3N4 nanosheets. Also the addition of g-C3N4 nanosheets could endow the nanocomposite membranes with photocatalytic antifouling property.
  • [期刊] Influence of macromolecular additives on mechanical properties of polyether sulfone and polysulfone ultrafiltration membranes
    The influence of macromolecular additives on the mechanical properties of polyethersulfone (PES) and polysulfone (PS) is investigated. Ultrafiltration membrane sheets are prepared from PES and PSF based polymers via liquid non-solvent induced phase separation (NIPS), and employing polyvinylpyrrolidone (PVP), polyethylene glycol (PEG) and Pluronic (R) (PLU) co-polymers as macromolecular additives. The impact of additives on the main membranes' characteristics are studied; i.e., pure water permeability, membrane porosity, morphology and surface chemistry. The main mechanical properties are examined for all membranes and are correlated to the chemical composition of the membranes. Overall, the membranes prepared using PLU showed a superior tensile strength compared to other membrane samples, while PVP was found to enhance the membrane formation by suppressing microvoids formation. This study provides a better understanding of the main mechanical and other characteristics of membrane materials with regards to using additives.
  • [期刊] Influence of macromolecular additives on mechanical properties of polyether sulfone and polysulfone ultrafiltration membranes
    The influence of macromolecular additives on the mechanical properties of polyethersulfone (PES) and polysulfone (PS) is investigated. Ultrafiltration membrane sheets are prepared from PES and PSF based polymers via liquid non-solvent induced phase separation (NIPS), and employing polyvinylpyrrolidone (PVP), polyethylene glycol (PEG) and Pluronic (R) (PLU) co-polymers as macromolecular additives. The impact of additives on the main membranes' characteristics are studied; i.e., pure water permeability, membrane porosity, morphology and surface chemistry. The main mechanical properties are examined for all membranes and are correlated to the chemical composition of the membranes. Overall, the membranes prepared using PLU showed a superior tensile strength compared to other membrane samples, while PVP was found to enhance the membrane formation by suppressing microvoids formation. This study provides a better understanding of the main mechanical and other characteristics of membrane materials with regards to using additives.
  • [期刊] Surface modification of novel polyether sulfone amide (PESA) ultrafiltration membranes by grafting hydrophilic monomers
    In this study, new polymeric material namely polyether sulfone amide (PESA) containing hydrophile group was synthesized via polycondensation reaction of diamine with dicarboxylic acid. Synthesized PESA was used as main polymer to fabrication of novel PESA LW membranes to improve the membrane properties especially in view of fouling reduction. The PESA membrane was modified by grafting two hydrophilic monomers i.e. 3,5-diaminobenzoic acid (DBA) and gallic acid (GA) via interfacial polymerization. The prepared membranes were characterized by contact angle measurement, equilibrium water content (EWC), scanning electron microscopy (SEM), atomic force microscopy (AFM), FTIR-ATR analyses. Membrane performance was evaluated by measuring the pure water flux and humic acid (HA) solute separation with dead-end filtration system. As a result, the contact angle measurement showed that the PESA membrane had high hydrophilic surface. Also, super hydrophilic surfaces were introduced by grafting DBA and GA on the surface of PESA membrane. The SEM images proved the formation of large finger-likes in the sublayer for PESA membrane. Filtration tests showed that pure water flux and HA solution flux of the PESA rnembranes were higher in comparison to the PES membrane. Although fluxes were obviously decreased after grafting monomers onto the PESA membrane surface, higher HA separation efficiency was achieved. Meanwhile fouling tendency was decreased. All these results indicated that the new PESA modified membranes showed superior performance compared to the PES membrane. Furthermore, GA was found to be the most effective hydrophilic monomer to improve the membrane hydrophilicity and fouling resistibility. (C) 2015 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.
  • [期刊] 离子注入聚醚砜膜的光电特性研究
    用15keV的N+或Ar+注入聚醚砜(Polyether Sulfone简称PES)薄膜,在D=3×1016ions/cm2时,纯PES膜表面电导率提高了五个数量级,掺碘PES膜表面电导率提高了四个数量级。在D=3×1016ions/cm2时,离子注入PES膜的表面电导率已达到半导体水平且在大气中非常稳定。离子注入引起PES膜光吸收率显著增加。
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