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1.
A well‐defined amphiphilic block copolymer consisting of a hydrophobic block poly(methyl methacrylate) (PMMA) and a hydrophilic block poly[N,N–2‐(dimethylamino) ethyl methacrylate] (PDMAEMA) was synthesized by activator generated by the electron transfer for atom transfer radical polymerization method (AGET ATRP). Kinetics study revealed a linear increase in the graph concentration of PMMA‐b‐PDMAEMA with the reaction time, indicating that the polymer chain growth was consistent with a controlled process. The gel permeation chromatography results indicated that the block copolymer had a narrow molecular weight distribution (Mw/Mn = 1.42) under the optimal reaction conditions. Then, poly(vinylidene fluoride) (PVDF)/PMMA‐b‐PDMAEMA blend membranes were prepared via the standard immersion precipitation phase inversion process, using the block copolymer as additive to improve the hydrophilicity of the PVDF membrane. The presence and dispersion of PMMA‐b‐PDMAEMA clearly affected the morphology and improved the hydrophilicity of the as‐synthesized blend membranes as compared to the pristine PVDF membranes. By incorporating 15 wt % of the block copolymer, the water contact angle of the resulting blend membranes decreased from pure PVDF membrane 98° to 76°. The blend membranes showed good stability in the 20 d pure‐water experiment. The bovine serum albumin (BSA) absorption experiment revealed a substantial antifouling property of the blend membranes in comparison with the pristine PVDF membrane. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42080. 相似文献
2.
胆红素是一种内源性毒素,当人体肝脏系统受损或代谢受阻时,则在体内累积,引起高胆红素血症,其具有神经毒性,严重时甚至会危及生命。无机纳米材料作为胆红素吸附剂越来越受到关注,但也存在因团聚而吸附效率降低、因颗粒过小而容易泄漏的问题。以聚偏氟乙烯(PVDF)为基膜原料,掺杂纳米TiO2颗粒,DMAc为溶剂、PVP为致孔剂,通过干湿相转化法,制得TiO2/PVDF共混微滤膜。当铸膜液中PVDF浓度为10%(质量)、TiO2含量为1%(质量)、PVP含量为6%(质量)时,制备的TiO2/PVDF共混微滤膜的胆红素特异性吸附显著。电镜照片及EDX能谱发现,该膜内部及孔隙中均匀分布TiO2颗粒,颗粒无团聚现象。实验还考察了胆红素初始浓度、吸附时间、吸附温度、pH等吸附条件的影响。 相似文献
3.
Zhengdong Fei Songsong Ying Ping Fan Feng Chen Enamul Haque Mingqiang Zhong 《应用聚合物科学杂志》2020,137(24):49015
Ultra high molecular weight polyethylene (UHMWPE) filters are widely used in water treatment. In the present work, a facile crosslinking technique is first applied to a UHMWPE flat membrane as a model to realize long-lasting hydrophilicity and improved water treatment efficiency. In the presence of a crosslinker, N, N′-methylene bisacrylamide (MBA), 2-hydroxyethyl methacrylate (HEMA), a hydrophilic modifier, is soaked into the surface of UHMWPE particles by blending. Then, a crosslinking reaction occurs during the initial sintering stage. Finally, sintering is completed at high temperature and pressure. The FTIR and SEM results show that HEMA is successfully crosslinked on the UHMWPE particle surface. Compared to a pristine membrane, the crosslinked UHMWPE flat membrane presents a lower water contact angle and is more rapidly penetrated by water. As a result, the crosslinked membrane can realize pressureless filtration. Another meaningful result is that the water flux recovery rate (FRR) is extremely high both for BSA and sludge filtration tests. Also a parameter K of 1 was obtained to represent the efficiency of the membrane treatment of water under pressureless conditions. These findings demonstrate that the crosslinking strategy is an effective method for realizing long-lasting hydrophilicity and is very promising for UHMWPE filters and other engineering applications. 相似文献
4.
Li Dong Xiangdong Liu Zhengrong Xiong Dekun Sheng Changhong Lin Yan Zhou Yuming Yang 《应用聚合物科学杂志》2018,135(4)
Polydopamine (PDA) layers and particles self‐polymerized by dopamine have ultraviolet (UV) absorbing property besides versatility and adhesive ability. Herein, a facile strategy for preparing poly(vinylidene fluoride) (PVDF) membrane coated with a thick PDA layer was developed to decrease UV transmittance through the surface modification of PVDF membrane. The PVDF membrane was modified by PDA deposition after pretreated with KOH/alcohol and KMnO4/KOH solution. Furthermore, we investigated the effect of coating conditions such as concentration of dopamine and Tris–HCl buffer solution, coating time, and temperature on the performance of membranes. The characterization results indicated that it is more conductive for PDA deposition on the surface PVDF‐OH films than original PVDF films. Most importantly, UV transmittance of PVDF‐OH film modified in dopamine solution under optimum condition for one time can decrease to as low as 0.122% at 320 nm, which showed excellent UV‐shielding property. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45746. 相似文献
5.
Preparation,surface wetting properties,and protein adsorption resistance of well‐defined amphiphilic fluorinated diblock copolymers
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Novel well‐defined amphiphilic fluorinated diblock copolymers P(PEGMA‐co‐MMA)‐b‐PC6SMA were synthesized successfully by RAFT polymerization and characterized by FTIR, 1HNMR and GPC. For copolymer coatings, static contact angles, θ, with water (θwater ≥ 109.5°) and n‐hexadecane (θhexadecane ≥ 68.9°) pointed to the simultaneous hydrophobic and lipophobic characteristics of the copolymer surfaces. Dynamic contact angle measurements indirectly demonstrated that copolymer films underwent surface reconstruction upon contact with water, which results in a surface with surface coverage of polar PEG units. Moreover, the distinct nanoscale microphase segregation structures were proved by atomic force microscopy (AFM) images. Finally, using bovine serum albumin (BSA–FITC) as the model protein, copolymers exhibited excellent protein adsorption resistance. It is believed that the combination of surface reorganization and nanometer‐scale microphase segregation structure endows the excellent protein resistance for amphiphilic fluorinated copolymers. These results provide deeper insight of the effect of surface reconstruction and microphase segregation on the protein adsorption behaviors, and these amphiphilic fluoropolymers can expect to have potential applications as antifouling coatings in the field of marine and biomedical. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41167. 相似文献
6.
Zwitterionic‐polymer‐functionalized poly(vinyl alcohol‐co‐ethylene) nanofiber membrane for resistance to the adsorption of bacteria and protein
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Wenwen Wang Ying Lu Mengying Luo Qinghua Zhao Yuedan Wang Qiongzhen Liu Mufang Li Dong Wang 《应用聚合物科学杂志》2016,133(44)
A zwitterionic poly(vinyl alcohol‐co‐ethylene) (PVA‐co‐PE) nanofiber membrane for resistance to bacteria and protein adsorption was fabricated by the atom transfer radical polymerization of sulfobetaine methacrylate (SBMA). The PVA‐co‐PE nanofiber membrane was first surface‐activated by α‐bromoisobutyryl bromide, and then, zwitterionic SBMA was initiated to polymerize onto the surface of nanofiber membrane. The chemical structures of the functionalized PVA‐co‐PE nanofiber membranes were confirmed by attenuated total reflectance–Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy. The morphologies of the PVA‐co‐PE nanofiber membranes were characterized by scanning electron microscopy. The results show that the poly(sulfobetaine methacrylate) (PSBMA) was successfully grafted onto the PVA‐co‐PE nanofiber membrane, and the surface of the nanofiber membrane was more hydrophilic than that of the pristine membrane. Furthermore, the antibacterial adsorption properties and resistance to protein adsorption of the surface were investigated. This indicated that the PSBMA‐functionalized surface possessed good antibacterial adsorption activity and resistance to nonspecific protein adsorption. Therefore, this study afforded a convenient and promising method for preparing a new kind of soft and nonwoven dressing material with antibacterial adsorption and antifouling properties that has potential use in the medical field. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44169. 相似文献
7.
Dandan Chen Feng Gao Tianyu Liu Jian Kang Ruizhang Xu Ya Cao Ming Xiang 《应用聚合物科学杂志》2021,138(42):51256
Anti-fouling properties are tightly related to the surface properties of reverse osmosis (RO) membranes. In our study, fluorinated polyethyleneimine (FPEI) was synthesized by introducing perfluoroalkyl groups into a hydrophilic polyethyleneimine (PEI) matrix, and the heterogeneous wettability surface with hydrophilic and low-surface-energy properties was constructed by grafting FPEI on membrane surface via the carbodiimide-induced method. Verified by the result analysis of SEM, AFM, and zeta potentials measurements, the fluorinated RO membrane surface presented denser, smoother, and reduced negative charge. The surface free energy of RO membrane surface after grafting FPEI decreased from 45.5 to 38.7 mJ/m2. By using bovine serum albumin (BSA), humic acid (HA), and dodecyltrimethyl ammonium bromide (DTAB) as model foulants, the fluorinated RO membrane exhibits optimal fouling resistance and fouling release properties compared to pristine membrane and membrane modified by surface grafting hydrophilic PEI. Especially, the high recovery ratio (99%) and low total flux decline ratio (17.2%) were acquired during the filtration of BSA solution. These results manifested that the construction of a heterogeneous wettability surface can further improve the anti-fouling properties of RO membranes compared to a pure hydrophilic surface, and the corresponding anti-fouling mechanism was put forward. 相似文献
8.
An adsorbent for CO2 capture was prepared by the grafting of acrylonitrile (AN) onto viscose fibers (VFs); this was followed by amination with triethylene tetramine (TETA). The effects of the reaction conditions, such as the concentrations of the monomer, initiator, and nitric acid, on the grafting degree and grafting efficiency were studied. The adsorption performance of the adsorbent for CO2 was evaluated by fixed‐bed adsorption. The highest dynamic adsorption capacity of the adsorbent for CO2 was 4.35 mmol/g when the amine content of the adsorbent VF–AN–TETA reached 13.21 mmol/g. Compared with the polypropylene (PP)‐fiber‐based adsorbent (PP–AN–TETA), VF–AN–TETA with hydroxyl groups on the fibers facilitated the diffusion of CO2 and water and led to a higher CO2 adsorption capacity than that of PP–AN–TETA. The VF–AN–TETA adsorbent also showed good regeneration performance: its CO2 adsorption capacity could still retain almost the same capacity as the fresh adsorbent after 10 adsorption–desorption cycles. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 132, 42840. 相似文献
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10.
Effects of polyethyleneimine molecular weight and proportion on the membrane hydrophilization by codepositing with dopamine
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Mussel‐inspired chemistry has attracted widespread interest in the surface modification of polymer membranes. We have previously demonstrated a dopamine (DA) assisted codeposition process of polyethyleneimine onto polypropylene microfiltration membranes (PPMMs) for surface hydrophilization. In this work, we further investigate the effects of PEI molecular weight and DA/PEI mass ratio on the codeposition process and membrane performance. The results indicate that only low‐molecular‐weight PEI bring a distinct promotion in both surface wettability and water permeation flux for PPMMs. On the other hand, either excess DA or PEI is detrimental to the surface hydrophilicity of the studied membranes. The optimized PEI molecular weight is 600 Da and the corresponding mass ratio is 1:1 for the surface hydrophilization of PPMMs. These results are beneficial to understand those codeposition processes of dopamine with other polymers. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43792. 相似文献
11.
Meimei Li Jingde Li Mi Zhou Yupei Xian Yonggang Shui Mengqiang Wu Yongyi Yao 《应用聚合物科学杂志》2020,137(9):48416
This work provides a novel approach to improve not only water flux but also fouling resistance of Polyvinylidene fluoride (PVDF) membranes. PVDF/Poly(vinyl alcohol) (PVA)-blended nanofiber membranes were prepared via electrospinning method. The structure and performance of blended nanofiber membranes were characterized by scanning electron microscopy (SEM), atomic force microscope (AFM), attenuated total reflection-Fourier-transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), contact angle measurement, tensile mechanical measurement, and filtration experiments. These results indicate that PVA was uniformly blend in the PVDF matrix. This blended nanofiber membranes with the ridge-and-valley structure and bicontinuous phase exhibited the hydrophilic performance and super-wettability, which is reflected in a drop of water fully spread within 1.44 s. Filtration experiments showed that the blended nanofiber membranes have ultrahigh flux and low irreversible fouling ratio. In general, this work enhances the possibility of hydrophilic modification of hydrophobic PVDF membranes. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48416. 相似文献
12.
Xiangyang Lian Wanjun Liu Jianqiang Xie Qiang Shi Shaowei Yao Yuexin Guo Yufeng Zhang 《应用聚合物科学杂志》2020,137(47):49557
Thin film composite (TFC) reverse osmosis (RO) membranes with high permeability have been prepared by interfacial polymerization based on tailoring the polysulfone (PSf) substrate structure by in situ embedded poly(p-phenylene terephthamide) (PPTA) star-like rigid supports. The star-like rigid supports were observed by the polarizing optical microscopy (POM) and transmission electron microscope (TEM). The surface properties of the substrates were investigated by FTIR, the water contact angle (WCA), FESEM and AFM. The WCA was decreased from 88.5° to 72.3° with the PPTA increasing from 0% to 8%, and the surface roughness increased from 24.2, 25.1, 33.5 and 58.6 nm, respectively. Furthermore, numerous interconnect micro-structures were constructed in the substrate when the PPTA content was up to 8%. The pure water flux of 8% PPTA/92%PSf substrate was up to 377.0 L m−2 h−1 and the flux decline rate was lowest (64%) after compacted at 5.5 MPa for 30 min. Otherwise, increasing the PPTA contents in the substrate enhanced the roughness, encouraged nanosheet formation and improved the permeability of TFC RO membranes. The pure water flux of the TFC RO membranes increased from 36.32 to 58.42 L m−2 h−1, where the NaCl rejection was about 99.5% at 5.5 MPa. 相似文献
13.
The work deals with the selection of sulfonating agent and preparation of polymeric coating on membrane step by step. The surface modification of a commercial ultrafiltration polyethersulfone (PES) membrane was covalently attached to the poly(styrene-co-divinylbenzene-co-4-vinylbenzylchloride). The whole process was tracked step by step using analytical methods. Chlorosulfonic acid and trimethylsilyl chlorosulfonate were tested as sulfonating agents. Ion-exchange capacity (IEC), water content, specific resistance, and permselectivity were measured and scanning electron microscope analyzed the surface of the cation exchange membrane. The best results were achieved using 5 wt % chlorosulfonic acid as sulfonating agent. IEC reached values of up to 2.44 meq g−1 of dry matter, permselectivity of 93.6%, area resistances of 10.1 Ω cm2, and specific resistance around 299 Ω cm. The prepared cation exchange PES membrane with chlorosulfonic acid can be used in electrochemical processes, for example, in electrodialysis. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48826. 相似文献
14.
Preparation and characterization of a composite nanofiltration membrane from cyclen and trimesoyl chloride prepared by interfacial polymerization
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A novel nanofiltration (NF) membrane was prepared with cyclen and trimesoyl chloride by interfacial polymerization on a poly(ether sulfone) ultrafiltration membrane with a molecular weight cutoff of 50,000 Da. The effects of the reaction time, monomer concentration, and heat‐treatment temperature are discussed. The physicochemical properties and morphology of the prepared NF membrane were characterized by Fourier transform infrared spectroscopy–attenuated total reflectance, scanning electron microscopy, energy‐dispersive spectrometry, and atomic force microscopy. The NF performances were evaluated with solutions of Na2SO4, MgSO4, Mg(NO3)2, and NaCl. The salt‐rejection order of the prepared NF membrane was as follows: Na2SO4 > MgSO4 > Mg(NO3)2 > NaCl. The resulting rejection of Na2SO4 and PEG600 (polyethylene glycol with the average molecular weight of 600) were more than 90%, whereas that of NaCl was approximately 10%. After the addition of silica sol in the aqueous phase (silica sol concentration = 0.1% w/v), the salt rejection of the membrane changed slightly. However, the water flux was from 24.2 L·m?2·h?1 (25°C, 0.6 MPa) up to 38.9 L·m?2·h?1 (25°C, 0.6 MPa), and the resulting membrane exhibited excellent hydrophilicity. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42345. 相似文献
15.
Isabel Jesswein Sarah Uebele Alina Dieterich Silke Keller Thomas Hirth Thomas Schiestel 《应用聚合物科学杂志》2018,135(16)
Coating processes have become an important fabrication step in membrane production, either to form a separation layer on a porous substrate or to tune specific properties. The coating procedure depends to a large extent on the membrane properties which substantially impedes a prediction of the coating thickness. To give an insight into the coating properties of various hollow fiber membranes, a selection of membranes with different pore sizes was coated with aqueous poly(vinyl alcohol) solutions at various coating velocities. It was found that material properties and pore sizes of the membranes have great influence on coating thicknesses. An intrusion of coating material into the membrane structure was determined with increasing pore size. Pure intrusion without formation of a dense surface layer took place when using a membrane with a mean pore size of ca. 500 nm. Coating results were correlated with the theoretical LLD law and for some membranes the coating thickness can be predicted quite well by the LLD law and its enhancements. When a significant amount of coating material penetrated into the membrane structure the LLD law loses its validity. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46163. 相似文献
16.
《应用聚合物科学杂志》2018,135(12)
With polydopamine (PDA) acting as interlayer, combined with electrospinning technology and a silanization method, here a versatile method for fabricating a superhydrophobic PES/PDA/ODTS fibrous mat is reported. Scanning electron microscopy, attenuated total reflection Fourier transform infrared spectroscopy, and contact angle measurements were applied to characterize the morphologies and chemical composition changes of the prepared fibrous mats. Their separation ability for oil/water mixtures was measured by self‐made instruments. The results show that the fabricated PES/PDA/ODTS fibrous mat displays a water contact angle too large to be assessed by the ordinary amount of water applied in a conventional measurement. In other words, a water drop of less than 10 μL adheres to the syringe needle and leaves with it during the measurement. The prepared PES/PDA/ODTS fibrous mat also shows a threshold sliding angle no more than 2.5°. At the same time, this kind of material exhibits superoleophilicity for organic solvents, such as n‐hexane, gasoline, toluene, and chloroform. The experimental contact angles were also analyzed using the Cassie–Baxter model to gain insights into the fundamental microstructure–wetting property relationship. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45923. 相似文献
17.
The aim of this study was to develop the water flux and antifouling properties of a polyamide (PA) nanofiltration membrane. A nascent PA membrane was prepared with an interfacial polymerization technique and modified with 2,5‐diaminobenzene sulfonic acid (2,5‐DABSA) as a second modification. The effects of the 2,5‐DABSA monomer concentration and the modification time on the membrane performance were investigated. The chemical structure, morphology, roughness, hydrophilicity, molecular weight cutoff, and antifouling properties of the membranes were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, atomic force spectroscopy, contact angle measurement, poly(ethylene glycol) tracers, and cetyl trimethyl ammonium bromide filtration, respectively. The PA membrane with optimized performance was shown to have a greater than 44% higher water permeate flux with a change in the salt rejection in the order RNa2SO4 > RCaCl2 > RNaCl to RNa2SO4 > RNaCl > RCaCl2. The improvement of the hydrophilicity led to excellent antifouling properties in the new PA membranes and illustrated a promising and simple method for the fabrication of high‐performance PA membranes. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43583. 相似文献
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19.
In situ studies of bovine serum albumin adsorption onto functionalized polystyrene latices monitored with a quartz crystal microbalance technique
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Manel Beragoui Chadlia Aguir Mohamed Khalfaoui Eduardo Enciso Maria José Torralvo Laurent Duclaux Laurence Reinert Marylène Vayer Abdelmottaleb Ben Lamine 《应用聚合物科学杂志》2015,132(23)
The adsorbability of bovine serum albumin (BSA) onto poly(styrene‐co‐itaconic acid) (PS–IA), poly(styrene‐co‐hydroxyethyl methacrylate) (PS–HEMA), poly(styrene‐co‐acrylic acid) (PS–AA), and poly(styrene‐co‐methacrylic acid) (PS–MAA) latices were investigated with a quartz crystal microbalance. The amount adsorbed onto the functionalized latices, except for PS–MAA, was greater than that adsorbed onto polystyrene (PS) latex. To explain this result, two kinds of interaction forces were considered, hydrogen bonding and hydrophobic interactions, whereas electrostatic interaction was assumed to be small. When comparing the two extremes of hydrophobic interaction and hydrogen bonding, the latter was stronger. The corrected adsorption mass suggested that the BSA molecules were adsorbed onto the PS–MAA latex in a side‐on mode. However, in the case of the PS, PS–IA, PS–HEMA, and PS–AA latices, the BSA molecules were probably adsorbed in multiple layers. The presence of the BSA in the latex particle surface was verified by attenuated total reflectance/Fourier transform infrared spectroscopy and atomic force microscopy. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42055. 相似文献
20.
Breath figure templated semifluorinated block copolymers with tunable surface properties and binding capabilities
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Lauri Valtola Mikko Karesoja Heikki Tenhu Petri Ihalainen Jawad Sarfraz Jouko Peltonen Melina Malinen Arto Urtti Sami Hietala 《应用聚合物科学杂志》2015,132(1)
Patterning of functionalized polymeric surfaces enables the adjustment of their characteristics and use in novel applications. We prepared breath figure (BF) films from three semifluorinated diblock copolymers, which all are composed of a polystyrene block and a semifluorinated one to compare their surface properties. “Click” chemistry was employed to one of the polymers, containing a poly(pentafluorostyrene) block to incorporate hydrophilic sugar or carboxylic acid moieties. The structure of the polymer alters the obtained porous morphology of the films. Contact angle (CA) analyses of the BF films reveals that the surface porosity increases water CAs compared with solvent cast films, and, in the case of hydrophobic polymers, leads to significant increase in the CAs of dodecane. The hydrophobicity of the BF films is further amplified by the removal of the topmost layer which leads in some cases to superhydrophobic surfaces. BF films containing glucose units are hydrophilic exhibiting water CAs below 90°. These glycosylated porous surfaces are shown to bind lectin Con A‐FITC or can be labelled with isothiocyanate marker. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41225. 相似文献