共查询到20条相似文献,搜索用时 250 毫秒
1.
Masoud Amirkhani Nicola Berger Mohamed Abdelmohsen Frank Zocholl Manuel Rodrigues Gonçalves Othmar Marti 《Journal of Polymer Science.Polymer Physics》2011,49(20):1430-1436
The Breath‐Figure technique was employed to imprint honeycomb structures in the polymer films via the condensation of water vapor on the surface of an evaporating polymer solution. Generally, the condensed water droplets can be stabilized by an end‐functional polymer or by particles added to the polymer solution. In this study, we carried out a systematic experiment on the effect of different stabilizers on the porous honeycomb structure under identical physical conditions. The end‐functional polymer produced a large area of regular spherical bubbles, whereas adding particles to the polymer solution leads to smaller arrays of the flattened bottom bubbles. The separation length between pores was larger for polymer/particle sample than that of the end‐functional polymer films. In the regular area of polymer/particle film many bubbles were not decorated by particles. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1430–1436, 2011 相似文献
2.
Eun Hee Min S. R. Simon Ting Laurent Billon Martina H. Stenzel 《Journal of polymer science. Part A, Polymer chemistry》2010,48(15):3440-3455
Stable and surface‐modified films with regular porous arrays were created by crosslinking honeycomb structured porous films prepared via breath figures from poly(styrene‐co‐maleic anhydride). The formation of open or closed pores of the films was controlled by the addition of a polyion complex. Subsequent crosslinking of the films with 1,8‐diaminooctane led to films, which maintain their structure in solvents. In addition, excess amino functionality after crosslinking allowed the attachment of RAFT agent, 3‐benzylsulfanyl thiocarbonyl sulfanylpropionic acid, for the controlled surface polymerization of N‐isopropyl acrylamide (NIPAAm) and N‐acryloyl glucosamine (AGA). The attachment of thermo‐responsive glycopolymers onto the honeycomb structured porous films was confirmed using contact angle measurements and confocal fluorescence microscopy. Cleavage of surface anchored polymers via aminolysis revealed that the molecular weights of the surface grafted chains are significantly larger than the molecular weight of the chains generated in solution. The honeycomb structured porous films with their grafted PNIPAAm‐ran‐PAGA polymer chains showed selective recognition of Concanavalin A (ConA). Below the lower critical solution temperature (LCST) of the surface, the conjugation is switched off, while above the LCST the surface grafted glucose moieties bind strongly to ConA. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 3440–3455, 2010 相似文献
3.
利用呼吸图案法制备聚(苯乙烯-b-丙烯腈)有序多孔薄膜 总被引:1,自引:0,他引:1
以自制的聚(苯乙烯-b-丙烯腈)(PS-b-PAN)嵌段共聚物为成膜材料, 采用呼吸图案法制备了有序多孔薄膜, 采用扫描电子显微镜(SEM)对薄膜形貌进行了分析, 研究了聚合物浓度、溶剂种类及共聚物结构对薄膜结构的影响. 结果表明, 薄膜表层为多孔结构, 且孔为圆形、以六方阵列形式排列; 薄膜表层下面是蜂窝状结构.以三氯甲烷(CHCl3)为溶剂时, 在较高浓度下制备的薄膜表层孔间距较大, 蜂窝结构尺寸较小, 且形成了多层结构. 与CHCl3为溶剂时相比, 挥发速度较快的二硫化碳(CS2)作溶剂时制备的多孔薄膜有序性较好, 薄膜表层孔径和孔间距均较大, 蜂窝结构尺寸较小. 以没有PAN链段的聚苯乙烯大分子引发剂(PS-Cl)为成膜材料时, 制备的薄膜表层没有形成多孔结构, 而是形成了窝状结构. 同时, 通过对薄膜表层晕的研究证明了多孔薄膜表层缺陷是由水滴处于液膜下较深的位置造成的. 相似文献
4.
5.
Fabrication of highly ordered porous membranes of cellulose triacetate on ice substrates using breath figure method 下载免费PDF全文
Bing Yu Hailin Cong Zejing Li Hua Yuan Qiaohong Peng Ming Chi Shujing Yang Ruixia Yang S. Ranil Wickramasinghe Jianguo Tang 《Journal of Polymer Science.Polymer Physics》2015,53(8):552-558
Highly ordered porous membranes of cellulose triacetate (CTA) were prepared successfully on ice substrates using breath figure method. The pore size and structure of the membrane were modulated by changing CTA concentrations and substrate materials. As the CTA concentration in the casting solution increased, the pore size in the formed membrane decreased. The regularity of the membrane cast on the ice substrate was much better than that of the membrane cast on glass substrate, because the low temperature of ice substrate slowed down the evaporation rate of organic solvent, which offered enough time for condensed water droplets to self‐organize into an ordered array dispersed in the polymer solution before their coagulation. The ordered porous CTA membrane was not only used for microfiltration, but also used for fabrication of functional microstructures. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 552–558 相似文献
6.
Polystyrene‐b‐poly(2,2,2‐trifluoroethyl acrylate)‐b‐polystyrene copolymers: Synthesis and fabrication of their hydrophobic porous films,spheres, and fibers 下载免费PDF全文
Chi Lv Kun Cui Shu‐Cai Li Hao‐Tian Wu Zhi Ma 《Journal of polymer science. Part A, Polymer chemistry》2016,54(5):678-685
New block copolymers Polystyrene‐b‐poly (2,2,2‐trifluoroethyl acrylate)‐b‐Polystyrene (PS‐PTFEA‐PS) with controlled molecular weight (Mn=5000‐11000 g?mol?1) and narrow molecular weight distribution (Mw/Mn=1.13‐1.17) were synthesized via RAFT polymerization. The molecular structure and component of PS‐PTFEA‐PS block copolymers were characterized through 1H NMR, 19F NMR, GPC, FT‐IR and elemental analysis. The porous films of such copolymers with average pore size of 0.80‐1.34 μm and good regularity were fabricated via a static breath‐figure (BF) process. The effects of solvent, temperature, and polymer concentration on the surface morphology of such film were investigated. In addition, microstructured spheres and fibers of such block copolymers were fabricated by electrospinning process and observed by scanning electron microscopy (SEM). Furthermore, the hydrophobicity of porous films, spheres, and fibers was investigated. The porous film showed a good hydrophobicity with the water‐droplet contact angles of 129°, and the fibers showed higher hydrophobicity with the water‐droplet contact angles of 142°. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 678–685 相似文献
7.
Hong Li Dr. Yi Jia Dr. Mingchun Du Dr. Jinbo Fei Dr. Jie Zhao Dr. Yue Cui Prof. Dr. Junbai Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(17):5306-5313
This study describes a facile breath‐figure method for the preparation of honeycomb‐like porous TiO2 films with an organometallic small‐molecule precursor. Multiple characterization techniques have been used to investigate the porous films and a mechanism for the formation process of porous TiO2 films through the breath‐figure method is proposed. The pore size of the TiO2 films could be modulated by varying the experimental parameters, such as the concentration of titanium n‐butoxide (TBT) solution, the content of cosolvent, and the air flow rate. In vitro cell‐culture experiments indicate that NIH 3T3 fibroblast cells seeded on the honeycomb‐like porous TiO2 films show good adhesion, spreading, and proliferation behaviors, which suggests that honeycomb‐like porous TiO2 films are an attractive biomaterial for surface modification of titanium and its alloys implants in tissue engineering to enhance their biocompatibility and bioactivity. 相似文献
8.
《Journal of Polymer Science.Polymer Physics》2018,56(17):1181-1192
Formylated polystyrene (PS‐CHO) was synthesized by chemical modification of polystyrene (PS) for the fabrication of honeycomb patterned (HCP) porous PS films with aldehyde group functionalized pores via breath figure method under humid conditions. The incorporation of hydrophilic aldehyde group affected the hydrophobicity of PS solution and assisted the self‐assembly of PS‐CHO toward pore. The presence of aldehyde groups in the films were proved by the post treatment with Tollens's reagent, which results in silver decoration at pores. The morphology of the films before and after silver decoration was studied by scanning electron microscopy analysis. The pore selectively self‐assembled aldehyde groups in the patterned porous films can have many applications as a reactive substrate in biomaterials and chemical moieties adhesion. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1181–1192 相似文献
9.
Composite ultrafiltration membranes with tunable properties based on a self‐assembling block copolymer/homopolymer system 下载免费PDF全文
Erik J. Vriezekolk Tibor Kudernac Wiebe M. de Vos Kitty Nijmeijer 《Journal of Polymer Science.Polymer Physics》2015,53(21):1546-1558
Composite ultrafiltration membranes were fabricated by coating a thin film of self‐assembling polystyrene‐block‐poly(ethylene oxide) (PS‐b‐PEO) block copolymers and poly(acrylic acid) homopolymers on top of a support membrane. Block copolymers self‐assembled into a nanostructure where the minority component forms cylinders, whereas homopolymers reside in the core of the cylinders. Selective removal of the homopolymers led to the formation of pores. The morphology of the polymer layer was controlled by varying the content of homopolymers or polymer concentration of the coating solution, which led to membranes with different molecular weight cutoffs (MWCOs) and permeabilities. Uniform pores were obtained using low homopolymer contents, whereas high homopolymer contents caused macrophase separation and resulted in large polydisperse pores or craters at the surface. The thickness of the block copolymer film also influenced the structure and performance of the membranes, where a thicker film results in a strong decrease in permeability but a lower MWCO. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1546–1558 相似文献
10.
Haotian Wu Tao Jiang Jun Zhu Kun Cui Qiaoling Zhao Zhi Ma 《Journal of polymer science. Part A, Polymer chemistry》2016,54(4):516-524
A series of new functional poly(ethylene‐co‐vinyl alcohol)‐g‐polystyrene graft copolymers (EVAL‐g‐PS) with controlled molecular weight (Mn = 38,000–94,000 g mol?1) and molecular weight distribution (Mw/Mn = 2.31–3.49) were synthesized via a grafting from methodology. The molecular structure and component of EVAL‐g‐PS graft copolymers were confirmed by the analysis of their 1H NMR spectra and GPC curves. The porous films of such copolymers were fabricated via a static breath‐figure (BF) process. The influencing factors on the morphology of such porous films, such as solvent, temperature, polymer concentration, and molecular weight of polymer were investigated. Ordered porous film and better regularity was fabricated through a static BF process using EVAL‐g‐PS solution in CHCl3. Scanning electron microscopy observation reveals that the EVAL‐g‐PS graft copolymer is an efficient compatibilizer for the blend system of low‐density polyethylene/polystyrene. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 516–524 相似文献
11.
Inverse opal films with unique optical properties have potential as photonic crystal materials and have stimulated wide interest in recent years. Herein, iridescent hybrid polystyrene/nanoparticle macroporous films have been prepared by using the breath‐figure method. The honeycomb‐patterned thin films were prepared by casting gold nanoparticle‐doped polystyrene solutions in chloroform at high relative humidity. Highly ordered hexagonal arrays of monodisperse pores with an average diameter of 880 nm are obtained. To account for the observed features, a microscopic phase separation of gold nanoparticles is proposed to occur in the breath‐figure formation. That is, individual gold nanoparticles adsorb at the solution/water interface and effectively stabilize condensed water droplets on the solution surface in a hexagonal array. Alternatively, at high nanoparticle concentrations the combination of breath‐figure formation and nanoparticle phase separation leads to hierarchical structures with spherical aggregates under a honeycomb monolayer. The films show large features in both the visible and NIR regions that are attributed to a combination of nanoparticle and ordered‐array absorptions. Organic ligand‐stabilized CdSe/CdS quantum dots or Fe3O4 nanoparticles may be loaded into the honeycomb structure to further modify the films. These results demonstrate new methods for the fabrication and functionalization of inverse opal films with potential applications in photonic and microelectronic materials. 相似文献
12.
Preparation of microporous polymers in the form of particles and a thin film from hyperbranched polyphenylenes 下载免费PDF全文
Min Chul Cha Yoonbin Lim Ji Young Chang 《Journal of polymer science. Part A, Polymer chemistry》2015,53(20):2336-2342
The use of a hyperbranched polymer as a building block for the synthesis of a microporous organic polymer was demonstrated. Hyperbranched polyphenylenes (HBPs) were prepared from (3,5‐dibromophenyl)boronic acid, which contained numerous unreacted bromophenyl end groups. Utilizing metal‐catalyzed coupling reactions between these functional groups, cross‐linked porous polymers were obtained. Although the HBPs did not show porosity, their cross‐linked polymers had highly porous structures with Brunauer–Emmett–Teller surface areas of up to 2030 m2/g. An insoluble porous thin film was fabricated by spin casting of a solution containing a HBP followed by Sonogashira cross‐coupling reaction. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2336–2342 相似文献
13.
Alberto S. de León Alexandra Muñoz‐Bonilla Marta Fernández‐García Juan Rodríguez‐Hernández 《Journal of polymer science. Part A, Polymer chemistry》2012,50(5):851-859
Polymeric films with porous structures and microsphere patterns were prepared by the method of breath figures, mixing poly(methyl methacrylate) (PMMA) and amphiphilic copolymers containing glucose moieties in their structure, glycopolymers. Statistical and block glycopolymers were used in a proportion of 10 wt %. The statistical glycopolymers were synthesized via conventional free radical copolymerization, whereas the block copolymer of methyl methacrylate and 2‐{[(D ‐glucosamin‐2‐Nyl) carbonyl]oxy}ethyl methacrylate, PMMA‐b‐PHEMAGl, was obtained by atom transfer radical polymerization. Glycopolymers were blended with a high molecular weight PMMA matrix and dissolved in a mixture of tetrahydrofuran and a small amount of water. Results showed that, depending on experimental conditions (water content, humidity, and type of copolymer), the observed final film morphology changes significantly. Thus, films with honeycomb pattern structures, spherical particles, or a mixture of both were obtained. In addition, polar glucose moieties were oriented principally either inside of the pores in the case of films and towards the surface in the case of particles. The specific surface bioactivity of these materials was examined using the specific lectin concanavalin A conjugated with fluorescein, Con A‐FITC. The successful binding of the Con A was demonstrated by fluorescence microscopy being more intense at the surface of the pores and of the particles. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
14.
The influence of casting parameters on the surface morphology of PS‐b‐P4VP honeycomb films 下载免费PDF全文
Ao Chen Idriss Blakey Andrew K. Whittaker Hui Peng 《Journal of polymer science. Part A, Polymer chemistry》2016,54(23):3721-3732
The “breath figures” method provides an efficient and cost‐effective method to produce highly ordered honeycomb patterns in polymeric films at micrometer and sub‐micrometer dimensions. The size and regularity of the pores can be adjusted through a series of physical and chemical parameters. In this study, amphiphilic diblock copolymers, polystyrene‐block‐poly(4‐vinyl pyridine) (PS‐b‐P4VP) with different lengths of P4VP, were synthesized through Reversible Addition‐Fragmentation Chain Transfer polymerization. The honeycomb‐patterned films were prepared from these well‐defined polymers through the dynamic breath figures method. A series of physical parameters including solution concentration, flow rate, humidity of the flow, and the humidity of the casting environment, were delicately adjusted to systematically investigate their effects on the morphology of the films. These studies identified four key factors which were found to influence the formation of the pattern. No obvious effect was found on the pore size by changing the length of P4VP block. The result provides clear direction on the fabrication of PS‐b‐P4VP honeycomb‐patterned films and more broadly contributes a deeper understanding of the processes involved in the formation of honeycomb patterns. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 3721–3732 相似文献
15.
综述了以Breath Figure(呼吸图案)法制备聚合物及纳米颗粒蜂窝状多孔结构的研究现状.当潮湿的气流吹到聚合物或纳米颗粒的有机溶液表面时,溶剂蒸发导致水微滴在液体表面冷凝重排成六角阵列结构.溶剂和水微滴蒸发完毕后,聚合物或纳米颗粒在基底上形成具有六角阵列的蜂窝状多孔结构.该技术是自组装领域的一大进展,在生物技术、组织工程、微图像技术、高端分离技术、光催化及医药等领域有望获得重要应用.本文系统阐述了规整蜂窝状孔结构材料的构建方法、构建材料、形成机理以及影响因素(包括湿度、浓度、气流方向和速度、溶剂、基底曲率等),评述了蜂窝状多孔薄膜的性质和应用,并对其在化学和材料科学领域的应用前景作了展望. 相似文献
16.
Hartmut Gliemann Arlete Tavares Almeida Denise Freitas Siqueira Petri Thomas Schimmel 《Surface and interface analysis : SIA》2007,39(1):1-8
The influence of relative humidity (RH) during the film preparation on the surface morphology and on the material distribution of the resulting technical polymer blend films consisting of poly (methyl methacrylate) (PMMA) and poly (vinyl butyral) (PVB) is investigated by atomic force microscopy. Both pure polymers and polymer blends with different compositions of PVB/PMMA dissolved in tetrahydrofuran (THF) were used. Polymer films prepared under dry conditions (RH < 20%) are compared with those that have the same polymer composition but were prepared under increased humidity conditions (RH > 80%). The films consisting of the pure polymers showed a nonporous surface morphology for low‐humidity preparation conditions, whereas high‐humidity preparation conditions lead to porous PVB and PMMA films, respectively. These pores are explained as the result of a breath figure formation. In the case of the polymer blend films containing both polymers, porous or phase‐separated surface structures were observed even at low‐humidity conditions. A superposition of the effects of phase separation and breath figure formation is observed in the case of polymer blend films prepared under high‐humidity conditions. Atomic force microscopy (AFM) images taken before and after the treatment with ethanol as a selective solvent for PVB indicate that PMMA is deposited on top of a PVB layer in the case of the low‐humidity preparation process whereas for high‐humidity conditions the silicon substrate is covered with a PMMA film. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
17.
《Journal of Polymer Science.Polymer Physics》2018,56(14):1035-1044
D‐A copolymer systems have unique characteristics, such as low band gap and ambipolar nature, which are important to design electronic polymer devices. In this contribution, we synthesized and characterized a D‐A random copolymer containing bis‐3‐hexylthiophene‐benzothiadiazole as acceptor unit and 9,9‐dioctylfluorene as donor unit. We show that the polymeric film morphology depends of the Hansen solubility parameters, evaporation rate, and surface tension of the solvent. Chloroform, toluene, and 1,2,4‐trichlorobenzene (TCB) promote the formation of self‐assembled structures due to breath‐figure mechanism. In contrast, THF causes aggregation and phase separation that affect negatively the electrical conductivity of the copolymer film. Among the solvents analyzed, TCB is the one with the highest molecular interaction with the copolymer synthetized in this work. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1035–1044 相似文献
18.
呼吸图案法制备蜂窝状有序多孔薄膜及其功能化应用 总被引:1,自引:0,他引:1
呼吸图案(BF)法是一种制备微纳米级规整多孔结构的简单、廉价和高效的方法, 它以水滴为模板, 通过水滴有序排列得到蜂窝状有序多孔结构, 其孔的形貌可以通过选择不同的成膜材料和成膜环境等条件得到控制, 所以在分离膜、模板、响应性表面、催化剂、光电材料等研究领域有广阔的发展前景. 但是, 到目前为止, 人们发现由于成膜条件的不同, 多孔膜的孔形貌受多种因素影响, 规整多孔膜形貌的控制机理还不是很明确, 没有一个统一的结论. 本文结合本课题组所做工作及近五年来国内外呼吸图案法制备蜂窝状有序多孔薄膜的研究成果, 对多孔薄膜的形成过程及其影响因素、多孔膜的功能化及应用等方面进行了归纳总结, 试图揭示孔的形成及孔形貌的调控等相关规律, 希望对后续的进一步研究与应用奠定基础. 相似文献
19.
Rongrong Hu Jacky W. Y. Lam Min Li Haiqin Deng Jie Li Ben Zhong Tang 《Journal of polymer science. Part A, Polymer chemistry》2013,51(22):4752-4764
A tetraphenylethene‐containing A4‐type tetrayne, named 1,1,2,2‐tetrakis(4‐ethynylphenyl)ethene is synthesized and its TaCl5‐Ph4Sn catalyzed homopolycyclotrimerization affords hyperbranched poly(tetraphenylethene) with high molecular weight (Mw = 280,000) in high yield (97%). The polymer shows good solubility and high thermal stability. It is aggregation‐enhanced emission (AEE)‐active and functions as a fluorescent chemosensor for explosive detection with a superamplification effect and large quenching constants up to 758,000 M?1. The polymer shows high and tunable refractive indices (RI = 1.9288?1.6746) in a wide wavelength region. Porous fluorescent polymer thin film is prepared by breath figure (BF) methods and real‐time monitoring of the elusive BF formation process is realized. Photolithography of the thin films readily generates well‐resolved fluorescent photopattern without and with porous secondary structure. The polymer is metallified and pyrolysed to give magnetic ceramics with high magnetic susceptibilities (Ms = 83 emu/g) and near‐zero coercivity (Hc = 0.08 kOe). © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 4752–4764 相似文献
20.
A novel organic/inorganic hybrid honeycomb patterned porous thin film was prepared using the breath‐figure method combined with a sol‐gel process. An in situ formed gelable block copolymer, formed by mixing poly(styrene‐alt‐maleic anhydride)‐block‐polystyrene (P(St‐a‐MAn)‐b‐PS) and 3‐aminopropyltrimethoxysilane (APS), was used as the structure directing agent. The porous film produced was dipped into an acid aqueous solution to induce a sol‐gel process in the wall of film. As a result of gelation, the structure of this film transformed into a crosslinked silica oxide hybridized with PS, and this film resisted those organic solvents which were once good solvents for the copolymer precursor.