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A novel silane coupling agent bearing sulfobetaine group, N,N-diethyl-N-(3-sulfopropyl)-aminopropyl- trimethoxysilane (DESATS), was first designed, synthesized and characterized. Its solution property was studied by means of dynamic light scattering. DESATS was successfully bonded onto the surface of the glass and proved by ESCA. Platelet adhesion assay in vitro indicated that the nonthrombogenicity of glass slide modified with DESATS is greatly improved. 相似文献
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SURFACE OF GELATIN MODIFIED POLY(L-LACTIC ACID)FILM 总被引:1,自引:0,他引:1
In this paper, the surface structure of poly(L-lactic acid) (PLLA) film modified with gelatin was investigated. ThePLLA film specimens were treated directly with aqueous alkali solution to provide their surfaces with carboxyl groups, sothat these functional groups could become the reactive sites for gelatin immobilization. The functional groups of the PLLAfilms were identified by ATR-FTIR spectra and XPS spectra, the changes in surface morphology were observed by usingenvironmental scanning electron microscopy (ESEM), and the hydrophilicity of modified PLLA films was examined bywater contact angle measurement. Experimental results showed that the gelatin was immobilized with water-solublecarbodiimide (EDC) onto the PLLA film's surfaces, and the gelatin content on the polymer surface was related to carboxylicgroup formed in the controlled hydrolysis process. Rough surfaces caused by hydrolysis will predominantly favor the adhesion and growth of cell; and the hydrophilicity of these surfaces after the modification procedure is enhanced. 相似文献
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The graft copolymerization of acrylamide onto polypropylene (PP) Film was carried out by using a capacitively coupled rf plasma apparatus with external plate electrodes. The relationship between the surface structure of the Ar plasma-treated PP films and the extent of grafting of acrylamide on the films was studied through observing the effects of discharge power and exposure time on the relative content of free-radical on the film surface. Meanwhile, the wettability and surface energy of the PP film were measured. 相似文献
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DENG SuiPing OUYANG JianMing XIE YuShan XING FeiYue Institute of Biomineralization Lithiasis Research Jinan University Guangzhou China 《中国科学B辑(英文版)》2008,51(1):25-30
The injury of the renal epithelial cell membrane can promote the nucleation of nascent crystals, as well as adhesion of crystals on it. It thus accelerates the formation of renal calculi. In this paper, the defective Langmuir-Blodgett (LB) films were used as a model system to simulate the injured renal epithelial cell membrane. The microcosmic structure of the defective LB film and the molecular mechanism of the effect of this film on nucleation, growth, deposited patterns and adhesion of calcium oxalate monohydrate (COM) were investigated. The circular defective domains were formed in dipalmitoylphosphatidylcholine (DPPC) LB film after the film was treated by potassium oxalate. These domains could induce ring-shaped patterns of COM crystals. In comparison, the LB film without pretreatment by potassium oxalate only induced random growth of hexagonal COM crystals. As the crystallization time increased, the size of COM crystals in the patterns increased, the crystal patterns changed from empty circles to solid circles, and the number of the circular patterns with small size (5-20 μm) increased. The results would shed light on the molecular mechanism of urolithiasis induced by injury of the renal epithelial membrane at the molecular and supramolecular level. 相似文献
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A new phosphorylcholine, (6-hydroxy) hexyl-2-(trimethylammonio) ethyl phosphate (HTEP), was synthesized andcharasterized. Segmented polyurethane (SPU) containing phosphorylcholine structure was synthesized based ondiphenylmethane diisocyanate (MDI), soft segment polytetramethylene glycol (PTMG) and HTEP, with 1,4-butanediol (BD)as a chain extender. The existence of phosphorylcholine structure on the surface of SPU was revealed by attenuated totalreflectance Fourier transform infrard spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and water contactangle measurements. The blood compatibilities of the polymers were evaluated by hemolytic testing and a platelet-richplasma (PRP) adhesion experiment, which was viewed by scanning electron microscopy (SEM) with polyurethane as areference. The novel segmented polyurethane containing phosphorylcholine structure showed improved blood compatibility. 相似文献
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Adopting LB film method, an arachidic acid (AA)/PEDOT multilayer LB film and polymerized EDOT monomers in hydrophilic group of LB were chosen to prepare the arachidic acid (AA)/PEDOT multilayer LB film. UV-Vis, FT-IR and XPS analyses implied that EDOT was effectively polymerized in film, and thus PEDOT conducting polymer was produced. Analyses of XRR and SIMS indicated that the film had a well-arranged lamella structure, and further research showed that polymerization of EDOT in AA film destroyed the orderliness of the original LB film. This phenomenon could be related to the destructive effect of polymerization on the layered structure. We used four-point probe and semiconductor instrument to study the conductivity property of the film, and observed that the conductivity of AA/PEDOT film had sudden changes with the changes of processing time in an effective conduction network, which was caused by "permeability" in conducting channel of multilayer film. The test results also indicated that the conductivity of AA/PEDOT film was obviously better than that of spin-coating PEDOT/PSS or ODA-SA/PEDOT-PSS film due to the higher π structure of PEDOT structure and ordered film structure. 相似文献
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Transition metal selenides have been widely studied as anode materials of sodium ion batteries(SIBs),however,the investigation of solid-electrolyte-interface(SEI)on these materials,which is critical to the electrochemical performance of SIBs,remains at its infancy.Here in this paper,ZnSe@C nanoparticles were prepared from ZIF-8 and the SEI layers on these electrodes with and without reduced graphene oxide(rGO)layers were examined in details by X-ray photoelectron spectroscopies at varied charged/discharged states.It is observed that fast and complicated electrolyte decomposition reactions on ZnSe@C leads to quite thick SEI film and intercalation of solvated sodium ions through such thick SEI film results in slow ion diffusion kinetics and unstable electrode structure.However,the presence of rGO could efficiently suppress the decomposition of electrolyte,thus thin and stable SEI film was formed.ZnSe@C electrodes wrapped by rGO demonstrates enhanced interfacial charge transfer kinetics and high electrochemical performance,a capacity retention of 96.4%,after 1000 cycles at 5 A/g.This study might offer a simple avenue for the designing high performance anode materials through manipulation of SEI film. 相似文献
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ZhuoHua Yan RongPing Zhang YuRong Zhao Biao Zuo FanFan Zheng TianYu Chen XinPing Wang ZhiQuan Shen 《中国科学:化学(英文版)》2012,55(7):1263-1273
The surface chemical structure development in solution-cast styrene(S)/butadiene(B) block copolymer films as a function of solvent evaporation time was investigated using sum frequency generation vibrational spectroscopy(SFG).The surface structure formation of the styrene(S)/butadien(B) block copolymer(30 wt% PS) films during the solution-to-film process was found to be controlled mainly by dynamic factors,such as the mobility of the PB block in solution.For SB diblock copolymers,a pure PB surface layer was formed only when the film was cast by dilute toluene solution.With increasing concentration of casting solution,PB and PS components were found to coexist on the film surface,and the morphology of the PB component on the film surface changed from cylindrical rods to spheres.For SBS triblock copolymers,a small amount of PS component existed on the surface even if the film was cast by 1.0 wt% toluene solution.In addition,PS components at the outermost layer of the film increased and the length of PB cylindrical rods on the surface decreased with increasing concentration of casting solution. 相似文献
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Light-weight and high-strength materials have attracted considerable attention owing to their outstanding properties, such as weight-reducing, acoustic absorption, thermal insulation, shock and vibration damping. Diamond possesses specific stiffness and strength arising from its special crystal structure. In this work, inspired by the diamond crystal structure, hollow-tube nickel materials with the diamond structure were fabricated using a diamond structured polymer template based on the Stereo Lithography Appearance technology. The diamond structured template was coated with Ni-P by electroless plating. Finally, the template was removed by high temperature calcinations. The density of the hollow tube nickel materials is about 20 mg/cm3. The morphology and composition of the resultant materials were characterized by scanning electron microscope, energy-dispersive spectrometry, and X-ray diffraction. The results showed that the surface of the Ni film was uniform with the thickness of 4 μm.The mechanical property was also measured by stress and strain tester. The maximum compression stress can be reached to40.6 KPa. 相似文献
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Mercaptopropyltrimethoxysilane (MPTS) bearing mercapto groups was used to form self-assembly monolayers (SAMs) on glass substrates by solution extraction.SEM,XRD and rubbing test analysis illustrated that the Ag film on the SAMs-modified glass was more durable than that on the commonly-modified glass and that the crystallinity of Ag film on the SAMs-modified glass was identical with those of the Ag film on the commonly-modified glass and pure Ag. 相似文献
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Jun Zhou Yong-zhi Qiu Xiao-peng Zang Chang-wang Pan Qiang Chen Jian Shen Si-cong Lin 《高分子科学》2005,23(1)
N,N-dimethyl-N-methacryloyloxyethyl-N-carboxyethyl ammonium (DMMCA) was graft-copolymerized onto the surface of segmented poly(ether urethane) (SPEU) and PE film. The carboxybetaine structure on SPEU and PE film surfaces was confirmed by ATR-FTIR, XPS and water contact angle measurements. Through the experiments with platelet adhesion and protein adhesion assay in vitro, the two materials studied, including poly-DMMCA gel, all show excellent nonthrombogenicity. This confirms once again that the zwitterionic molecular structure on the surfaces of materials is essential for improving their nonthrombogenicity and biocompatibility. 相似文献
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本文主要研究了在溶液聚合中,用两种加料方式对嵌段聚醚氨酯(SPEU)本体形态结构的影响。由透射电镜观察的结果发现,在预聚反应过程中采用两种加料方式,其最终聚合产物(SPEU)都具有明显的两相结构;加料方式不同主要影响SPEU中分散相的形态和其内的聚集态结构:(1)采用将端羟基的聚四次甲基醚(PTMEG)溶液滴加到4,4′-二苯基甲烷二异氰酸酯(MDI)的溶液中,俟反应完成后再滴加入扩链剂(Extender)的加料方式所制得的SPEU其分散相在形态上呈现为小棒条状,这种分散微区的宽度一般在10—60nm范围内,从选区电子衍射结果证明这种微区的结构是结晶的。(2)而采用将MDI的溶液滴加到PTMEG溶液中,俟反应完成后再滴加Extender的加料方式所制备的SPEU其分散相在形态上呈现为球形,它们的直径多在100至300nm范围内,由电子衍射证明这种分散微区的结构是无定形的。 相似文献
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甲基丙烯酸聚乙二醇单甲醚酯在聚(醚-氨酯)表面的臭氧化接枝 总被引:5,自引:1,他引:5
甲基丙烯酸聚乙二醇单甲醚酯在聚(醚 氨酯)表面的臭氧化接枝王晨晖王安锋车波周彩华苏琳丽林思聪(南京大学高分子科学与工程系生物材料分子工程与控制释放分子工程室南京210093)王炳坤(南京大学环境科学系南京210093)关键词臭氧化,表面接枝,大... 相似文献
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抗凝血聚氨酯材料的研究进展 总被引:7,自引:0,他引:7
聚氨酯由于其优良的抗凝血性能和良好的物理机械性能而成为目前研究和应用最广的一种生物医用高分子材料。本文就嵌段型聚氨酯、拦枝型聚氨酯、离子型聚氨酯及其它具有良好发展前景的聚氨酯抗凝血材料的研究进展作扼要综述。 相似文献
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无光敏剂光引发亲水性单体在嵌段聚醚氨酯膜上接枝聚合的研究 总被引:3,自引:0,他引:3
<正> 嵌段聚醚氨酯(SPEU)是一类应用广泛的医用高分子材料。用亲水性单体进行表面接枝改性,已有不少研究,接枝聚合方法有铈盐引发、辐射引发以及光敏引发等。 本文研究一种新的接枝方法,不加光敏剂,用紫外光照射,直接引发亲水性单体接枝于SPEU膜上、接枝的单体有丙烯酰胺(AAM)与N,N-二甲基丙烯酰胺(DMAA),从接枝前后膜的性能变化可以证实接枝反应的发生。文中研究了反应条件与单体结构对接枝率的影响,并通过模型化合物,对接枝部位进行了研究。 相似文献
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The graft copolymerization of N-methacryl-N'-methyl-opiperazine onto segmented polye-therurethane (SPEU) film by Go60-r-preirradiation has been studied. It is found that the grafting time varies with structure of different chain extenders. The grafted substrated become opaque, the contact angle drops down and from SEM photographs with salient micrograph showing grafts of macrochain on the surface of SPEU film. 相似文献