共查询到20条相似文献,搜索用时 203 毫秒
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T. Mathew R. N. Datta W. K. Dierkes J. W. M. Noordermeer W. J. van Ooij 《Plasma Chemistry and Plasma Processing》2008,28(2):273-287
Carbon black is widely used as an active filler in the rubber industry to improve the physical properties of rubber. The surface
energy of carbon black is high compared to that of various elastomers like styrene–butadiene rubber (SBR), butadiene rubber
(BR) and ethylene–propylene–diene rubber (EPDM). The work aims at reducing the surface energy of carbon black by modifying
its surface for application especially in rubber blends. The present paper looks into the possibility of using plasma polymerisation
of acetylene as a surface modification technique for carbon black in comparison with silica. Thermogravimetric analysis, wetting
behaviour with various liquids of known surface tension and time of flight secondary ion mass spectrometry (ToF-SIMS) were
used to characterise the carbon black before and after surface modification. The study shows that surface modification of
carbon black by plasma polymerisation is difficult in comparison with silica, unless treated for long duration. The mechanistic
aspects of the surface modification and the importance of active sites on the carbon black surface for effective modification
are discussed in the paper. 相似文献
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Roya Mohammadzadeh Kakhki 《Arabian Journal of Chemistry》2019,12(7):1783-1794
The unique properties of carbon fiber electrodes (CFEs) offer a number of particular advantages for their use in analytical applications. However, some pretreatment is usually necessary for the modification of the carbon surface. One of these methods is enzyme modification, that enzyme reactions in the surface of the electrode can be useful for the certain determinations. Also application of nanoparticles is very useful for modification and gives very interesting responses for the electrode in the determination of various analytes. Electrochemical oxidation of a carbon surface is one of the other methods for modification. With this work the morphology of the surface changes as well as increasing the coverage by various oxygen-containing functional groups. These groups can then interact and bind with other species introduced to the surface. The modification of the surface of carbon fiber electrodes is an interesting topic with many applications in the fields of analytical chemistry, environmental and health science, fuel cell and biofuel cell and many others. In this review article we discussed about the various modification methods for carbon fiber electrodes and applications of these CFEs. 相似文献
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采用固相表面修饰方法对聚丙烯进行网络修饰,讨论了反应条件对体系凝胶分数的影响,用IR、WAXD、DSC、DMA和电子能谱等方法研究了固相表面修饰对聚丙烯结晶性能的影响,阐明了固相表面修饰过程的特点. 相似文献
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In numerous applications in microfluidics, cell growth, soft lithography, and molecular imprinting, the surface of poly(dimethylsiloxane) (PDMS) is modified from a hydrophobic methyl-terminated surface to a hydrophilic hydroxyl-terminated surface. In this study, we investigated molecular structural and orientational changes at the PDMS-air interface in response to three commonly used surface modification processes: exposure to long-wavelength ultraviolet light (UV), exposure to short-wavelength UV that generates ozone (UVO), and exposure to oxygen plasma (OP). The surfaces of two PDMS compositions (10:1 and 4:1 of base polymer/curing agent) were probed during modification, using monolayer-sensitive IR + visible sum frequency generation (SFG) vibrational spectroscopy, with two different polarization combinations. During PDMS surface modification, the peak intensities of CH3 side groups and CH2 cross-link groups decreased, while peak intensities of Si-OH groups increased. There was no significant change in the average orientation of the CH3 groups on the PDMS surface during modification. The concentration of CH3 groups on the surface decreased exponentially with time, for all three UV, UVO, and OP modification processes, with first order kinetics and time constants of approximately 160, 66, and 0.3 min, respectively. At steady state, residual CH3 groups were detected at the PDMS surface for UV and UVO treatments; however, there were negligible CH3 groups detected after OP modification. 相似文献
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Tinneke Jacobs Rino Morent Nathalie De Geyter Peter Dubruel Christophe Leys 《Plasma Chemistry and Plasma Processing》2012,32(5):1039-1073
Polymers are commonly used in industry because of their excellent bulk properties, such as strength and good resistance to chemicals. Their surface properties are for most application inadequate due to their low surface energy. A surface modification is often needed, and plasma surface modification is used with success the past decades. In the past few years, also plasma surface modification for biomedical polymers has been investigated. For biomedical polymers, the surface properties need to be altered to promote a good cell adhesion, growth and proliferation and to make them suitable for implants and tissue engineering scaffolds. This review gives an overview of the use of plasma surface modification of biomedical polymers and the influence on cell-material interactions. First, an introduction on cell-material interaction and on antibacterial and antifouling surfaces will be given. Also, different plasma modifying techniques used for polymer surface modification will be discussed. Then, an overview of literature on plasma surface modification of biopolymers and the resulting influence on cell-material interaction will be given. After an overview of plasma treatment for improved cell-material interaction, plasma polymerization and plasma grafting techniques will be discussed. Some more specialized applications will be also presented: the treatment of 3D scaffolds for tissue engineering and the spatial control of cell adhesion. Antibacterial and antifouling properties, obtained by plasma techniques, will be discussed. An overview of research dealing with antibacterial surfaces created by plasma techniques will be given, antifouling surfaces will be discussed, and how blood compatibility can be improved by preventing protein adhesion. 相似文献
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聚丙烯微孔膜表面的空气等离子体处理 总被引:5,自引:2,他引:5
采用空气等离子体对聚丙烯微孔膜进行了处理,膜表面带有了氧元素,表面亲水性增强。微孔膜外表面改性程度较高,而孔内愈往深处改性程度愈弱。空气等离子体处理过的微孔膜力学性能下降。 相似文献
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Fengying Cai Yafeng Ren Jiajia Dai Jianmin Yang Xianai Shi 《Macromolecular bioscience》2023,23(3):2200379
Cell surface engineering technologies can regulate cell function and behavior by modifying the cell surface. Previous studies have mainly focused on investigating the effects of cell surface engineering reactions and materials on cell activity. However, they do not comprehensively analyze other cellular processes. This study exploits covalent bonding, hydrophobic interactions, and electrostatic interactions to modify the macromolecules succinimide ester-methoxy polyethylene glycol (NHS-mPEG), distearoyl phosphoethanolamine-methoxy polyethylene glycol (DSPE-mPEG), and poly-L -lysine (PLL), respectively, on the cell surface. This work systematically investigates the effects of the three surface engineering reactions on the behavior of human umbilical vein endothelial cells (HUVECs) and human skin fibroblasts, including viability, growth, proliferation, cell cycle, adhesion, and migration. The results reveals that the PLL modification method notably affects cell viability and G2/M arrest and has a short modification duration. However, the DSPE-mPEG and NHS-mPEG modification methods have little effect on cell viability and proliferation but have a prolonged modification duration. Moreover, the DSPE-mPEG modification method highly affects cell adherence. Further, the NHS-mPEG modification method can significantly improve the migration ability of HUVECs by reducing the area of focal adhesions. The findings of this study will contribute to the application of cell surface engineering technology in the biomedical field. 相似文献
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The cell membrane is a biological interface consisting of phospholipid bilayer, saccharides and proteins that maintains a stable metabolic intracellular environment as well as regulating and controlling the exchange of substances inside and outside the cell. Cell membranes provide a highly complex biological surface carrying a variety of essential surfaces ligands and receptors for cells to receive various stimuli of external signals, thereby inducing corresponding cell responses regulating the life activities of the cell. These surface receptors can be manipulated via cell surface modification to regulate cellular functions and behaviors Thus, cell surface modification has attracted considerable attention due to its significance in cell fate control, cell engineering and cell therapy. In this minireview, we describe the recent developments and advances of cell surface modification, and summarize the main modification methods with corresponding functions and applications. Finally, the prospect for the future development of the modification of the living cell membrane is discussed. 相似文献
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Post-synthetic surface modification of magnetite nanoparticles synthesized by a modified co-precipitation process was carried out with triethoxy-terminated perfluoropolyether (PFPE) oligomers. The chemisorption of PFPE oligomers on the surface of magnetites was confirmed by ATR-FTIR and TGA analyses. The efficiency of surface modification of the oligomer to prevent the aggregation of magnetite nanoparticles was studied with the dynamic light scattering technique by measuring the hydrodynamic diameter and polydispersity index of the surface treated nanoparticles, together with their zeta potential. Aggregation kinetics profiles were constructed for surface treated nanoparticles. The obtained data was compared with magnetite nanoparticles treated with critic acid, to assess the efficiency of the surface modification with the PFPE oligomers. The comparison showed that the bifunctional PFPE oligomer treated nanoparticles are characterized by improved colloidal stability and hydrophobicity. 相似文献
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Maillard products of beta-lactoglobulin (betaLg) and fructose oligosaccharide (FOS) were obtained in different degrees of modification depending on incubation time and pH. By use of a variety of biochemical and spectroscopic tools, it was demonstrated that the modification at limited degrees does not significantly affect the secondary, tertiary, and quaternary structure of betaLg. The consequence of the modification on the thermodynamics of the protein was studied using differential scanning calorimetry, circular dichroism, and by monitoring the fluorescence intensity of protein samples with different concentrations of guanidine-HCl. The modification leads to lowering of the denaturation temperature by 5 degrees C and a reduction of the free energy of stabilization of about 30%. Ellipsometry and drop tensiometry demonstrated that upon adsorption to air-water interfaces in equilibrium modified betaLg exerts a lower surface pressure than native betaLg (16 versus 22 mN/m). Moreover, the surface elastic modulus increased with increasing surface pressure but reached significantly smaller values in the case of FOS-betaLg. Compared to native betaLg, modification of the protein with oligofructose moieties results in higher surface loads and thicker surface layers. The consequences of these altered surface rheological properties are discussed in view of the functional behavior in technological applications. 相似文献
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