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2604. Duncan, B., R. Mera, D. Leatherdale, M. Taylor, and R. Musgrove, “Techniques for characterising the wetting,. coating and spreading of adhesives on surfaces (NPL Report DEPC MPR 020),” National Physical Laboratory, Mar 2005.

2547. Kwon, O.-J., S. Tang, S.-W. Myung, N. Lu, and H.-S. Choi, “Surface characteristics of polypropylene film treated by an atmospheric pressure plasma,” Surface and Coatings Technology, 192, 1-10, (Mar 2005).

After the atmospheric pressure plasma treatment of polypropylene (PP) film surface, we measured the contact angle of the surface by using polar solvent (water) and nonpolar solvent (diiodomethane). We also calculated the surface free energy of PP film by using the measured values of contact angles. And then we analyzed the change of the contact angle and surface free energy with respect to the conditions of atmospheric pressure plasma treatment. Upon each condition of atmospheric pressure plasma treatment, the contact angle and surface free energy showed optimum value or leveled off. Through AFM analysis, we also observed the change of surface morphology and roughness before and after plasma treatment. The surface roughness of PP film showed the highest value when the plasma treatment time was 90 s. Finally, we analyzed the change of chemical compositions on the PP film surface through XPS. As the result of analysis, we observed that polar functional groups, such as –CO, –C=O, and –COO were introduced on the PP film surface after atmospheric pressure plasma treatment.

2534. Wang, M.-J., Y.-I. Chang, and F. Poncin-Epaillard, “Acid and base functionalities of nitrogen and carbon dioxide plasma-treated polystyrene,” Surface and Interface Analysis, 37, 348-355, (Mar 2005).

The choice of plasma gas can determine the interaction between material and plasma and therefore the applications of the treated materials. Nitrogen plasma can integrate functional groups such as primary amines and carbon dioxide plasma can incorporate carboxylic groups on the surface of polymers. For specific adhesion such as bio-adhesion, polar groups must be attached to the surface to enhance bio-film formation but the acidic or basic character also controls the adhesion mechanism.

Nitrogen and carbon dioxide plasmas are chosen to treat the surface of polystyrene and to show the effects of different functionalizations, i.e. attachment of acid or basic groups and degradation are compared in the present work.

Nitrogen-containing plasma induces mainly weak degradation at a rate of ∼0.13 µg cm−2s−1. The roughness of the treated surface remains mostly unchanged. Functionalization leads to amino group attachment at a concentration of 1.2 sites nm−2. We found that carbon dioxide plasma treatment shows more drastic degradation with a rate three times higher than that of nitrogen plasma and can create more functional groups (4.5 sites nm−2) at mild plasma treatment. However, the roughness of the surface is altered. In both cases the aromatic groups are degraded through the plasma treatment (again this is more evident with the CO2 plasma) and the induced functionalization was shown to be quick (the upper monolayer of polystyrene film can be functionalized rapidly). Copyright © 2005 John Wiley & Sons, Ltd.
https://analyticalsciencejournals.onlinelibrary.wiley.com/doi/abs/10.1002/sia.2029

2416. Ahmed, Q.U., M.D. Christy, and P.A. Wallis, “Treatment of plastics containers,” U.S. Patent 6866810B2, Mar 2005.

1164. Wolf, R.A., “Atmospheric plasma: a new surface treatment technology for promoting flexographic printing adhesions',” in 2005 FFTA Forum, Flexographic Technical Association, Mar 2005.

1115. Grace, J.M., Plasma Web Treatment, Society of Vacuum Coaters, Mar 2005.

3021. Zenkiewicz, M., “Effects of electron-beam irradiation on wettability and surface free energy of a polypropylene film,” Intl. J. Adhesion and Adhesives, 25, 61-66, (Feb 2005).

Effect of the electron radiation generated by a high-voltage linear accelerator on the wettability, contact angle and surface free energy (SFE) of a biaxially oriented polypropylene (BOPP) film was studied. Radiation doses of 25, 50, 100, 250, and 500kGy were used. Water, glycerol, formamide, diiodomethane, and α-bromonaphthalene were applied as measuring liquids. The calculations of SFE were made with the methods of Owens–Wendt and van Oss–Chaudhury–Good, using the results of measurements of the contact angle with various sets of the measuring liquids. Wettability tests were also performed. It was found that the contact angle decreased with the rising radiation dose for all the measuring liquids and the shapes of these dependences were similar to one another. However, significant quantitative differences were observed. The largest changes in the contact angle were detected in the dose range of up to 100kGy. The SFE values when measured with different methods and various measuring liquids differed generally in the whole range of the applied doses. Therefore, the surface free energy cannot be accepted as an absolute measure of the thermodynamic state of the surface layer of a radiation-modified BOPP film. Its values can be compared with one another only when they were determined with the same method and same measuring or standard liquids.

2584. Temmerman, E., Y. Ashikev, N. Trushkin, C. Leys, and J. Verschuren, “Surface modification with a remote atmospheric pressure plasma DC glow discharge and surface streamer regime,” J. Physics D: Applied Physics, 38, 505-509, (Feb 2005).

A remote atmospheric pressure discharge working with ambient air is used for the near room temperature treatment of polymer foils and textiles of varying thickness. The envisaged plasma effect is an increase in the surface energy of the treated material, leading, e.g., to a better wettability or adhesion. Changes in wettability are examined by measuring the contact angle or the liquid absorptive capacity. Two regimes of the remote atmospheric pressure discharge are investigated: the glow regime and the streamer regime. These regimes differ mainly in power density and in the details of the electrode design. The results show that this kind of discharge makes up a convenient non-thermal plasma source to be integrated into a treatment installation working at atmospheric pressure.

747. Markgraf, D.A., “Surface treatment,” in Film Extrusion Manual: Process, Materials, Properties, 2nd Ed., Butler, T.I., 287-311, TAPPI Press, Feb 2005.

2278. Barni, R., C. Riccardi, E. Selli, M.R. Massafra, B. Marcandelli, et al, “Wettability and dyeability modulation of poly(ethylene terephthalate) fibers through cold SF6 plasma treatment,” Plasma Processes and Polymers, 2, 64-72, (Jan 2005).

Surface modification induced on poly(ethylene terephthalate) (PET) fibers by cold SF6 plasma treatment has been investigated systematically as a function of plasma device parameters. The observed wettability modifications of fibers plasma-treated under different operating conditions were correlated to their dyeability modifications and to the changes in surface chemical composition, determined by X-ray Photoelectron Spectroscopy (XPS), and topography, investigated by atomic force microscopy (AFM). Optical emission spectra from the SF6 plasma at different pressures gave information on its content of fluorine atoms. A striking transition was observed between the increased hydrophilicity and high dyeability, imparted by plasma treatment at low pressure (<0.2 mbar), mainly as a consequence of surface etching and surface activation, and the increased hydrophobicity, imparted by plasma treatment in the higher pressure regime (0.2–0.4 mbar), consequent to extended surface fluorination.

2080. Kull, K.R., M.L. Steen, and E.R. Fisher, “Surface modification with nitrogen-containing plasmas to produce hydrophilic, low-fouling membranes,” J. Membrane Science, 246, 203-215, (Jan 2005).

Nitrogen-based plasma systems such as N2, NH3, Ar/NH3, and O2/NH3 were used to modify microporous polyethersulfone membranes. Treatments were designed to alter the surface chemistry of the membranes to create permanently hydrophilic surfaces. Contact angle measurements taken initially, as well as 1 year post-treatment confirmed that treatments using O2/NH3 plasmas (with a 5:3 gas flow ratio) were successful in achieving our designed goals. Analyses by FT-IR and XPS established the incorporation of NHx and OH species in the PES membranes. Moreover, the plasma penetrates the thickness of the membrane, thereby modifying the entire membrane cross-section. Optical emission spectroscopy studies of excited state species present in the modifying gases revealed the presence of OH*, which was not present in a 100% ammonia plasma, suggesting OH* must play a critical role in the membrane modification process. Investigations using bubble point analysis, differential scanning calorimetry, and scanning electron microscopy demonstrate there is no damage occurring under these specific treatment conditions. The usefulness of this treatment is revealed by increased water flux, reduced protein fouling, and greater flux recovery after gentle cleaning when compared to an untreated membrane.

1259. Tavana, H., N. Petong, A. Hennig, K. Grundke, and A.W. Neumann, “Contact angles and coating film thickness,” J. Adhesion, 81, 29-39, (Jan 2005).

The effect of film thickness and surface preparation techniques on contact angles of water, 1-bromonaphtalene, and n-hexadecane on Teflon® AF 1600 polymeric surfaces is studied. It was found that contact angles of water on different thicknesses of spin-coated films ranging from 27 nm to 420 nm are essentially constant. This is due to the homogeneity and smoothness of the coating layers as shown by the scanning force microscopy of the samples. Furthermore, the contact angle measurements with these three liquids on both dip-coated and spin-coated films suggested that the film preparation technique does not affect contact angles dramatically. Interestingly, slightly higher contact angles on dip-coated surfaces were measured. It is also argued that the anomaly of the water contact angle—in the sense that the measured contact angle is much higher than the expected ideal value—is due to specific interactions between water and Teflon®.

1111. Gilbertson, T.J., “Double treat it,” Package Printing, 52, 33, (Jan 2005).

1110. Sharon, K., “Special treatment,” Package Printing, 52, 30-34, (Jan 2005).

1109. Genuario, L., “Surface treatment,” Label and Narrow Web, 10, 50-56, (Jan 2005).

2995. Cho, J.H., B.K. Kang, K.S. Kim, B.K. Choi, S.H. Kim, and W.Y. Choi, “Hydrophilic effect of the polyimide by atmospheric low-temperature plasma treatment,” J. Korean Institute of Electrical and Electronic Material Engineers, 18, 148-152, (2005).

Atmospheric low-temperature plasma was produced using dielectric barrier discharge (DBD) plate-type plasma reactor and high frequency of 13.56 Hz. The surfaces of polyimide films for insulating and packaging materials were treated by the atmospheric low-temperature plasma. The contact angle of 67 was observed before the plasma treatment. The contact angle was decreased with deceasing the velocity of plasma treatment. In case of oxygen content of 0.2 %, electrode gap of 2 mm, the velocity of plasma treatment of 20 mm/sec, and input power of 400 W, the minimum contact angle of 13 was observed. The chemical characteristics of polyimide film after the plama treatment were investigated using X-ray photoelectron spectroscopy (XPS), and new carboxyl group bond was observed. The surfaces of polyimide films were changed into hydrophilic by the atmospheric low-temperature plasma. The polyimide films having hydrophilic surface will be very useful as a packaging and insulating materials in electronic devices.

2762. Eckert, W., “Comparison of corona and flame treatment of polymer film, foil and paperboard,” in 2005 European PLACE Conference Proceedings, TAPPI Press, 2005.

2757. Weber, R., “Saturation phenomena in conjunction with corona treatment on different substrates,” in 2005 European PLACE Conference Proceedings, TAPPI Press, 2005.

2581. Lahti, J., “Dry toner-based electrophotographic printing on extrusion coated paperboard (PhD thesis),” Tampere University of Technology, 2005.

2559. Sira, M., D. Trunec, P. Stahel, V. Bursikova, Z. Navratil, and J. Bursik, “Surface modification of polyethylene and polypropylene in atmospheric pressure glow discharge,” J. Physics D: Applied Physics, 38, 621-627, (2005).

An atmospheric pressure glow discharge (APGD) was used for surface modification of polyethylene (PE) and polypropylene (PP). The discharge was generated between two planar metal electrodes, with the top electrode covered by a glass and the bottom electrode covered by the treated polymer sample. The discharge burned in pure nitrogen or in nitrogen-hydrogen or nitrogen-ammonia mixtures. The surface properties of both treated and untreated polymers were characterized by scanning electron microscopy, atomic force microscopy, surface free energy measurements and x-ray photoelectron spectroscopy. The influence of treatment time and power input to the discharge on the surface properties of the polymers was studied. The ageing of the treated samples was investigated as well. The surface of polymers treated in an APGD was homogeneous and it had less roughness in comparison with polymer surfaces treated in a filamentary discharge. The surface free energy of treated PE obtained under optimum conditions was 54 mJ m-2 and the corresponding contact angle of water was 40° the surface free energy of treated PP obtained under optimum conditions was 53 mJ m-2 and the contact angle of water 42°. The maximum decrease in the surface free energy during the ageing was about 10%.

2513. Fridman, A., A. Chirokov, and A. Gutsol, “Non-thermal atmospheric pressure discharges,” J. Physics D: Applied Physics, 38, R1-R24, (2005).

There has been considerable interest in non-thermal atmospheric pressure discharges over the past decade due to the increased number of industrial applications. Diverse applications demand a solid physical and chemical understanding of the operational principals of such discharges. This paper focuses on the four most important and widely used varieties of non-thermal discharges: corona, dielectric barrier, gliding arc and spark discharge. The physics of these discharges is closely related to the breakdown phenomena. The main players in electrical breakdown of gases: avalanches and streamers are also discussed in this paper. Although non-thermal atmospheric pressure discharges have been intensively studied for the past century, a clear physical picture of these discharges is yet to be obtained.

2236. Lewin, M., A. Mey-Marom, and R. Frank, “Surface free energies of polymeric materials, additives and minerals,” Polymers for Advanced Technologies, 16, 429-441, (2005).

2183. Wolf, R.A., and A.C. Sparavigna, “The plasma advantage,” Textile World, 155, 49-51, (2005).

2182. Wolf, R.A., and A.C. Sparavigna, “Plasma revolution in flexible package printing,” Converter: Flessibili, Carta, Cartone, 57, 14-26, (2005).

1852. Forsstrom, J., M. Eriksson, and L. Wagberg, “A new technique for evaluating ink-cellulose interactions: Initial studies of the influence of surface energy and surface roughness,” J. Adhesion Science and Technology, 19, 783-798, (2005).

Ink–cellulose interactions were evaluated using a new technique in which the adhesion properties between ink and cellulose were directly measured using a Micro-Adhesion Measurement Apparatus (MAMA). The adhesion properties determined with MAMA were used to estimate the total energy release upon separating ink from cellulose in water. The total energy release was calculated from interfacial energies determined via contact angle measurements and the Lifshitz–van der Waals/acid–base approach. Both methods indicated spontaneous ink release from model cellulose surfaces, although the absolute values differed because of differences in measuring techniques and different ways of evaluation. MAMA measured the dry adhesion between ink and cellulose, whereas the interfacial energies were determined for wet surfaces. The total energy release was linked to ink detachment from model cellulose surfaces, determined using the impinging jet cell. The influences of surface energy and surface roughness were also investigated. Increasing the surface roughness or decreasing the surface energy decreased the ink detachment due to differences in the molecular contact area and differences in the adhesiom properties.

1770. Fu, R.K.Y., I.T.L. Cheung, Y.F. Mei, et al, “Surface modification of polymeric materials by plasma immersion ion implantation,” Nuclear Instruments and Methods in Physics Research, B237, 417-421, (2005).

Polymer surfaces typically have low surface tension and high chemical inertness and so they usually have poor wet-ting and adhesion properties. The surface properties can be altered by modifying the molecular structure using plasma immersion ion implantation (PIII). In this work, Nylon-6 was treated using oxygen/nitrogen PIII. The observed improvement in the wettability is due to the oxygenated and nitrogen (amine) functional groups created on the polymer surface by the plasma treatment. X-ray photoelectron spectroscopy (XPS) results show that nitrogen and oxygen plasma implantation result in C–C bond breaking to form the imine and amine groups as well as alcohol and/or car-bonyl groups on the surface. The water contact angle results reveal that the surface wetting properties depend on the functional groups, which can be adjusted by the ratio of oxygen–nitrogen mixtures.

1731. Bradley, J.M., “Determining the dispersive and polar contributions to the surface tension of water-based printing ink as a function of surfactant surface excess,” J. Physics D: Applied Physics, 38, 2045-2050, (2005).

The surface tension of a model, water-based, flexographic printing ink was measured at a range of surfactant concentrations along with the equilibrium contact angle formed with polymer substrates. The surface excess of surfactant at each concentration was calculated using the Gibbs adsorption isotherm and assumed equal to the concentration of surfactant at the interface. The change in the surface tension of the ink formulation was assumed to be determined entirely by the surface concentration of surfactant. This allowed the estimation of the surface tension at the solid–liquid and solid–vapour boundaries when in contact with substrate based on the values obtained for pendant drops. The associated polar and dispersive contributions to the surface tension were then calculated using the Young–Dupré equation. The values of the polar and dispersive surface tension components extracted in this manner were compared with those calculated using the approach of van Oss, Chaudhury and Good. The use of surface excess in estimating the contributions to surface tension was found to give far better agreement with experimental data than the van Oss approach which is intended for use with pure liquids.

1683. Roth, J.R., J. Rahel, X. Dai, and D.M. Sherman, “The physics and phenomenology of one atmosphere uniform glow discharge plasma (OAUGDP) reactors for surface treatment applications,” J. Physics D: Applied Physics, 38, 555-567, (2005).

In this paper, we present data on the physics and phenomenology of plasma reactors based on the One Atmosphere Uniform Glow Discharge Plasma (OAUGDP) that are useful in optimizing the conditions for plasma formation, uniformity and surface treatment applications. It is shown that the real (as opposed to reactive) power delivered to a reactor is divided between dielectric heating of the insulating material and power delivered to the plasma available for ionization and active species production. A relationship is given for the dielectric heating power input as a function of the frequency and voltage at which the OAUGDP discharge is operated.

1664. no author cited, “Surface treatment,” http://www.jobshop.com/techinfo/papers/surfacetreatment.shtml, 2005.

1661. Tuominen, M., and J. Kuusipalo, “The effects of flame treatment on clay coated paperboard in extrusion coating,” in 2005 European PLACE Conference Proceedings, TAPPI Press, 2005.

1579. d'Agostino, R., P. Favia, C. Oehr, and M.R. Wertheimer, “Low-temperature plasma processing of materials: past, present, and future,” Plasma Processes and Polymers, 2, 7-15, (2005).

Plasma, considered as the fourth state of matter, is playing a key role as a modern discipline. Plasma processing is drawing attention from various technology sectors such as microelectronics, automotive, and surface modifications of polymers. Some examples of additional new applications include functional coatings for architectural glass, mercury-free lamps, plasma-treated packaging for food, beverage and pharmaceutical industries, as well as nanomaterials. With the emergence of all new technological applications from basic research in academic, industrial, or government laboratories, plasma is set to have a brilliant future.

1526. Massines, F., “Atmospheric pressure non-thermal plasmas for processing and other applications,” J. Physics D: Applied Physics, 38, (2005).

Interest has grown over the past few years in applying atmospheric pressure plasmas to plasma processing for the benefits this can offer to existing and potential new processes, because they do not require expensive vacuum systems and batch processing. There have been considerable efforts to efficiently generate large volumes of homogeneous atmospheric pressure non-thermal plasmas to develop environmentally friendly alternatives for surface treatment, thin film coating, sterilization, decontamination, etc.

Many interesting questions have arisen that are related to both fundamental and applied research in this field. Many concern the generation of a large volume discharge which remains stable and uniform at atmospheric pressure. At this pressure, depending on the experimental conditions, either streamer or Townsend breakdown may occur. They respectively lead to micro-discharges or to one large radius discharge, Townsend or glow. However, the complexity arises from the formation of large radius streamers due to avalanche coupling and from the constriction of the glow discharge due to too low a current. Another difficulty is to visually distinguish many micro-discharges from one large radius discharge. Other questions relate to key chemical reactions in the plasma and at the surface. Experimental characterization and modelling also need to be developed to answer these questions.

This cluster collects up-to-date research results related to the understanding of different discharges working at atmospheric pressure and the application to polymer surface activation and thin film coating. It presents different solutions for generating and sustaining diffuse discharges at atmospheric pressure. DC, low-frequency and radio-frequency excitations are considered in noble gases, nitrogen or air. Two specific methods developed to understand the transition from Townsend to streamer breakdown are also presented. They are based on the cross-correlation spectroscopy and an electrical model.

1351. Murokh, I.Y., “In-Line Plasma Treatment of Wire Insulation Materials,” Tri-Star Technologies, 2005.

1347. Murokh, I.Y., “Atmospheric plasma surface treatment technique,” http://Tri-Star-Technologies/news/articles/atmosphericplasmasurfacetreatment.pdf, 2005.

1346. Greig, S., “Web Treatment - Going Solventless,” Sherman Treaters Ltd., 2005.

1131. Kim, B.G., E.-H. Son, S.-E. Kim, and J.-C. Lee, “Surface properties of the novel fluoropolymer having extremely low surface energy,” PMSE Preprints, 93, 610-611, (2005).

1130. Sardella, E., R. Gristina, G.S. Senesi, R. d'Agostino, and P. Favia, “Plasma-aided micropatterning of polystyrene substrates for driving cell adhesion and spreading,” in Plasma Processes and Polymers, d'Agostino, R., P. Favia, C. Oehr, and M.R. Wertheimer, eds., 373-388, Wiley-VCH, 2005.

Coatings with polyethylene oxide (PEO)-like films deposited by RF (13.56 MHz) glow discharges and featuring a total cell-repulsive effect were deposited on polystyrene (PS) samples. Substrates containing tracks of PS of petri dishes surrounded by PEO-like domains have been prepared with a good spatial resolution by using a masking procedure. The behavior of the substrates after seeding NCTC2544 human keratinocytes and 3T3Murine fibroblasts has been studied. It has been found that also PS tracks are able to drive cells up to confluence, provided that a longer incubation time is provided. A phenomenological interpretation is suggested.

1129. Favia, P., A Milella, L. Iacobelli, and R. d'Agostino, “Plasma pretreatments and treatments on polytetrafluoroethylene for reducing the hydrophobic recovery,” in Plasma Processes and Polymers, d'Agostino, R., P. Favia, C. Oehr, and M.R. Wertheimer, eds., 271-280, Wiley-VCH, 2005.

Different plasma treatments (NH3, O2) were carried out on polytetrafluoroethylene (PTFE) for grafting polar groups and obtaining a stable, permanent hydrophilic surface. Plasma pretreatments (H2 and Ar) were also utilized to limit the aging, including the hydrophobic recovery, of the treated surface with time. Dynamic water contact-angle (WCA) measurements and X-ray photoelectron spectroscopy (XPS) analyses were performed to study in depth the chemical compositional changes as a function of ageing time. This paper illustrates mainly the remarkable effect of combining H2 plasma pretreatments with low-power NH3 plasma treatments for obtaining stable PTFE surfaces grafted with polar groups that exhibit permanent wettability. The results were expressed in terms of the fractions of mobile and immobile polar grafted groups.

1128. Laurens, P., S. Petit, P. Bertrand, and F. Arefi-Khonsari, “PET surface after plasma or laser treatment:Study of the chemical modifications and adhesive properties,” in Plasma Processes and Polymers, d'Agostino, R., P. Favia, C. Oehr, and M.R. Wertheimer, eds, 253-270, Wiley-VCH, 2005.

The chemical modifications induced on PET by an excimer laser radiation or a lowpressure plasma were studied by XPS and Tof SIMS analyses. Both treatments induced surface oxidation but differences related to the type of oxidized groups and the level of degradation of the treated surface were evidenced. Both treatments can significantly enhance the adhesion but the surface change responsible for the improvement was different for each pretreatment.

1127. Tyczkowski, J., I. Krawczyk, and B. Wozniak, “Plasma-surface modification of styrene-butadiene elastomers for improved adhesion,” in Plasma Processes and Polymers, d'Agostino, R., P. Favia, C. Oehr, and M.R. Wertheimer, eds., 233-252, Wiley-VCH, 2005.

An attempt to replace a wet-chemical surface modification of styrene-butadiene elastomers (SBS), improving their adhesion to polyurethane adhesives, with a clean low-pressure plasma technique has been undertaken. The plasma has been generated by an RF discharge (13.56 MHz, plate electrode reactor) in various reactive mixtures (eg CHCl3, CCl4, CO2, O2) to create chlorine (C–Cl) and oxygen (> C= O,–OH,–COOH) functionalities on the elastomer surfaces. T-peel tests, contact-angle measurements, and FTIR spectroscopy have been utilized to investigate the surfaces. It has been found that an important role in the plasma-improved adhesion is played by the chemical interaction between the modified SBS surfaces and polyurethanes. The peel strength for plasma-treated samples in many cases is much higher than that for the wetchemical modification. It clearly indicates that the plasma treatment is a very promising method of improving the adhesion properties of SBS

 

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