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This paper reports on the behavior of red and black ink from a historical printed book, subjected to a plasma discharge treatment, applied for the decontamination and cleaning of naturally aged paper. As some preliminary experiments using high-frequency (HF) plasma showed a slight fading of red ink, the study was focused on the comparison of HF cold plasma and afterglow plasma treatments in order to get conclusive information on the effect of plasma active species on the red ink. Energy Dispersive X-ray Scanning Electron Microscopy SEM-EDX and Attenuated Total Reflection Fourier-Transform Infrared Spectroscopy FTIR-ATR analyses were used for the identification of inks and binder, while the impact of plasma on inks was assessed by SEM analysis and color determinations. The experiments have been performed on an especially designed modular equipment, allowing the samples to be subjected alternately to HF cold plasma or afterglow plasma treatment. The study proved that direct HF plasma could result in a more important deterioration at treatment duration exceeding 5 min, while in afterglow plasma, this discoloration is not observable. The color fading is imputable to the corrosion of pigment crystallites produced by direct plasma discharge. [ABSTRACT FROM AUTHOR]

The study establishes an adequate monomer combination for achieving the best balance of properties required in obtaining polyimide alignment layers for display devices. The molecular design of some aliphatic/aromatic polyimides was performed by using dianhydride monomers with distinct configurations in terms of rigidity, size, and symmetry. The polyimides based on semi-flexible and nonsymmetric dianhydride moieties present lower refractive index and dielectric constant (<3) than those obtained from symmetric and rigid dianhydride units. This determines faster traveling of visible and microwave radiations as required for liquid crystal alignment purposes. The interactions of samples with the N-(4-Methoxybenzylidene)-4-butylaniline, cyanobiphenyl, and 4-pentyl-4-cyanobiphenyl nematics were assessed. The analyzed polyimides have higher surface tensions than the ones of the liquid crystals, determining a parallel arrangement of the nematic molecules. As the dispersive interactions at the polymer surface are lower, the work of spreading is higher as a result of improved adhesion of liquid crystal with the polyimide alignment layer. The sample containing rigid, symmetric, noncoplanar dianhydride units (PI.4) and the one based on semi-flexible, nonsymmetric dianhydride moieties are the most transparent for visible and microwave radiations, allowing low cohesion interaction at interface with nematics. These aspects recommend the two studied polyimides as candidates for alignment layers. [ABSTRACT FROM AUTHOR]

Atomic force microscopy (AFM) was used to analyze rectangular 3‐dimensional patterned microstructures with different functionalities induced on copolyimide containing alicyclic sequences film surfaces by means of oxygen plasma treatment. The plasma power was ranged to be big enough to accelerate the plasma species towards the copolyimide surface, and the exposure time was not very small to generate a roughness that still can be monitored by AFM. To create the rectangular pattern, transmission electron microscopy grid masks were placed on the samples before treatment. Plasma‐induced micropatterning with alternating hydrophilic and hydrophobic surface chemistries was evaluated by measuring the adhesion forces between the gold‐covered AFM tip and the copolyimide surfaces. To fabricate 3‐dimensional metallic microstructures arranged in well‐defined areas, thin metal layers were sputtered on these pretreated copolyimide films. The AFM morphological aspects of the obtained metallic structures were correlated with the surface modifications induced by plasma treatment conditions. Functional indexes and functional volume parameters were also calculate to characterize the functional behavior of the surface, such as wear, lubrication, and contact. The AFM data were compared with those obtained using the small‐angle X‐ray scattering measurements. [ABSTRACT FROM AUTHOR]

This paper presents a radio frequency plasma equipment designed to be used for the conservation procedures, such as decontamination, cleaning, and consolidation of cellulose-based materials. Decontamination and cleaning are carried out by the low-temperature nitrogen plasma generated between two electrodes, connected to a 1.5-MHz generator. The paper consolidation is performed by coating with compatible polymers in view of long term protection. Surface analyses (color analysis and electron microscopy) were undertaken to assess the uniform display of the polymer on the paper surface. The microbiological tests made on representative samples collected from historical books attested the complete inhibition of bacteria and fungi after, at most, 7-min treatment duration, depending on the initial infestation degree. [ABSTRACT FROM AUTHOR]

ABSTRACT Surface wettability trends, and blood component adhesion of some cellulose acetate phthalate/hydroxypropyl cellulose blend films are analyzed in view of adapting the system to biomedical applications. The results show that intermediate blend compositions of the corresponding films influence the surface tension parameters-controlled by the interactions occurring in the system. Increasing hydrophobicity and, implicitly, decreasing the polar surface tension components, are correlated with the adhesion/cohesion of blood components and plasma proteins. Thus, the work of spreading proteins on the hydrophobic blend surfaces indicated that albumin is not absorbed preferentially, while fibrinogen is characterized by a higher degree of adhesion on the surfaces, and also that selective adsorption of plasma proteins modifies blood compatibility. In addition, the obtained results and the ascertained antimicrobial activity of the studied blends contribute to the development of new applications in the biomedical field. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41932 [ABSTRACT FROM AUTHOR]

The paper aims at assessing morphological and chemical changes on the surface of the cellulose-based materials, such as paper, induced by high frequency (HF) plasma discharge. The topic is discussed using capacitive coupled plasma discharge at 1.2 MHz, performed in Ar/O2 mixtures, on objects made up of natural polymers, such as lignocellulosic fibers. The preliminary findings indicate the possibility of using HF cold plasma discharge for obtaining the modified properties of the cellulose-based surfaces. Simultaneously, this treatment is well suited for cleaning and decontamination purposes. The improved wettability of the cellulose-based materials after surface activation in low pressure HF Ar/O2 plasma is favorable for a subsequent deposition of protective coating formulas specific in the conservation practices. [ABSTRACT FROM PUBLISHER]

The article describes some properties of cellulose acetates (CAs) with different substitution degrees. The hydrophilic/hydrophobic properties, morphological aspects, and interface properties with red blood cells and platelets are affected by the substitution degree, synthesis conditions, history of the formed films from solutions in acetone/water nonsolvent/nonsolvent mixtures, and low pressure plasma treatment. The results obtained are useful in biomedical applications, including evaluation of bacterial adhesion onto surfaces, or utilization of CA for semipermeable membranes. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

A novel quaternized polysulfone with N-dimethyloctylammonium groups was investigated with respect to its surface properties, hydrophobicity, interactions with blood, and morphology. The history of the films formed from N,N-dimethylformamide/methanol and N,N-dimethylformamide/water solutions and the compositions of the solvent/nonsolvent mixtures influenced the surface morphology. Thus, atomic force microscopy investigations of the films showed pores and nodules of different sizes and intensities, which depended on the content of methanol or water in the solvent mixtures. Hydrophilicity modification, evidenced by the apolar components and the electron-acceptor and electron-donor parameters of the polar components of the surface tension parameters, was correlated with atomic force microscopy data. Surface wettability trends were analyzed on the basis of the free energy of hydration between the prepared films and water and the work of adhesion. The adhesion of red blood cells to the modified polysulfone showed the influence of the hydrophobic properties. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]