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The aim of this research was to apply three different types of zeolites and the combination thereof in the form of a very fine powder, together with different chemicals and additives on polyamide knitted fabric according to an industrially acceptable exhaustion procedure in order to study changes in the morphology, optical properties and wettability of surfaces. Zeolites were analysed using Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and gas physiosorption. Additionally, the morphology of zeolite-coated surfaces was examined closely using SEM, while changes in molecular-chemical level were examined by means of IR spectroscopy. Optical properties were studied using CIE colour measurement and diffuse refl ectance profile determination, while the hydrophilic/hydrophobic character was examined using goniometry. The obtained results show the suitability of the employed exhaustion procedure, depending on the type of zeolite and the composition of the treatment bath. The results also provided evidence of the enhanced wettability of PA fabrics using 4A and 13X zeolites in combination with selected additives.

Non-woven cellulose material was functionalized using two techniques, i.e. the coating with AgCl via solgel and oxygen plasma. The treatment eff ects were studied regarding the wound fl uid adsorption potential using physiological saline, synthetic exudate and synthetic blood. Plasma treatment was most effi cient since a signifi cant improvement by absorbency rate and capacity was evident, less pronounced in case of synthetic blood. The combination of both treatments showed a similar trend, while the eff ects were less prominent, but still suffi cient by managing fl uid-associated as well as infected wounds.

Abstract: Novel multifunctional bio-based nanofibrous mats were prepared which contain the commonly used pain reducing local anesthetic benzocaine (BZC) and the in situ pH-detecting dye bromocresol green (BCG). These can serve as a dual nano-carrier system for wound healing applications, especially in the treatment of infected wounds. BZC and BCG were introduced into cellulose acetate (CA) based nanofibers using a single-step needleless electrospinning process. The resulting CA nanofibers show a homogenous fiber diameter distribution around 600 nm, hydrophobicity with a water contact angle of 134°, and simultaneous porosities on the nano-micro- scale. In spite of their hydrophobic character, the nanofibrous mats showed a huge water absorption capacity (1657%), as well as good stability at physiological pH (negligible degradation). All the mentioned properties remain unchanged upon the inclusion of either BZC or BCG. Results from the in vitro drug release studies showed a pH dependent (i.e. controllable) release of BZC, and confirmed the expected maximum drug release rate at pH 9.0, which would correspond clinically to the pH of an infected wound. The accompanying color change of the nanofibrous mats, provided through the encapsulated BCG (from yellow to blue), is noticeable within a few seconds after the pH changes from acidic to alkaline. This rapid response of NSAID, together with the visible absorption of included dye, show the capacity of the proposed nanofibrous mats as an in situ pH-detecting system. Finally, the biocompatibility of the proposed nanofibrous mats was proven using human skin fibroblast cells, confirming their potential to be used in wound treatment.Graphical abstract: [ABSTRACT FROM AUTHOR]

Copyright of Tekstilec is the property of University of Ljubljana, Faculty of Natural Sciences & Engineering, Department of Textiles and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tekstilec is the property of University of Ljubljana, Faculty of Natural Sciences & Engineering, Department of Textiles and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of the present study was to prepare a polysaccharide (cellulose acetate) based nanofibrous sensor for detection of pH change in the wound environment. In order to prepare cellulose acetate (CA) nanofibers, acetic acid was used as a solvent, and fabrication of fibers was performed on the needle-less electrospinning apparatus. Long uniform CA nanofibers, with diameters ranging from 250 to 300 nm, were electrospun from 15 wt% CA and 85% acetic acid, with addition of halochromic dye (Bromocrezol Green). The addition of Bromocrezol Green in the spinning formulation did not affect the fiber formation. Prepared nanofibrous sensors were characterized using CIE color space analysis in order to evaluate the color due to pH change. Nanofibrous sensors exhibit yellow color when exposed to pH4 and lower, simulating the wound environment beneficial to the wound healing, and blue color when exposed to pH 9 and higher, simulating the environment that hampers wound healing (chronic, infected wounds). [ABSTRACT FROM AUTHOR]

Copyright of Tekstil: Journal of Textile & Clothing Technology is the property of Croatian Association of Textile Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The formation of endothelial cell monolayer on prosthetic implants has not sufficiently explored. The main reasons leading to the development of thrombosis and/or intimal hyperplasia is the lack of endothelialization. In the present work, we have studied the influence of oxygen and fluorine plasma treatment of polyethylene terephthalate (PET) polymers on human microvascular endothelial cell adhesion and proliferation. We characterized the polymer surface, wettability, and oxidation potential upon plasma treatment. Moreover, binding of serum and media compounds on PET surface was monitored by Quartz crystal microbalance method, X-ray photoelectron spectroscopy, and atomic force microscopy. Cell adhesion and morphology was assessed by light and scanning electron microscopy. The influence of plasma treatment on induction of cellular oxidative stress and cell proliferation was evaluated. The results obtained showed that treatment with oxygen plasma decreased the oxidation potential of the PET surface and revealed the highest affinity for binding of serum components. Accordingly, the cells reflected the best adhesion and morphological properties on oxygen-treated PET polymers. Moreover, treatment with oxygen plasma did not induce intracellular reactive oxygen species production while it stimulated endothelial cell proliferation by 25% suggesting the possible use of oxygen plasma treatment to enhance endothelialization of synthetic vascular grafts. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 2305-2314, 2014. [ABSTRACT FROM AUTHOR]

Non-woven viscose samples were treated for 5 min with non-equilibrium ammonia plasma. Plasma-induced properties often gradually change with time, thereby limiting the durability of surfaces for industrial application. The modified samples were stored for 10 and 30 days under air and argon, i.e. possible gases for maintaining plasma-gained absorption kinetics and biostatic activity. XPS results for the aged samples showed practically the same composition as for the freshly-treated samples, regardless of storage gases. Any aging of the plasma-induced hydrophilicity was not evident as the absorbency rate, capacity, and contact angles remained almost unchanged within one month, independent of the storage gases used. Biostatic activity endured almost unaltered over 10 days, whereas it decreased during 30 days, being more pronounced within argon than air. The results from absorption kinetics for both the saline solution and the synthetic exudate, as well as from microbiological analyses, revealed that the plasma-induced modifications of the non-woven material remained fairly unaltered for at least one month when stored within air, thus making this technique attractive for wound dressing applications. [ABSTRACT FROM PUBLISHER]

Viscose non-woven was treated by NH3 plasma. Different exposure times were used in order to find the optimum conditions for simultaneously improved hydrophilicity and antimicrobial activity, as desired effects by wound dressings. Both chemical and morphological modifications were studied by X-ray photoelectron spectroscopy and atomic force microscopy, respectively, revealing functionalization with nitrogen groups as well as formation of rich morphology at sub-micrometer scale. The wetting rise curves increased from 0.04 g2 s–1 for non-treated material to 1 g2 s−1 after prolonged treatment. The water contact angle decreased almost linearly with treatment time from 90° for non-treated samples to about 40° for samples treated for 140 s and remained rather constant thereafter. The AATCC 100–1999 standard test revealed reduction on all used bacteria, more pronounced for Gram-negative, that is, E. coli and P. aeruginosa, then for Gram-positive, that is, a significant for S. aureus and a marginal for E. faecalis. [ABSTRACT FROM PUBLISHER]

Abstract: Three industrially-prepared (via the sulphate synthesis process) and commercially-available nanoTiO2 colloidal suspensions were coated on polyester fabric using the conventional pad-dry-cure procedure, in order to enhance fabric functionalities by imparting self-cleaning and UV-protection ability. Various characterization techniques, i.e. transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), and UV/Vis spectroscopy of the suspensions revealed the presence of anatase TiO2 spherical-shaped nanoparticles of different crystallite sizes, as well as its prominent absorption capacity within the UV region. Scanning electron microscopy (SEM) was adopted to analyse the morphological structure of nanoTiO2-modified PES fabrics. Furthermore, the photocatalytic activity was investigated through the discolourations of red wine and red beet stains under two types of light sources, i.e. direct day light and artificial UV light, by means of a spectrophotometry. The UV-protective properties were also evaluated by calculating the ultraviolet protective factors of individual coated fabric. The obtained results show acceptable blocking properties against UV-rays, as well as the adequate self-cleaning abilities of TiO2-modified PES fabrics as governed by the types and concentrations of applied TiO2 suspension. [Copyright &y& Elsevier]

The aim of this research work was to study the surface properties and sorption characteristics of differently treated regenerated cellulose fabrics. Surface modifications of viscose, modal and lyocell samples caused by using standard chemical pre-treatment procedures were compared to an alternative activation procedure by applying low pressure oxygen plasma treatment. The elemental chemical composition of the modified fabric surfaces was investigated using X-ray photoelectron spectroscopy (XPS), while hydrophilic/hydrophobic properties were evaluated by determining the water contact angles, as well as thoroughly analysed using Owens–Wendt surface energy (SFE) and surface polarity investigations.Standard chemical and also plasma treatments changed the surface chemistry of cellulose. Bleaching and alkaline treatments increased the surface carboxylic acid content by approximately 4.8% while plasma treatment increased it by approximately 9.7%. As a consequence, higher hydrophilicity arises as proved by water contact angle decrease; i.e. 24% (61°) after standard chemical treatments and 70% (20°) after plasma treatment. Both chemical treatments increase the SFE and polar components, while the reduction of dispersive components was less pronounced. The oxygen activation treatment has the greatest influence on the SFEs of the samples as well as on polarity of the samples. [ABSTRACT FROM PUBLISHER]

Galactoglucomannans (GGMs) are water-soluble polysaccharides released and accumulated in process waters in the production of thermomechanical pulp. The general trend in the forestry industry is moving towards bio-refineries, for example utilizing these hemicelluloses as bioactive substances. At present, there is no industrial use of wood-derived mannans. In this study, GGMs extracted from thermomechanical pulp, as well as further carboxymethyl-ated galactoglucomannans (CM-GGMs), were sulfated to increase their antithrombotic properties. The products were characterized with Fourier transform infrared spectroscopy, nuclear magnetic resonance and capillary electrophoresis. The carbohydrate composition and sulfur amounts were determined. The products' total charges were determined by polyelectrolyte titrations and their antithrombotic effect was measured based on the activated partial thromboplastin time. The results showed a significant increase in the antithrombotic effect of the sulfated galactoglucomannans from spruce wood and thus a potential new use for wood-derived mannans. [ABSTRACT FROM AUTHOR]

The aim of this study was to setup a method for detection and quantification of monosaccharide components in technical galactoglucomannas (T-GGM) from spruce wood using capillary zone electrophoresis (CZE). CZE technique was optimised regarding borate buffer concentrations, EOF modifier application, and system pH. Aqueous solution of T-GGM was chemically hydrolysed by sulphuric acid, in an autoclave. In this way obtained monosaccharides were derivatized with 4-amino benzoic acid ethyl ester via reductive amination using sodium cyanoborohydride. The results of the optimisation procedure showed that the borate buffers at lowest concentrations (100 and 200 mM) with acetonitrile addition as EOF modifier gave the optimal measurement results, as it showed sufficient separation at relatively short migration times. The amounts of single monosaccharide components in the T-GGM samples obtained by the optimised CZE procedure were practically the same in comparison to the results of the well established HPLC-anion exchange chromatography. On the basis of this research, it was concluded that the capillary zone electrophoresis is an efficient analytical procedure for the characterisation of galactoglucomannans derived from softwoods. [ABSTRACT FROM AUTHOR]

The article deals with a study which prepared nanocomposite fibers based on polypropylene (PP) polymer with different content of nanofiller. In preparing PP nanocomposite fibers, montmorillonite modified by N,N-di-methyl-N,N dioctadecylammonium cations was employed. It was noted that the zeta potential (ZP) value of nanofilled fibers was affected by the addition of nanoparticles. Meanwhile, the different concentrations of nanofiller have no significant impact on isoelectric point (IEP).

Copyright of Tekstil: Journal of Textile & Clothing Technology is the property of Croatian Association of Textile Engineers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This research investigates the optimal process of viscose fabric crosslinking with a low formaldehyde emitting agent (modified - N-methylol-dihydroxyethylene urea (Ruco Fan) using statistical 3-factor analysis. The influences of different concentrations of crosslinking agents, catalysts and softening agents were evaluated regarding viscose fabric mechanical changes, colour change and swelling ability after crosslinking. The following methods were used for this purpose: determination of wrinkle recovery angle, determination of breaking force together with an elongation, colour change, and the viscose fiber's swelling ability. Results showed that after crosslinking, the wrinkle recovery angle and the breaking force increased or stayed at the same level, while in the case of elongation and swelling ability, the opposite trend was seen. Colour difference was negligible for the treated viscose fabric. The result of factor planning is the optimal finishing recipe which includes the least possible use of chemicals. [ABSTRACT FROM AUTHOR]

Modification and functionalization of polymer surface properties is desired in numerous applications, and a standard technique is a treatment with non-equilibrium gaseous plasma. Fluorinated polymers exhibit specific properties and are regarded as difficult to functionalize with polar functional groups. Plasma methods for functionalization of polyvinylidene fluoride (PVDF) are reviewed and different mechanisms involved in the surface modification are presented and explained by the interaction of various reactive species and far ultraviolet radiation. Most authors used argon plasma but reported various results. The discrepancy between the reported results is explained by peculiarities of the experimental systems and illustrated by three mechanisms. More versatile reaction mechanisms were reported by authors who used oxygen plasma for surface modification of PVDF, while plasma sustained in other gases was rarely used. The results reported by various authors are analyzed, and correlations are drawn where feasible. The processing parameters reported by different authors were the gas pressure and purity, the discharge configuration and power, while the surface finish was predominantly determined by X-ray photoelectron spectroscopy (XPS) and static water contact angle (WCA). A reasonably good correlation was found between the surface wettability as probed by WCA and the oxygen concentration as probed by XPS, but there is hardly any correlation between the discharge parameters and the wettability. [ABSTRACT FROM AUTHOR]

Starch is the second most abundantly available natural polymer in the world, after cellulose. If we add its biodegradability and non-toxicity to the natural environment, it becomes a raw material very attractive for the food and non-food industries. However, in the latter case, mainly due to the high hydrophilicity of starch, it is necessary to carry out many more or less complex operations and processes. One of the fastest growing industries in the last decade is the processing of biodegradable materials for packaging purposes. This is mainly due to awareness of producers and consumers about the dangers of unlimited production and the use of non-degradable petroleum polymers. Therefore, in the present review, an attempt was made to show the possibilities and limitations of using starch as a packaging material. The most important physicochemical features of this biopolymer are discussed, and special attention is paid to more or less environmentally friendly methods of improving its processing properties. [ABSTRACT FROM AUTHOR]

Several naturally occurring biological systems, such as bones, nacre or wood, display hierarchical architectures with a central role of the nanostructuration that allows reaching amazing properties such as high strength and toughness. Developing such architectures in man-made materials is highly challenging, and recent research relies on this concept of hierarchical structures to design high-performance composite materials. This review deals more specifically with the development of hierarchical fibres by the deposition of nano-objects at their surface to tailor the fibre/matrix interphase in (bio)composites. Fully synthetic hierarchical fibre reinforced composites are described, and the potential of hierarchical fibres is discussed for the development of sustainable biocomposite materials with enhanced structural performance. Based on various surface, microstructural and mechanical characterizations, this review highlights that nano-objects coated on natural fibres (carbon nanotubes, ZnO nanowires, nanocelluloses) can improve the load transfer and interfacial adhesion between the matrix and the fibres, and the resulting mechanical performances of biocomposites. Indeed, the surface topography of the fibres is modified with higher roughness and specific surface area, implying increased mechanical interlocking with the matrix. As a result, the interfacial shear strength (IFSS) between fibres and polymer matrices is enhanced, and failure mechanisms can be modified with a crack propagation occurring through a zig-zag path along interphases. [ABSTRACT FROM AUTHOR]

Hyaluronic acid (HA), a high-molecular-weight linear polysaccharide, restricts solute transport through the interstitial space. Albumin and hydroxyethyl starch (HES) solutions are used to correct the decrease of blood volume during surgery, but may leak into the interstitial space under inflammation conditions. Given the possibility that the structure of HA may be affected by adjacent macromolecules, this study tested whether albumin and HES (Mw 130,000) exert different effects on solute permeation through sodium hyaluronic acid (NaHA: Mw 1.3 × 106) solution. To this end, permeation of Orange G, a synthetic azo dye (Mw 452), into NaHA solutions containing albumin or HES over time was assessed. The amount of time it took for the relative absorbance of Orange G to reach 0.3 (T0.3) was determined in each NaHA solution relative to the reference solution (i.e., colloid solution without NaHA). Relative T0.3 values of albumin were larger than those of HES for 0.1% NaHA solution (3.33 ± 0.69 vs. 1.16 ± 0.08, p = 0.006, n = 3) and 0.2% NaHA solution (1.95 ± 0.32 vs. 0.92 ± 0.27, p = 0.013, n = 3). This finding may help in the selection of an appropriate colloid solution to control drug delivery into the interstitial space of cancer tissue under inflammation conditions. [ABSTRACT FROM AUTHOR]

Abstract: An alternative route to lower the flammability of viscose fibres is presented. Instead of adding a flame retardant to the viscose dope chemically, we have grown a layer of silica (SiO2) on the surface of a regenerated cellulose fibre via a sol–gel process. One set of samples was used as-received, while the other was pre-treated in an 18% NaOH solution, giving a rough, etched surface to the fibre. The different surface morphology of both fibre types triggered a different growth of silica layers. On an untreated fibre, silica formed a 300–400nm thick surface layer containing a high density of cracks and holes. Conversely, on a NaOH pre-treated fibre, the silica layer intruded into fibre interior, adhered more tightly to the fibre structure and formed an almost defect-free, thin (100nm) layer on the outer fibre surface. This type of silica layer increased the temperature at which the fibre started to decompose by 20°C. It also hindered significantly the flow of oxygen to the generated volatiles during the thermal decomposition, and increased the temperature of glowing combustion of the residual char; the temperature of the corresponding exothermic peaks increased by ca. 20°C and 40°C. In contrast, the thermal effects of silica coatings that grew on an untreated fibre were much smaller. [Copyright &y& Elsevier]