Necdet Seventekin

The Damage Caused by Micro-organisms to Cotton Fabrics

A study is reported in which the damage caused by micro-organisms to 100% cotton material under different conditions and the level of this damage when different finishing materials were used were investigated. The damage caused by Aspergillus niger, used as the experimental organism for 100% cotton material, was seen as a decrease in the tensile strength with time; the temperature, pH, and change in conditions of the medium are shown to affect the decrease in the tensile strength. The microbial growths were differentially inhibited by seven finishing materials which were imparted, but most of them were removed by washing.

Evaluation of some of the physical properties of atmospheric plasma treated polypropylene fabric

In this study, atmospheric pressure plasma (APP) treatment was applied to polypropylene (PP) fabric with non‐polymerizing gases, such as air, argon, and nitrogen. Properties of the APP‐treated samples including low‐stress mechanical behavior, air permeability, water vapor permeability, and thermal characteristics were evaluated. Tensile and friction coefficient of the specimens were also measured. The changes in these properties are believed to be closely related to the inter‐fiber and inter‐yarn frictional force induced by the APP. The decrease in the air permeability of the APP‐treated PP fabric was probably because of the plasma action effect on change in fabric surface morphology, which was confirmed by scanning electron microscopy micrographs. The change in the thermal properties of the APP‐treated PP fabric was in good agreement with the earlier findings and can be attributed to the amount of air trapped between the yarns and fibers. This study suggests that the APP treatment can influence the final properties of the PP fabric, and also provides information for developing APP‐treated PP fabric for industrial use.

Effect of Surrounded Air Atmospheric Plasma Treatment on Polypropylene Dyeability Using Cationic Dyestuffs

The dyeing properties of the polypropylene (PP) fabrics using cationic dyestuffs were investigated after surrounded air atmospheric cold-plasma treatment. Surrounded air plasma (SAP) was used to modify fabric surface and to optimize the effects of some discharge parameters on dyeability. Surface morphology and physical-chemical properties of plasma treated fibers were also characterized by Fourier transform infrared attenuated total reflection spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. Activated surfaces by SAP were grafted with different compounds: 6-aminohexanoic acid, acrylic acid, and hexamethyldisiloxane. Dyeing the plasma-induced grafted PP fabric with basic dye was quite satisfactory when high color strength and good fasteness were considered.

Structural coloration of chitosan-cationized cotton fabric using photonic crystals

In this work, poly (styrene-methyl methacrylate-acrylic acid) P(St-MMA-AA) composite nanospheres were deposited onto chitosan-cationized woven cotton fabrics followed by a second layer of chitosan. The deposited photonic crystals (PCs) on the fabrics were evaluated for coating efficiency and resistance, chemical analysis and color variation by optical and SEM microscopy, ATR-FTIR, diffuse reflectance spectroscopy and washing fastness. Chitosan deposition on cotton fabric provided cationic groups on the fiber surface promoting electrostatic interaction with photonic crystals. SEM images of the washed samples indicate that the PCs are firmly coated on the cotton surface only in the chitosan treated sample. The photonic nanospheres show an average diameter of 280 nm and display a face-centered cubic closepacking structure with an average thickness of 10 μm. A further chitosan post-treatment enhances color yield of the samples due to the chitosan transparent covering layer that induce bright reflections where the angles of incidence and reflection are the same. After washing, no photonic crystal can be detected on control fabric surface. However, the sample that received a chitosan post-treatment showed a good washing fastness maintaining a reasonable degree of iridescence. Chitosan fills the spaces between the polymer spheres in the matrix stabilizing the photonic structure. Sizeable variations in lattice spacing will allow color variations using more flexible non-close-packed photonic crystal arrays in chitosan hydrogels matrices.

Structural coloration of chitosan coated cellulose fabrics by electrostatic self-assembled poly (styrene-methyl methacrylate-acrylic acid) photonic crystals

The structural coloration of a chitosan-coated woven cotton fabric obtained by glutaraldehyde-stabilized deposition of electrostatic self-assembled monodisperse and spherically uniform (250 nm) poly (styrene-methyl methacrylate-acrylic acid) photonic crystal nanospheres (P(St-MMA-AA)) was investigated. Bright iridescent coatings displaying different colors in function of the viewing angle were obtained. The SEM, diffuse reflectance spectroscopy, TGA, DSC and FTIR analyses confirm the presence of structural color and the glutaraldehyde and chitosan ability to provide durable chemical bonding between cotton fabric and photonic crystal (PCs) coating with the highest degradation temperature and the lowest enthalpy. The coatings are characterized by a mixture of face-centered cubic and hexagonal close-packed arrays alternating random packing regions. For the first time a cost-efficient structural coloration with high washing and light fastness using self-assembled P(St-MMA-AA) photonic crystals was successfully developed onto woven cotton fabric using chitosan and/or glutaraldehyde as stabilizing agent opening new strategies for the development of dye-free coloration of textiles.

Dyed Poly(styrene-methyl Methacrylate-acrylic Acid) Photonic Nanocrystals for Enhanced Structural Color

In the present work, we investigated the combined effect of poly(styrene-methyl methacrylate-acrylic acid) [P(St-MMA-AA)] PCs with the disperse dye C.I. Disperse Red 343 on the photonic crystals (PCs) shape, distribution, organization, iridescence, chemical structure, thermal stability, and reflectance. PCs were successfully produced in the form of highly spherical, monodisperse colloidal structures. Presence of dye in the PCs inner core-shell structure was confirmed via Fourier-transformed infrared spectroscopy. The PCs brightness and iridescent effect was enhanced by the presence of the dyestuff, which also promoted the self-assembly of the colloidal nanospheres in the form of arrays. The P(St-MMA-AA) PCs thermal stability did not alter with the introduction of the dye. In a side experiment, dyed PCs were also coated onto dyed polyamide fabrics. Data reported successful coating of the textile fabric and an improvement of its reflectance. Fabric immobilization fostered the self-assembling of the dyed colloidal nanospheres in the form of well-organized face-centered cubic, closed-packed arrays. This is the simplest and most energy favorable organization for PCs. The combination of disperse dyes with PCs is a very recent and challenging idea and could open new ways to understand the influence the PCs photonic-band structure may exert on the photoluminescence properties of the dyes embedded in the PCs inner space, and vice versa.

Pamuklu Kumaşlarda Antibakteriyel Bitim İşlemi için Atmosferik Plazma ve Kimyasal İşlemlerin Kombinasyonu

Bu calismanin amaci, triklosan esasli kimyasal ile siklodekstrin esasli ticari urun birlesimin plazma modifikasyonu yapilarak ve yapilmayarak pamuklu kumaslara baglanmasinin incelenmesidir. Islem goren numuneler SEM analizi ile karakterize edilmistir. Yikanmis ve yikanmamis kumaslarin antibakteriyel aktiviteleri AATCC Test Metot 147-1998’e gore degerlendirilmis ve numunelerin bazi fiziksel ozellikleri de incelenmistir. Triklosan, siklodekstrin ve atmosferik plazma kombinasyonu ile pamuklu kumaslarin antibakteriyel aktivitesini 60°C’de 5 yikamaya kadar korudugu gozlenmistir.