Aysin Dural Erem

Antibacterial activity of PA6/ZnO nanocomposite fibers

In this study, ZnO-loaded PA6 nanocomposite preparation and its antibacterial activity are investigated. This work aims to study the effect of the sizes and amount of the ZnO nanofiller on the antibacterial, mechanical, and thermal properties of the PA6/ZnO nanocomposites. The melt intercalation method is applied to prepare polyamide 6 (PA6) nanocomposite fibers, including 0, 0.5, 1, 3, 5 wt % zinc oxide (ZnO), using a laboratory-scale compounder. The antibacterial activity of the fibers against Staphylococcus aureus (ATCC 6538) as a gram positive bacterium and Klebsiella pneumoniae (ATCC 4352) as a gram negative bacterium is determined according to ASTM E 2149-0. Mechanical and thermal characterization tests are performed according to relevant standards (ASTM D7426-08, ASTM E1131-08, ASTM D3822-07; DSC, TGA, tensile tests). It is found that the dispersion of the ZnO particles within the PA6 matrix is homogenous according to scanning electron microscopy results. Antibacterial activity tests show that PA6/ZnO nanocomposite fibers exhibit antibacterial efficiency related to their nanoparticle contents. An increase in the amount of nanoparticles causes an increase of the antibacterial activity of the fibers. On the other hand, mechanical and thermal characterization tests show that the addition of ZnO nanoparticles does not affect the strength and thermal properties of the nanocomposites for these loadings.

Antimicrobial activity of poly(l-lactide acid)/silver nanocomposite fibers

Silver (Ag) nanoparticles (NP) and poly(lactide acid) (PLA) granules were microcompounded to form a nanocomposite. A series of PLA nanocomposite fibers containing, respectively, 0, 0.5, 1, 3 or 5 wt% Ag were produced and their antimicrobial activity against Gram-negative and Gram-positive bacteria evaluated. It was found that the PLA/Ag nanocomposite fibers exhibited increased antimicrobial activity, depending on the filler content. On the other hand, mechanical and thermal characterization tests, including thermogravimetric analysis, differential scanning calorimetry and tensile testing, showed that increasing concentrations of Ag hindered the mechanical properties of Nanocomposites due to partial agglomeration, leading to the generation of flaws. The crystallinity of the fibers was found to decrease by about 23% if the Ag content was increased to 5%. This could be attributed to a more rapid cooling rate resulting from the high thermal conductivity of the Ag particles.

In vitro assessment of antimicrobial polypropylene/zinc oxide nanocomposite fibers

A series of polypropylene (PP) nanocomposite fibres containing respectively 0, 0.5, 1, 3, and 5 wt% ZnO nanoparticles (NPs) were prepared by melt spinning. The antimicrobial activity of these fibers against Staphylococcus aureus (ATCC 6538) as a Gram-positive bacterium and Klebsiella pneumoniae (ATCC 4352) as a Gram-negative bacterium was evaluated. It was confirmed by scanning electron microscopy that the dispersion of the NPs within the PP matrix was homogeneous. Although such homogeneity the fibers are unable to exhibit antimicrobial activity. The absorption properties of the fibers was then investigated and found to be inadequate, so cold plasma and chemical finishing were applied to improve their absorptivity. After this treatment the PP/ZnO nanocomposite fibers exhibited increasing antimicrobial effectiveness with filler content. In addition, mechanical and thermal characterization tests showed that increasing concentration of ZnO–NPs improved the mechanical properties of the fiber due to the interface between the matrix and the nanoparticles sharing the stress. The crystallinity of the fibers was found to decrease by about 7% as the level of ZnO increased to 5%. This was attributed to the more rapid cooling experienced in the presence of ZnO particles of high thermal conductivity.

In vitro assesment of antimicrobial activity and characteristics of polyamide 6/silver nanocomposite fibers

In this study, the preparation method and characteristics of silver (Ag) nanoparticle (NP) loaded polyamide 6 (PA6) nanocomposite and its antimicrobial activity against Klebsiella pneumonia and Staphylococcus aureus were investigated. The melt intercalation method was used to prepare a series of PA 6 nanocomposite fibers containing, 0; 1; 3; 5 % (wt.) Ag. PA6/Ag nanocomposite fibers exhibit increased antimicrobial efficiency with the increase of nanoparticle contents. On the other hand, thermal characterization tests show that the increased concentration of Ag nanoparticles reduces the mechanical properties due to their partial agglomeration leading to flaw generation. The crystallinity of the fibers was found to decrease about 10 % with increase of Ag to 5 %. This was attributed to faster cooling rate experienced in the presence of high thermal conductivity Ag particles.

Polimer Esaslı Nanokompozitler ve Tekstil Uygulamaları

Production and use of nanocomposites increased with the development of nanotechnology. Polymer nanocomposites are the most widely used nanocomposite types. They are obtained by mixing polymer melt and nano fillers such as fibers particles and tubes. With the use of polymer nanocomposites, it is possible to produce more strong, durable and functional products. With the use of nanocomposites in the textile industry, textile products with antimicrobial, UV-resistant, high-strength, electrically conductive, dirt-resistant properties has been able to produce. In this study, nano materials used in the production of nanocomposite will be introduced and their effects on the nanocomposites will be discussed. Also by comparing the production methods of nanocomposites, the production methods will be explained how to alter application areas of nanocomposites.

Polipropilen/Titanyum Dioksit Nanokompozit Liflerin Üretimi ve Karakterizasyonu

Nanotechnology has become one of the most popular research areas of all technical disciplines. In most of the nanotechnology applications, polymeric matrixes are used as the dispersion medium for the nanoparticles. In this study, TiO2 loaded PP nanocomposite fibers preparation and their properties are investigated. The melt spinning method is applied to prepare nanocomposite fibers, including 0, 0.5, 1, 3, 5 wt % filler content, using a laboratory-scale twin screw micro-compounder (DSM Xplore). While the thermal properties of the obtained fibers were determined by using differential scanning calorimeter (DSC) and thermal gravimetric analysis (TGA) methods, crystalline structure of the samples were determined via X-ray diffarctometer (XRD). Morphology and mechanical properties of fibers were assigned with scanning electron microscopy (SEM) and tensile tests. Depend on X-ray diffraction results; they have semi crystalline structure and α-phase crystal structure. With addition of nanoparticles, the tensile properties of the samples increased. In our opinion these nanocomposite fibers can be used in technical and medical applications, such as sutures, wound dressings, meshes, bandage, hospital clothes, water filters, gas filters, floor and wall coversNanotechnology has become one of the most popular research areas of all technical disciplines. In most of the nanotechnology applications, polymeric matrixes are used as the dispersion medium for the nanoparticles. In this study, TiO2 loaded PP nanocomposite fibers preparation and their properties are investigated. The melt spinning method is applied to prepare nanocomposite fibers, including 0, 0.5, 1, 3, 5 wt % filler content, using a laboratory-scale twin screw micro-compounder (DSM Xplore). While the thermal properties of the obtained fibers were determined by using differential scanning calorimeter (DSC) and thermal gravimetric analysis (TGA) methods, crystalline structure of the samples were determined via X-ray diffarctometer (XRD). Morphology and mechanical properties of fibers were assigned with scanning electron microscopy (SEM) and tensile tests. Depend on X-ray diffraction results; they have semi crystalline structure and α-phase crystal structure. With addition of nanoparticles, the tensile properties of the samples increased. In our opinion these nanocomposite fibers can be used in technical and medical applications, such as sutures, wound dressings, meshes, bandage, hospital clothes, water filters, gas filters, floor and wall covers.