In the presentation biocompatible nano-composites with a layer of hydroxyapatite on the textile surface were prepared. A nonwoven textile based on regenerated cellulose fibres was used. Before the procedure of nano-modification, textile surface was activated by alkaline and plasma pre-treatment, respectively. The influence of pre-treatment procedure on nano-coating formation was studied. By the activation a homogeneous layer of particles on cellulose fibres was formed, however plasma treated fibres formed a more uniform nano-particles layer.
COBISS.SI-ID: 16346134
Due to increasing quantities of waste organic compounds in the environment more efficient adsorbents are needed. Recently clays are widely used for the adsorption and removal of organic pollutants due to their high specific surface area and because clays are natural environmental-friendly materials. Usually clay minerals are applied as dispersed adsorbents when used for water purification. To avoid the problem of removing clays from clean purified water, which is very difficult, nanocomposite clay/polymer hydrogels are used. Therefore, this review is focused on preparation and characterization methods of nanocomposite clay/polymer hydrogels used for adsorption of dyes. Structures and functionalities of nanocomposites are described and conditions (e.g. clay particle type and concentration, dispersing medium, monomer, cross-linker concentrations, and drying procedure, etc.) for achieving exfoliated and intercalated clay – hydrogel structures are discussed. In addition to functional properties of nanocomposites conditioned by the nanocomposite preparation process are studied.
COBISS.SI-ID: 16321046
Our research was focused on the preparation of three component nanocomposite pore-filled membrane composed of a soft hydrogel, nanoparticles and microporous substrate. In-situ polymerization of nanocomposite hydrogels inside the PP membrane pores represents a useful method, which yields nanocomposite membrane with exceedingly improved filtration properties. For achieving a full coverage of polypropylene membrane pores with nanocomposite hydrogel, we used different wetting agents and methods. Optimal procedure was studied by measuring the amount of hydrogel in the membrane and hydrophilic/hydrophobic character of the membrane. Filtration efficiency of the new composite membrane was defined using an ultrafiltration cell. Decolouration degree of acid dye C.I. Acid Orange 33 solution was determined using UV/VIS spectroscopy.
COBISS.SI-ID: 16097558
A review of some untraditional fibres is given in the paper. Technical fibres are mainly obtained with fibre isolation, which means that cellulose fibres are multicellular structures with individual cells bound into fibre bundles. Different retting processes can be performed in both acid and alkaline mediums, respectively, and with an enzymatic treatment. The used procedure influences the fibre surface morphology. Some biofibres from agricultural by-products, e.g. wheat straw, pineapple leaves, sugarcane bagasse, hop stems, Musaceae plants, quinoa etc are introduced. In addition, the fibres from different grass and legume species and from sea grass are presented in the article.
COBISS.SI-ID: 16561942
An in situ technique for preparing composite nanoparticles from hydrophobic cellulose acetate and hydrophilic polysaccharides using nanoprecipitation is presented. This technique allows the nanoparticlesć surface properties to be tuned very specifically. Spherical, narrow-size-distributed composite nanoparticles of different size, charge, functionality, and increased stability can be generated by using hydroxyethyl cellulose, carboxymethyl cellulose, low molecular weight chitosan, and amino cellulose. The influence of the pH and hydrophilic polysaccharide content in the particle formation is shown. The pH- and ionic strength- effective zeta-potential functions are evidence of the presence of functional polysaccharides at the nanoparticle surface. The in situ technique is compared with the adsorption of hydrophilic polysaccharides onto cellulose acetate nanoparticles in two steps. The great potential of in situ prepared composite nanoparticles in the pharmaceutical industry and bio- or food technology, as carriers of hydrophobic substances in aqueous media and for specific surface modifications, e.g., to selectively introduce strong antimicrobial properties, is illustrated.
COBISS.SI-ID: 15778070