Abstract: This paper focuses on the thermal and mechanical behavior of fiber-reinforced bio-epoxy materials in which the bio-content has been varied from 0 up to 100 %. Assorted formulations based on standard epoxy resin and epoxidized plant oil with varying bio-hardeners in differing matrix formulations, filler contents and fibers were used. DSC, TGA, DMA and HDT tests were carried out, as well as tensile and Charpy impact tests. The results show possible technical applications for bio-based epoxy materials.
Abstract: Polymethylmethacrylated oligoaniline was synthesized by methylmethacrylate radical polymerization in the presence of oligoaniline. By means of IR-spectroscopy polymethylmethacrylated oligoaniline was characterized and its degree of oxidation was showed to be conserved. With the use of cyclic voltammetry its electroactivity was found to be preserved after modification.
Abstract: Successful results of textile materials finishing process in order to gain desired properties to the fabric according to customers’ demands mainly depend on properly-carried pre-treatment stages. The present study covers twill weave cotton/polyester fabric’s modification in alkaline medium at different temperatures and treatment durations through exhaustion (hot and cold treatment) and pad-steam process. An influence of the reduction agent addition was ascertained. Weight loss, water absorbency, vertical wicking, dye uptake, colour measurements, surface morphology and psysicomechanical characteristics were determined. Samples and recommendations of optimal alkaline treatment technologies are developed.
Abstract: Polyisocyanurate foams incorporating polyols derived from rapeseed oil are developed, with the polyol system comprising up to 80% of rapeseed oil esters. To enhance the mechanical characteristics and fire resistance of the foams, they are filled with three different types of organically modified clay (organoclay) in the range of loading from 1 to 5% by weight. Marked increase in tensile stiffness of nanocomposite foams is observed.
Abstract: Hygroscopicity, moisture return, wetting, capillarity and water vapour permeability of materials were studied in shoes linings and insoles made of natural and artificial leather. It was established that liquid-based and final finishing deteriorate hygienic properties of natural leather to a great extend. With the use of obtained results, a new graphically-numerical method was tested in assessment of shoe material comfortability, the materials that have direct contact with the human foot. According to the method, the ratio between pentagon areas of material tested and reference material is taken as quantitative indicator of quality.
Abstract: Homopolymer PHB and copolymer PHB/HV containing granules were isolated from Azotobacter chroococcum cells and used for latexes formation. Composite latex films were formed from the PHB and PHB/HV latexes with different content of poly (vinyl alcohol) and glycerol and a hydrophobic fluorescent benzanthrone derivated dye 3-piperidinobenzanthrone, possessed high fluorescence intensity in a system with PHA granules. Fluorescence based methods were used for characterization of the elaborated latex film by their stability at high temperature and for visualization of the film surfaces PHA granules distribution. Film stability in phosphate buffered saline was evaluated by dye migration activity in the solution. The results of mechanical testing of the latex films were compared with the stability testing and surface visualization results. The data obtained allow a better understanding the difference of the mechanical and physical properties of the investigated films.
Abstract: This paper is about investigation of the bio-based polyurethanes from the rapeseed oil polyols and their modification with montmorillonite nanoparticles. The results of hardness and tensile properties investigation of polyurethane / montmorillonite nanocomposites are presented.
Abstract: Post-consumer polycarbonate (RPC) blends with various amounts (5, 10, 30 wt. %) of ethylene vinyl acetate copolymer (EVAc) are investigated as potential nanocomposite matrices. At EVAc weight content of 10 wt.% maximum tensile strength σM and impact strength AI increase is observed in comparison to neat RPC. Addition of EVAc, however, reduces resistance to creep as well as decrease thermal stability of the investigated compositions. Addition of montmorillonite nanoclay (MMT), however, allows increase modulus of elasticity E and yield strength σY of the investigated RPC blend with 10 wt. % of EVAc. Besides it creep resistance and thermal resistance of the investigated system is increased to certain extent.
Abstract: Electrochemical properties and possibilities of manufacturing the anodes based on water-soluble binders such as carboxymethylcellulose (CMC) have been investigated in order to create prerequisites for development of “green” technologies for recyclability of LIBs components. In this work an advanced anode was designed. A kind of nanosized carbon coated Si composite was synthesized. The charge/discharge test reveals that the advanced anode shows a reversible capacity of 600 mAh/g. The improved performance was ascribed to the carbon shell of Si and CMC binder. The binder CMC buffers the expansion of the Si and the improved electric contact between the active material and copper current collector.