Wieslawa Urbaniak-Domagala

The Use of the Spectrometric Technique FTIR-ATR to Examine the Polymers Surface

The development of material engineering is accompanied by a growing demand for routine, nondestructive techniques for material and product testing. These techniques are to be used for the assessment of chemical and physical structure of new materials as well as for a systematic control of their manufacturing processes. Nowadays nanotechnologies fulfill a particular role in creating new materials of nanometric dimensions. The products of nanotechnology are made in various forms, mostly such as coatings and fibers. Coatings are of great practical importance while deposited on conventional substrates, such as metals, ceramics and polymers to impart new functions, e.g. anticorrosive, reflexive, sensory properties, etc., to them. Coatings are mostly made of polymers and hence their functional properties and durability mainly depend on polymer chemical and supermolecular structure. The current control tests of the chemical properties and supermolecular characteristic of materials are carried out with the use of IR absorption spectroscopy. Currently, these are dedicated to test the surface of materials. This paper concerns the spectroscopic technique FTIR used to test the surface of polymeric materials and coatings formed on polymeric substrates. The general characteristics, advantages and drawbacks of this technique in testing polymer surfaces have been presented.

The method of solid-liquid contact angle measurement using the images of sessile drops with shadows on substratum

This paper presents the method of liquid-solid contact angle measurement for the images of sessile droplets, including drop shadows on substratum materials, instead of usual horizontal bottom level lines. ADSA-P trajectory and its skew projection are used to approximate drop profile and shadow boundaries respectively. The intersections of both trajectories determine contact points and localize the bottom line. This implies contact angles between the bottom and profile trajectory.

Chitin filaments from dibutyrylchitin precursor: Fine structure and physical and physicochemical properties

Chitin filaments obtained after alkaline hydrolysis of dibutyrylchitin ( DBCH ) precursor filaments were investigated. The morphological structure, fine structure, and selected physical and physicochemical properties were studied. The studies of morphological structure included the assessment of the cross-section profile, the length and developing index of the contour line of the cross sections, the appearance of spherolitical crystalline aggregations, and the existence of skin-core building. The appraisal of the fine structure comprised the recognition of the lattice crystal system and the parameters of the unit cell, the crystallinity degree and average lateral crystallite sizes, and the crystalline and amorphous orientation. The characterization of physical properties included the appraisal of density, mechanical, thermal, electrical, and optical properties. In the area of physicochemical properties, swelling and dyeability were examined.

The surface modification of ballistic textiles using plasma-assisted chemical vapor deposition (PACVD)

This paper describes studies on the surface modification of so-called ballistic materials (materials commonly used to protect the human body against firearms, i.e. fragments or bullets). Two materials, an ultra-high molecular weight polyethylene (UHMWPE) composite and aramid fabric, were investigated. The surfaces of these fibrous materials were modified using plasma-assisted chemical vapor deposition (PACVD) to examine the effects of the modification on the material properties, which are important for designing ballistic protections. Accordingly, both the mechanical strength and water resistance of the modified materials were tested. The results clearly show the impact of the modification on both parameters.

Plasma modification of polylactide nonwovens for dressing and sanitary applications

Polylactide (PLA) non-woven surfaces were modified with Radio Frequency plasma (RF) under reduced pressure with the use of two media, air and C6F14 vapor. The effectiveness of the plasma modification of nonwovens was analyzed by examining the fiber surface layer with ATR-FTIR absorption spectroscopy, SEM/EDX microanalysis of atomic composition, SEM surface morphology, wettability tests, susceptibility to water, and physiological liquid absorption tests and air permeability tests. The type of plasma used determines the effect obtained. Air plasma improves sorption properties of nonwovens and does not significantly affect air permeability. C6F14 vapor plasma significantly reduces the absorption of liquids by the fabric and increases its hydrophobicity. The effects obtained from the plasma are stable for six months of fabrics storage after treatment. PLA fabrics modified with plasma can be used for various applications such as dressing and sanitary materials.

Structural Changes in Fibrous Ballistic Materials During PACVD Modification

During PACVD Modification. FIBRES & TEXTILES in Eastern Europe 2015; 23, 6(114): 102-115. DOI: 10.5604/12303666.1167426 102 Researches focused on improving the adhesion of UHMWPE fibres with resin or low-molecular polyethylene forming the destination matrix of the final ballistic material, inter alia by increasing the surface energy. This enables better and more durable blending of modified fibres with the matrix material [4 12]. The effect of plasma assisted chemical vapour deposition (PACVD) polymer deposition onto textile ballistic materials on the physicalmechanical behaviour was described in detail in [4, 13]. ,5,6,7,8,9,10,11,12 The aim of the research was to optimise PACVD modification of two types of unpurified technical textile materials: p-aramid fabric and UHMPWE fibrous materials, to directly obtain a functionalized surface with a highly reproductive deposited polymer.

Development Trends in Electronics Printed: Intelligent Textiles Produced with the Use of Printing Techniques on Textile Substrates

The authors concentrated their attention on the new area of research, concerning properties of electrically conductive textiles, produced by printing techniques. Such materials can be used for monitoring, for example, the rhythm of breathing. The aim of this study was to develop a sensor of strains for the needs of wearable electronics. A resistance‐type sensor was made on a knitted fabric with shape memory, dedicated to monitor motor activity of human. The Weftloc knitted fabric shows elastic memory—thanks to the presence of elastomeric fibers. The dependence of sensoric properties of the Weftloc knitted fabric on the values of load, its increment rate, and its direction of action was tested. Mechanical parameters including total and elastic strain, elasticity degree, and strength were also assessed. The results indicate an anisotropic character of mechanical and sensoric behaviors of the sensor showing a particularly optimal behavior during diagonal loading. Electro‐conductive properties have been imparted to the Weftloc fabric by chemical deposition of polypyrrole dopped with Cl ions. In addition, authors used as a carrier functional water dispersion of carbon nanotubes AquaCyl that was adapted in the Department of Material and Commodity Sciences and Textile Metrology for forming electrically conductive pathways by film printing method. It was assumed that the electrically conductive paths are sensitive to chemical stimuli. Studies of the effective‐ ness of the sensors for chemical stimuli were conducted for selected pairs of liquids. The best sensory properties were obtained for the methanol vapor—the relative resistance (Rrel.) at the level above 40%. In the case of nonpolar liquid vapor, the sensoric sensitivi‐ ty of the printed fabric was much lower, with Rrel. level below 29%. Properties of the electrically conductive materials, such as thermal conductivity, electrical conductivity, and resistance to chemicals, allow for widely using them nanotechnology.

Deposition of polypyrrole insulating layer on copper monofilaments using low temperature plasma technique

Abstract Polypyrrole is a material with growing application in technique and medicine. It characterises with thermal durability, environmental resistance, and biocompatibility, electric conductivity regulated in wide range by using of dopants. In the following research plasma RF 13·56 MHz type H was used to obtained electroinsulating polypyrrole layers covering the surface of metallic (Cu) monofilament. The developed multilayer monofilaments can be used as the initial material in wearable electronics. Influence of polymerisation conditions such as deposition time and the pressure of monomer vapours on morphological structure of plasma polypyrrole was analysed by using SEM technique. The results of research show, that plasma polymer layers deposited on the Cu cylindrical substrates are uniform, with thickness dependent on the time deposition and resistant to action of dynamic loads on a loom.