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The concept of sustainable use of materials defines as utilizing raw material as less aspossible and introducing less toxic substances to the environment as well. Smartmaterials are one route for sustainability, as they have optimal performance in relation tomaterial composition. New technologies can be developed by using smart materials. Onearea is the development of smart textiles, meaning the incorporation of electronicfunctions in textiles. These functions can be used for human protection or monitoring ofhealth.Conductivity is a key factor in smart textiles. The aim of this report is to identifyelectrically conductivity of textile fibres in conjunction with conductive polymer(polyaniline). By applying conductive polymer (polyaniline ink) on textiles fabric andfibres it is possible to obtain conductive textile products. This project focuses on thedevelopment of conductive fibres by coating of an individual fibre or a few differenttypes of fabric with conductive polymer polyaniline dispersion in water and toluene assolvent. Various situations have been taken into consideration and investigated fordifferent concentration to different times of coating and deposit thickness. Performanceon resistivity calculation led to find optimum concentration and coating numbers anddeposit thickness. Based on the inventory, a qualitative resistivity analysis is carried outfor the purpose of identifying which combination of concentration and times of coating inthe case of woven types fibre or coating thickness in the case of non woven types offabrics as well as the types of fabrics would provide the better conductivity properties in the textile fibres and fabrics.

Conducting polymer coating is the new developing area in the field of advanced textiles. In this project the rheological behaviour of paste containing conducting polymer was studied during formulation to coating application. The literature study is done by keeping all the contents of project in mind and a wide area of conductive polymer, coating methods, binder system and rheology modifier is covered. The rheological behaviour of different fluid containing newtanion and non-newtanion behaviour is discussed for better understanding of the project working. Polyester fabric was coated by knife coating method. In paste formulation, the chemicals used were polyurethane binder with two HEUR based rheology modifiers. A lot of experiments were performed to determine the right amount of rheology modifier alone or in combination for paste formulation and coating application and interesting findings were observed during the experimental work which had been justified in results and analysis. After application, the coated fabric was checked for resistivity. / Program: Magisterutbildning i textilteknologi

The currently accepted method for assessing the resistance of concrete to penetration of chloride ions is ASTM C1202, commonly known as the “Rapid Chloride Permeability (RCP) Test.” The test is time-consuming, laborious, has rather high variability, and, is to a degree, user sensitive, making it problematic for inclusion in a performance-based specification. A potential alternative to the RCP test is the “Surface Resistivity (SR) Test”, a method which is dramatically easier, faster, and has less variability than the RCP test. The research reported herein was directed toward determining a correlation between RCP and SR test measurements for Tennessee bridge deck concrete, based on cylinders collected from concrete bridge decks being constructed across the state, and evaluating the appropriateness of the SR test as an alternative to the RCP test for inclusion in a performance-based specification. Results of the testing showed a clear correlation between the two methods and identified potential limits for possible inclusion in a performance-based specification.

Please read the abstract in the dissertation Copyright / Dissertation (MSc)--University of Pretoria, 2013. / Chemical Engineering / unrestricted

Tato diplomová práce se zabývá přípravou nových kompozitů na bázi mikrofibrilované celulozy a multi-walls carbon nanotubes (MFC/MWCNTs). Tři různé metody byly použity pro modifikaci MWCNTs. Byl zkoumán vliv použitých modifikací na kvalitu MWCNTs suspense. Dále byly připraveny kompozity obsahující MFC a MWCNTs a vliv MWCNTs na mechanické a elektrické vlastnosti a morfologii byl zkoumán. MWCNTs suspense byly charakterizovány za použití UV-VIS spektrofotometrie, Rastrovacího elektronového mikroskopu (SEM) a Termogravimetrické analýzy (TGA). Elektrické vlastnosti byly měřeny pomocí Keithly Electrometer/High Resistivity Meter. Mechanické vlastnosti v tahu byly měřeny za použití Miniature Materials Tester a pro studium morfologie byl použit SEM. Žádný významný vliv MWCNTs na mechanické vlastnosti nebyl pozorován. Hodnoty získané z měření rezistivity vykazují typický perkolační trend a výrazného snížení rezistivity bylo dosaženo přidáním 1 – 2 wt.% MWCNTs. Nicméně hodnoty se velice liší pro horní a spodní stranu téhož vzorku. Ze získaných výsledků vyplývá, že klíčovým krokem ke zdokonalení vlastností materiálu jsou dobrá suspense MWCNTs a také dosažení vzájemné kompatibility obou složek.