Quando uma pessoa fricciona os sapatos num tapete, seu corpo pode carregar-se com um potencial de alguns milhares de volts em relação ao referencial de terra. Se esta pessoa tocar um objeto aterrado, uma faísca pode salta entre o objeto e a ponta do seu dedo. O corpo desta pessoa age como um capacitor, e um fluxo rápido de eletricidade estática armazenada, resultado das cargas estáticas armazenadas no copo, flui deste para um objeto de potencial menor. Essas descargas podem provocar desde pequenos danos, como desconforto físico, até incêndios em grandes construções. Na tentativa de minimizar ou eliminar esses problemas, tapetes e carpetes antiestáticos são utilizados. Muitos métodos têm sido propostos para caracterizar esses produtos de acordo com suas características eletrostáticas. Dentre eles, o recomendado pela norma francesa NF G35-025 [Essais des Revêtements de Sol Textiles-Propension à l\'accumulation de Charges Életrostatiques, Méthode d\'essai et spécification, Décembre 1983], prescreve que alguém usando sapatos especiais deve caminhar em uma amostra de tapete por longo período e, então, o potencial eletrostático adquirido por ele é medido através de um eletrômetro. Por este método são reproduzidas as condições reais, mas, ele é muito caro e trabalhoso, pois requer uma sala climatizada. Na tentativa de descobrir métodos alternativos, encontram-se na literatura vários estudos e métodos. Taylor [An Instrument for Measuring Static Dissipation from Materials, Journal of Electrostatics, (1987) 53-64, Elsevier Science Publishers B.V., Amsterdam-Printed in the Netherlands] desenvolveu um medidor de decaimento de carga para medir tempo de decaimento em polímeros antiestáticos. Nesse método, ele determinou uma boa correlação entre a resistência superficial e o tempo de meia-vida do material. Usando a mesma ideia, foi possível desenvolver o método apresentado nesta tese, aplicado a amostras de tapete e carpetes. Neste método, a caracterização eletrostática de tapetes ou carpetes é realizada também através da medida do tempo de decaimento do potencial eletrostático. Porém, sua ideia principal é que todas as medidas são realizadas dentro de uma câmara especial isenta de umidade, pois este pode influenciar o carregamento das amostras. Dentro desta câmara, as amostras de tapete ou carpete são inicialmente carregadas através de descarga corona, após cessar o carregamento, é medido o seu tempo de decaimento. Um programa computacional especialmente desenvolvido para este fim permite o controle da medição e do processo de carregamento. / When a person rubs his shoes in a rug, his body may be charged with a potential of some thousands of volts in relation to the earth reference. If this person touches a grounded object, a spark can travel between the object and the tip of his finger. The person\'s body acts like a capacitor, and a fast flow of stored static electricity, which is a result of the static loads stored in the body, flows from the body to an object in a smaller potential. Those discharges can cause from small damages, as physical discomfort, to fires in big constructions. ln the attempt to minimize or to eliminate these problems, antiestatic rugs and carpets are used. Many methods have been proposed 10 characterize those products in agreement with the electrostatic characteristics . Among them the recommended methods by the French standard NF G35-025 [Essais des Revêtements de Sol Textiles-Propension à I\'accumulation de Charges Életrostatiques, Méthode d\'essai et spécification, Décembre 1983], prescribe that somebody using special shoes should walk in a rug sample for a long period, and then the electrostatic potential acquired by him is measured using an electrometer. ln this method the real conditions are reproduced, but, it is very expensive and difficult, because it requires an aclimatized room. There are in the literature several studies attempting to devise alternative methods. Taylor [An Instrument goes Measuring Static Dissipation from Materiais, Journal of Electrostatics, (1987) 53-64, Elsevier Science Publishers B. V, Amsterdam-Printed in the Netherlands] developed a meter of charge decline to measure time of decline in antistatic polymers. ln his method, Taylor determined a good correlation between the superficial resistance and the time of stocking-life of the material. Using the same idea, it was possible to develop the method that is presented in this thesis, applied to samples of rugs and carpets. ln this method the electrostatic characterization of rugs or carpets is also accomplished through the measurement of the time of decline of the electrostatic potential. However its main idea is that all the measures are accomplished inside a special camera without humidity, since it can influence the charging of the samples. lnside this camera, the rugs or carpet samples are initially charged using corona discharge, after interrupting the charging, time of decline is measured. A computer program was especially developed for this reason, it allows the control of the measurement and of the charging process.

Quando uma pessoa fricciona os sapatos num tapete, seu corpo pode carregar-se com um potencial de alguns milhares de volts em relação ao referencial de terra. Se esta pessoa tocar um objeto aterrado, uma faísca pode salta entre o objeto e a ponta do seu dedo. O corpo desta pessoa age como um capacitor, e um fluxo rápido de eletricidade estática armazenada, resultado das cargas estáticas armazenadas no copo, flui deste para um objeto de potencial menor. Essas descargas podem provocar desde pequenos danos, como desconforto físico, até incêndios em grandes construções. Na tentativa de minimizar ou eliminar esses problemas, tapetes e carpetes antiestáticos são utilizados. Muitos métodos têm sido propostos para caracterizar esses produtos de acordo com suas características eletrostáticas. Dentre eles, o recomendado pela norma francesa NF G35-025 [Essais des Revêtements de Sol Textiles-Propension à l\'accumulation de Charges Életrostatiques, Méthode d\'essai et spécification, Décembre 1983], prescreve que alguém usando sapatos especiais deve caminhar em uma amostra de tapete por longo período e, então, o potencial eletrostático adquirido por ele é medido através de um eletrômetro. Por este método são reproduzidas as condições reais, mas, ele é muito caro e trabalhoso, pois requer uma sala climatizada. Na tentativa de descobrir métodos alternativos, encontram-se na literatura vários estudos e métodos. Taylor [An Instrument for Measuring Static Dissipation from Materials, Journal of Electrostatics, (1987) 53-64, Elsevier Science Publishers B.V., Amsterdam-Printed in the Netherlands] desenvolveu um medidor de decaimento de carga para medir tempo de decaimento em polímeros antiestáticos. Nesse método, ele determinou uma boa correlação entre a resistência superficial e o tempo de meia-vida do material. Usando a mesma ideia, foi possível desenvolver o método apresentado nesta tese, aplicado a amostras de tapete e carpetes. Neste método, a caracterização eletrostática de tapetes ou carpetes é realizada também através da medida do tempo de decaimento do potencial eletrostático. Porém, sua ideia principal é que todas as medidas são realizadas dentro de uma câmara especial isenta de umidade, pois este pode influenciar o carregamento das amostras. Dentro desta câmara, as amostras de tapete ou carpete são inicialmente carregadas através de descarga corona, após cessar o carregamento, é medido o seu tempo de decaimento. Um programa computacional especialmente desenvolvido para este fim permite o controle da medição e do processo de carregamento. / When a person rubs his shoes in a rug, his body may be charged with a potential of some thousands of volts in relation to the earth reference. If this person touches a grounded object, a spark can travel between the object and the tip of his finger. The person\'s body acts like a capacitor, and a fast flow of stored static electricity, which is a result of the static loads stored in the body, flows from the body to an object in a smaller potential. Those discharges can cause from small damages, as physical discomfort, to fires in big constructions. ln the attempt to minimize or to eliminate these problems, antiestatic rugs and carpets are used. Many methods have been proposed 10 characterize those products in agreement with the electrostatic characteristics . Among them the recommended methods by the French standard NF G35-025 [Essais des Revêtements de Sol Textiles-Propension à I\'accumulation de Charges Életrostatiques, Méthode d\'essai et spécification, Décembre 1983], prescribe that somebody using special shoes should walk in a rug sample for a long period, and then the electrostatic potential acquired by him is measured using an electrometer. ln this method the real conditions are reproduced, but, it is very expensive and difficult, because it requires an aclimatized room. There are in the literature several studies attempting to devise alternative methods. Taylor [An Instrument goes Measuring Static Dissipation from Materiais, Journal of Electrostatics, (1987) 53-64, Elsevier Science Publishers B. V, Amsterdam-Printed in the Netherlands] developed a meter of charge decline to measure time of decline in antistatic polymers. ln his method, Taylor determined a good correlation between the superficial resistance and the time of stocking-life of the material. Using the same idea, it was possible to develop the method that is presented in this thesis, applied to samples of rugs and carpets. ln this method the electrostatic characterization of rugs or carpets is also accomplished through the measurement of the time of decline of the electrostatic potential. However its main idea is that all the measures are accomplished inside a special camera without humidity, since it can influence the charging of the samples. lnside this camera, the rugs or carpet samples are initially charged using corona discharge, after interrupting the charging, time of decline is measured. A computer program was especially developed for this reason, it allows the control of the measurement and of the charging process.

The diploma thesis in the first part deals with a theoretical description of coating technologies, textile materials used in coatings, types of coated polymers and properties of coatings - especially adhesion. The experimental part of the work is devoted to the preparation of textile coatings from polyester fabric and coating based on addition silicone. Using the developed method of sample preparation for T-peel testing of the adhesive strength, the improvement of the adhesion of the coating by chemical adhesion with the support of adhesive agents was studied. The second method studied the change in compactness and adhesion of the coating to the fabric after shaking as a function of breathability. The influence of side reactions of reagents on silicone cohesion was studied by preparing dogbones for testing tensile-deformation properties. The research also included the characterization of silicone samples using ATR-FTIR, monitoring the weight gain and thickness of the fabric after coating, the feel and color stability of the applied fabric and observing the coating under an optical microscope.

The focus of the project was to alter and optimize the water repellant textile coating formulations to reach enhanced durability. For this purpose, the project was approached with three methods. Firstly, bio-based components were implemented in the mother emulsion to act as surfactant and crosslinking agent and to provide hydrophobic properties. Secondly different binders were added to crosslink and increase the coating resistance towards washes. Lastly additives at nano-scale were added to increase surface roughness in order to obtain higher hydrophobicity and improved of crosslinking capacity due to the presence of more functional groups.  The stability of all emulsions was controlled using different techniques such as optical microscopy to determine particle size, distribution and any observable instability (flocculation etc.), normal aging at room temperature and accelerated aging using higher temperature. All coatings were applied using a laboratory padder on standard PA and PES pieces of textiles and hydrophobic performance was evaluated through ISO 4920 spray test. By standard washing and repeating spray test, durability could be assessed. Further structure and property studies have been run using other tests such as: contact angle measurement, breathability of the coating and SEM observations. Based on the obtained results the incorporation of low HLB, bio-based surfactants in low amount (~0,25%) resulted in an increase in the hydrophobic performance of the tested textiles. However, a decrease in shelf life could be observed with these surfactants at room temperature. Sonication was successfully used to increase both stability and shelf life significantly. Some binders and nanoparticles proved to be successful in increasing the coating quality and thus the durability. Overall many of the developed formulations could enhance performance on PA compared to the already present commercial product. On PES textile, however, the developed strategies yielded hydrophobic effect close to the commercial product.

Mechanical performance characteristics were compared for 100% polyester treated and untreated weft-knitted mesh fabric that are used to contain dry-ageing hams, commonly referred to as ham nets. The treated net was coated with a patent-pending food-grade chemical solution (40% Propylene Glycol + 1% Propylene Glycol Alginate + 1% Carrageenan) to control ham mites. Both treated and untreated ham nets were compared for mechanical performance characteristics based on the following standards: abrasion resistance (ASTM D4966), elastic recovery (BS EN 14704-1:2005), breaking strength (ASTM D5034-09), and bursting strength (ASTM D3786). Results indicate that the coating had minimal to no impact on the mechanical performance characteristics of ham nets. SEM images also showed no negative effect on the fiber morphology due to the applied chemical solution. Findings support the use of treated ham nets to increase the end-use functionality and provide stakeholders an option for integrated pest management without compromising performance needs.

In smart textiles, electrical conductivity is often required for several functions, especially contacting (electroding) and interconnecting. This thesis explores electrically conductive textile surfaces made by combining conventional textile coating methods with the intrinsically conductive polymer complex poly(3,4-ethylene dioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS). PEDOT:PSS was used in textile coating formulations including polymer binder, ethylene glycol (EG) and rheology modifier. Shear viscometry was used to identify suitable viscosities of the formulations for each coating method. The coating methods were knife coating, pad coating and screen printing. The first part of the work studied the influence of composition of the coating formulation, the amount of coating and the film formation process on the surface resistivity and the surface appearance of knife-coated textiles. The electrical resistivity was largely affected by the amount of PEDOT:PSS in the coating and indicated percolation behaviour within the system. Addition of a high-boiling solvent, i.e. EG, decreased the surface resistivity with more than four orders of magnitude. Studies of tear strength and bending rigidity showed that textiles coated with formulations containing larger amounts of PEDOT:PSS and EG were softer, more ductile and stronger than those coated with formulations containing more binder. The coated textiles were found to be durable to abrasion and cyclic strain, as well as quite resilient to the harsh treatment of shear flexing. Washing increased the surface resistivity, but the samples remained conductive after five wash cycles. The second part of the work focused on using the coatings to transfer the voltage signal from piezoelectric textile fibres; the coatings were first applied using pad coating as the outer electrode on a woven sensor and then as screen-printed interconnections in a sensing glove based on stretchy, warp-knitted fabric. Sensor data from the glove was successfully used as input to a microcontroller running a robot gripper. These applications showed the viability of the concept and that the coatings could be made very flexible and integrated into the textile garment without substantial loss of the textile characteristics. The industrial feasibility of the approach was also verified through the variations of coating methods.

V diplomové práci je prezentovaná literární rešerše na téma termochromní pigmenty a jejich aplikace v polymerních matricích. Výzkum byl zaměřen na hlubší pochopení termochromního efektu v pigmentech na bázi molekulárních komplexů. Termochromní pigmenty byly aplikovány do polyuretanového textilního zátěru a bylo zjištěno optimální nastavení podmínek zátěru. Textilní zátěry byly podrobeny termickým zkouškám a zároveň byla pozorována jejich stálobarevnost.