This thesis, written by Ingrid Öberg Månsson at KTH Royal Institute of Technology and entitled “Electroanalytical devices with fluidic control using textile materials and methods”, presents experimental studies on the development of textile based electronic devices and biosensors. One of the reasons why this is of interest is the growing demand for integrated smart products for wearable health monitoring or energy harvesting. To enable such products, new interdisciplinary fields arise combining traditional textile technology and electronics. Textile based devices have garnered much interest in recent years due to their innate ability to incorporate function directly into, for example, clothing or bandages by textile processes such as weaving, knitting or stitching. However, many modifications of yarns required for such applications are not available on an industrial scale. The major objective of this work has been to study how to achieve the performance necessary to create electronic textile devices by either coating yarns with conductive material or using commercially available conductive yarns that are functionalized to create sensing elements. Further, liquid transport within textile materials has been studied to be able to control the contact area between electrolyte and electrodes in electrochemical devices such as sensors and transistors. Yarns with specially designed cross-sections, traditionally used in sportswear to wick sweat away from the body and enhance evaporation, was used to transport electrolyte liquids to come in contact with yarn electrodes. The defined area of the junction where the fluidic yarn meets the conductive yarn was shown to increase stability of the measurements and the reproducibility between devices. The results presented in the two publications of this thesis as well as additional results presented in the thesis itself show the promising potential of using textile materials to integrate electronic and electrochemical functionality in our everyday life. This is shown by using basic textile materials and processing techniques to fabricate complex devices for various application areas such as sensors and diagnostics as well as electrical and energy harvesting components. / Denna avhandling, skriven av Ingrid Öberg Månsson vid Kungliga Tekniska Högskolan och titulerad ”Elektroanalytiska sensorer med vätskekontroll integrerad genom användande av textila material och metoder”, presenterar experimentella studier inom utvecklingen av textilbaserade elektroniska komponenter och biosensorer. Detta är av intresse på grund av den ökade efterfrågan på integrerade smarta produkter som till exempel bärbara sensorer för hälsoövervakning eller för att samla upp och konvertera energi till elektricitet. För att möjliggöra denna typ av produkter föds nya interdisciplinära fält där traditionell textilteknologi och elektronik möts. Textilbaserade enheter har väckt stort intresse under de senaste åren på grund av den naturliga förmågan att integrera funktion i till exempel kläder eller förband genom textila tillverkningsprocesser som väveri, stickning eller sömnad. Många modifikationer hos garner som krävs för att möjliggöra sådana tillämpningar är dock inte tillgängliga i större skala. Därför har det huvudsakliga syftet med denna studie varit att undersöka hur man kan uppnå den prestanda som krävs för att tillverka elektroniska textila komponenter, antingen genom att belägga garner med elektroniskt ledande material eller genom att använda kommersiellt tillgängliga ledande garner som sedan modifieras kemiskt för att skapa sensorer. Utöver detta har vätsketransport inom textila material studerats för att kunna styra och kontrollera kontaktytan mellan elektrolyt och elektroder i elektrokemiska enheter så som sensorer och transistorer. Garner med speciella tvärsnitt, som traditionellt använts i sportkläder för att transportera svett bort från kroppen och underlätta avdunstning, har använts för att transportera elektrolytvätska till elektroder av garn. Den definierade kontaktytan där det vätsketransporterade garnet korsar elektrodgarnet har visats öka stabiliteten av mätningen och reproducerbarheten mellan mätenheter. Resultaten som presenteras i de två artiklar som denna avhandling bygger på samt i avhandlingen själv visar på lovande potential för användandet av textila material för att integrera elektronisk och elektrokemisk funktionalitet i våra vardagsliv. Detta har uppnåtts genom att använda grundläggande textila material och tillverkningsprocesser för att tillverka komplexa enheter för olika tillämpningsområden så som sensorer för diagnostik samt elektroniska komponenter. / <p>QC 2020-08-21</p>

Nanopartiklar (NP) erbjuder unika möjligheter för medicinska tillämpningar, inklusive kontrollerad frisättning av cancerläkemedel, användning som bildkontrast vid avbildningsprocedurer eller hypertermisk behandling av cancerceller. Flash nanoprecipitation (FNP) producerar NPs för att kombinera dessa tillämpningar i en snabb, billig och skalbar beläggningsprocess. Användning av FNP med en Multi-Inlet Vortex Mixer (MIVM) är en lovande metod för att enkelt belägga hydrofoba oljesyra järnoxid NP (IONP) med olika biokompatibla block-copolymerer. Amfifila block-copolymerer baserade på hydrofil polyetylenglykol (PEG) och hydrofob poly(laktid) (PLA), poly(laktid-co-glykolid) (PLGA) eller poly(kaprolakton) (PCL) syntetiserades framgångsrikt. Den organiska katalysatorn 1,8-diazabicyclo[5.4.0]undec-7-en (DBU) användes för att öka biokompatibiliteten hos de resulterande polymererna PEG-PLA, PEG-PL7,5KG2,5KA och PEG2K-PCL2K. Syntes av hydroxylterminerad poly(akrylsyra) (PAA-OH) följt av polymerisation med PLGA prövades. De amfifila blockpolymererna användes i kombination med stabilisatorn polysorbat 80 (Tween80®) i FNP för att bilda nakna polymera NP med en MIVM som reaktor. DLS och STEM bekräftade partikelstorlekar mellan 50 - 100 nm. Tillsatsen av 13 ± 2 nm hydrofoba oljesyra-IONPs gav en ökning av partikelstorleken samt en ökning av partikelstabiliteten över tid. STEM-bilder visade att enstaka IONPs fästs på utsidan av de polymera NPs. Hydrofoba interaktioner mellan polymeren och oleinsyra-IONPs är möjliga. För att uppnå inkapsling av oljesyra-IONPs bör justeringar av processparametrarna för FNP övervägas i framtida forskning. Ytterligare experiment krävs för att utforska möjliga läkemedelstillsatser, frisättningsmekanismer och hypertermi hos de polymerbelagda IONP-partiklarna. / Nanoparticles (NPs) offer unique possibilities for medical applications, including the controlled release of cancer drugs, the use as imaging contrast during imaging procedures or the hyperthermic treatment of cancer cells. Flash nanoprecipitation (FNP) produces NPs to combine these applications in a fast, cheap, and scalable coating process. The use of FNP with a Multi-Inlet Vortex Mixer (MIVM) is a promising method to easily coat hydrophobic oleic acid iron oxide NPs (IONPs) with various biocompatible block-copolymers. Amphiphilic block-copolymers based on hydrophilic polyethylene glycol (PEG) and hydrophobic poly(lactic acid) (PLA), poly(lactic-co-glycolic acid) (PLGA) or poly(caprolactone) (PCL) were successfully synthesized. The organic catalyst 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) was used to increase biocompatibility of the resulting polymers PEG-PLA, PEG-PL7.5KG2.5KA and PEG2K-PCL2K. The synthesis of hydroxyl terminated poly(acrylic acid) (PAA-OH) followed by the polymerization with PLGA was attempted. The amphiphilic block-copolymers were used in combination with the stabilizer polysorbate 80 (Tween80®) in FNP to form bare polymeric NPs using a MIVM as the reactor. DLS and STEM confirmed particle sizes between 50 - 100 nm. The addition of 13 ± 2 nm hydrophobic oleic acid IONPs yielded an increase in particle size as well as increase in particle stability over time. STEM images showed attachment of single IONPs to the outside of the polymeric NPs. Hydrophobic interactions between the polymer and oleic acid IONPs are possible. To achieve encapsulation of the oleic acid IONPs, adjustments to the process parameters of FNP should be considered in future research. Additional experiments are required to explore possible drug addition, release mechanisms and hyperthermia behavior of the polymer coated IONPs particles.

För att möjliggöra en hållbar utveckling skiftar många polymerforskares fokus just nu från att syntetisera polymerer från fossila resurser till att producera biobaserade polymerer från exempelvis träd. Av särskilt intresse är lignin, som utgör ungefär en tredjedel av allt växtmaterial men i nuläget oftast används som bränsle. Många forskare har undersökt de möjligheter som öppnas genom att bryta ner lignin och modifiera molekylerna som fås därigenom, såsom ferulsyra. Denna studie syftade till att modifiera ferulsyra till en styren-lik monomer med en karboxyl-substituent, och att testa vattenbaserad polymerisation av denna monomer.Det första steget i modifiering var dekarboxylering av ferulsyra. Detta utfördes genom upprepningar av tidigare studier där baskatalyserad dekarboxylering utfördes i polära aprotiska lösningsmedel. Efter flera försök hittades en fungerande metod, där trietylamin gav en dekarboxylering med högt utbyte efter tre timmar i dimetylformamid vid 100 °C. Att isolera produkten var också utmanande i början, men en trestegs-extraktion med H2O och Et2O som avslutades med en tvätt av saltvatten gav tillräcklig renhet. En ättiksyra-grupp adderades till fenolen med hjälp av en tvåstegsreaktion som hittades i litteraturen, men inte förrän ett dussin försök till nya metoder med kloroättiksyra gjorts utan framgång. I den fungerande metoden tillsattes en acetatgrupp med metylbromoacetat i återkokande aceton med kaliumkarbonat som bas, innan acetatet demetylerades av litiumhydroxid i en metanol/vattenblandning vid rumstemperatur.Den resulterande monomeren, 4-oxy-ättiksyra-3-methoxy-styren (OAMS), sampolymeriserades med styren, både i bulk- och emulsionspolymerisation. Bulksampolymeren hade en något högre molekylvikt och glastransitionstemperatur än homopolystyren, med en betydligt högre dispersitet. Emulsionspolymerisation var utmanande, eftersom OAMS inte är särskilt löslig i vare sig vatten eller styren, och i slutändan producerades inga tydliga resultat genom dessa försök.  Studiens huvudsakliga slutsats är att även om det är möjligt att syntetisera ren OAMS från ferulsyra, är användbarheten av denna molekyl som monomer i vattenbaserad polymerisering inte övertygande, eftersom den är så pass olöslig om inte bas tillsätts, vilket introducerar risken för hydrolys.Slutligen, även om studien ledde till få säkra slutsatser på grund av flera ofullständiga resultat, uppnåddes huvudsyftet att modifiera ferulsyra och testa polymerisation av den bildade monomeren. / To enable a sustainable development, scientific focus is shifting from synthesizing polymers from fossil-based resources to producing bio-based polymers from for example wood. Of particular interest is lignin, which makes up about a third of plant matter but is nowadays most commonly used as fuel. A great deal of research has explored the possibilities opened up by breaking down lignin and modifying its derived molecules, such as ferulic acid. This study aimed to modify ferulic acid into a styrenic monomer with an acidic substituent, and to investigate the aqueous polymerization of this monomer.The first step of modification was the decarboxylation of ferulic acid. This was attempted through recreations of previous studies where base-catalysed decarboxylation was carried out in aprotic polar solvents. After several trials, a successful procedure was found, where triethylamine gave a high-yield decarboxylation after three hours in dimethylformamide at 100 °C. Isolating the product was also initially challenging, but a three-step extraction with H2O and Et2O finished by a wash of brine gave sufficient purity.Adding an acetic acid-group to the phenol was achieved using a two-step procedure found in literature, but not before trying a dozen novel methods using chloroacetic acid without success. In the working procedure, an acetate group was added using methyl bromoacetate in refluxed acetone with potassium carbonate as base, before demethylating the acetate using lithium hydroxide in a methanol/water mix at room temperature. The resulting monomer, 4-oxy-acetic acid-3-methoxy-styrene (OAMS), was copolymerized with styrene, both in bulk and emulsion radical polymerization. The bulk copolymer displayed a slightly higher molecular weight and glass transition temperature than homopolystyrene, with a significantly higher dispersity. Emulsion polymerization was challenging, as OAMS is not very soluble in either water or styrene, and ultimately, no conclusive results were produced through this route.The study concluded that while it is possible to synthesize pure OAMS from ferulic acid, the degree of usability of this molecule as a monomer in aqueous polymerization is not certain, as it is hardly soluble without the addition of base, which introduces the risk of hydrolysis. Ultimately, although few solid conclusions could be drawn from this study due to several incomplete results, the core objective of modifying ferulic acid and testing polymerization of the resulting monomer was achieved.

Nanocomposites of polyethylene and metal oxide nanoparticles have shown to be a feasible approachto the next generation of insulation in high voltage direct current cables. In order to reach an operationvoltage of 1 MV new insulation materials with reduced conductivity and increased breakdown strengthas compared to modern low-density polyethylene (LDPE) is needed.In this work polyethylene MgO nanocomposites for electrical insulation has been produced andcharacterized both from an electrical and material perspective. The MgO nanoparticles weresynthesized into polycrystalline nanoparticles with a large specific surface area (167 m2 g–1). Meltprocessing by extrusion resulted in evenly dispersed MgO nanoparticles in LDPE for the silane surfacemodified MgO as compared to the unmodified MgO. All systems showed a reduction in conductivityby up to two orders of magnitude at low loading levels (1–3 wt.%), but where the surface modifiedsystems were able to retain reduced conductivity even at loading levels of 9 wt.%. A maximuminteraction radius to influence the conductivity of the MgO nanoparticles was theoretically determinedto ca. 800 nm. The interaction radius was in turn experimentally observed around Al2O3 nanoparticlesembedded in LDPE using Intermodulation electrostatic force microscopy. By applying a voltage on theAFM-tip charge injection and extraction around the Al2O3 nanoparticles was observed, visualizing theexistence of additional localized energy states on, and around, the nanoparticles. Ptychography wasused to reveal nanometre features in 3D of electrical trees formed under DC-conditions. Thevisualization showed that the electrical tree grows by pre-step voids in front of the propagatingchannels, facilitating further growth, much in analogy to mechanical crack propagation (Griffithconcept). An electromechanical effect was attributed as possible mechanism for the formation of the voids. / Nanokompositer av polyeten och metalloxidpartiklar anses vara möjliga material att använda i morgondagens isolationshölje till högspänningskablar för likström. För att nå en transmissionsspänning på 1 MV behövs isolationsmaterial som i jämförelse med dagens polyeten har lägre elektrisk ledningsförmåga, högre styrka mot elektriskt genomslag och som kan kontrollera ansamling av rymdladdningar. De senaste årens forskning har visat att kompositer av polyeten med nanopartiklar av metalloxider har potential att nå dessa egenskaper. I det här arbetet har kompositer av polyeten och nanopartiklar av MgO för elektrisk isolation producerats och karaktäriserats. Nanopartiklar av MgO har framställts från en vattenbaserad utfällning med efterföljande calcinering, vilket resulterade i polykristallina partiklar med en mycket stor specifik ytarea (167m2 g-1). MgO-nanopartiklarna ytmodifierades i n-heptan genom att kovalent binda oktyl(trietoxi)silan och oktadekyl(trimetoxi)silan till partiklarna för att skapa en hydrofob och skyddande yta. Extrudering av de ytmodifierade MgO nanopartiklarna tillsammans med polyeten resulterade i en utmärkt dispergering med jämnt fördelad partiklar i hela kompositen, vilket ska jämföras med de omodifierade partiklarna som till stor utsträckning bildade agglomerat i polymeren. Alla kompositer med låg fyllnadsgrad (1–3 vikt% MgO) visade upp till 100 gånger lägre elektrisk konduktivitet jämfört med värdet för ofylld polyeten. Vid högre koncentrationer av omodifierade MgO förbättrades inte de isolerande egenskaperna på grund av för stor andel agglomerat, medan kompositerna med de ytmodifierade fyllmedlen som var väl dispergerade behöll en kraftig reducerad elektrisk konduktivitet upp till 9 vikt% fyllnadshalt. Den minsta interaktionsradien för MgO-nanopartiklarna för att minska den elektriska konduktiviten i kompositerna fastställdes med bildanalys och simuleringar till ca 800 nm. Den teoretiskt beräknade interaktionsradien kompletterades med observation av en experimentell interaktionsradie genom att mäta laddningsfördelningen över en Al2O3-nanopartikle i en polyetenfilm med intermodulation (frekvens-mixning) elektrostatisk kraftmikroskop (ImEFM), vilket är en ny AFM-metod för att mäta ytpotentialer. Genom att lägga på en spänning på AFM-kantilevern kunde det visualiseras hur laddningar, både injicerades och extraherades, från nanopartiklarna men inte från polyeten. Det tolkades som att extra energinivåer skapades på och runt nanopartiklarna som fungerar för att fånga in laddningar, ekvivalent med den gängse tolkningen att nanopartiklar introducera extra elektronfällor i den polymera matrisen i nanokompositer. Nanotomografi användes för att avbilda elektriska träd i tre dimensioner. Avbildningen av det elektriska trädet visade att tillväxten av trädet hade skett genom bildning av håligheter framför den framväxande trädstrukturen. Håligheterna leder till försvagning av materialet framför det propagerande trädet och förenklar på det sättet fortsatt tillväxt. Bildningen av håligheter framför trädstrukturen uppvisar en analogi till propagering av sprickor vid mekanisk belastning, i enlighet med Griffiths koncept. / <p>QC 20161006</p>

Electrochemical systems, which rely on coupled phenomena of the chemical change and electricity, have been utilized for development an interface between biological systems and conventional electronics.  The development and detailed understanding of the operation mechanism of such interfaces have a great importance to many fields within life science and conventional electronics. Conducting polymer materials are extensively used as a building block in various applications due to their ability to transduce chemical signal to electrical one and vice versa. The mechanism of the coupling between the mass and charge transfer in electrochemical systems, and particularly in conductive polymer based system, is highly complex and depends on various physical and chemical properties of the materials composing the system of interest. The aims of this thesis have been to study electrochemical systems including conductive polymer based systems and provide knowledge for future development of the devices, which can operate with both chemical and electrical signals. Within the thesis, we studied the operation mechanism of ion bipolar junction transistor (IBJT), which have been previously utilized to modulate delivery of charged molecules. We analysed the different operation modes of IBJT and transition between them on the basis of detailed concentration and potential profiles provided by the model. We also performed investigation of capacitive charging in conductive PEDOT:PSS polymer electrode. We demonstrated that capacitive charging of PEDOT:PSS electrode at the cyclic voltammetry, can be understood within a modified Nernst-Planck-Poisson formalism for two phase system in terms of the coupled ion-electron diffusion and migration without invoking the assumption of any redox reactions. Further, we studied electronic structure and optical properties of a self-doped p-type conducting polymer, which can polymerize itself along the stem of the plants. We performed ab initio calculations for this system in undoped, polaron and bipolaron electronic states. Comparison with experimental data confirmed the formation of undoped or bipolaron states in polymer film depending on applied biases. Finally, we performed simulation of the reduction-oxidation reaction at microband array electrodes. We showed that faradaic current density at microband array electrodes increases due to non-linear mass transport on the microscale compared to the corresponding macroscale systems.  The studied microband array electrode was used for developing a laccase-based microband biosensor. The biosensor revealed improved analytical performance, and was utilized for in situ phenol detection.

Food packaging should ensure the safety and quality of food, minimize spoilage and provide an easy way of storing and handling it. Barrier coatings are generally used to meet the demands placed on fibre-based food packages, as these have the ability to regulate the amount of gases that can enter them. Some gases are detrimental to food quality: oxygen, for example, initiates lipid oxidation in fatty foods. Using both experimental data and computer modelling, this thesis explains some aspects of how the structure of barrier coatings influences the mass transport of oxygen with the aim of obtaining essential knowledge that can be used to optimize the performance of barriers. Barrier coatings are produced from polyvinyl alcohol and kaolin blends that are coated onto a polymeric support. The chemical and physical structures of these barriers were characterized according to their influence on permeability in various climates. At a low concentration of kaolin, the crystallinity of polyvinyl alcohol decreased; in the thinner films, the kaolin particles were orientated in the basal plane of the barrier coating. The experimental results indicated a complex interplay between the polymer and the filler with respect to permeability. A computer model for permeability incorporating theories for the filled polymeric layer to include the polymer crystallinity, addition of filler, filler aspect ratio and surrounding moisture was developed. The model shows that mass transport was affected by the aspect ratio of the clay in combination with the clay concentration, as well as the polymer crystallinity. The combined model agreed with the experiments, showing that it is possible to combine different theories into one model that can be used to predict the mass transport. Four barrier coatings: polyethylene, ethylene vinyl alcohol + kaolin, latex + kaolin and starch were evaluated using the parameters of greenhouse gas emissions and product costs. After the production of the barrier material, the coating process and the end-of-life handling scenarios were analysed, it emerged that starch had the lowest environmental impact and latex + kaolin had the highest. / Food packaging is required to secure the safety and quality of food, as well as minimize spoilage and simplify handling. Barrier coatings are generally used to meet the demands placed on fibre-based food packages, as these have the ability to regulate the amount of gases that can enter them. Some gases are detrimental to food quality: oxygen, for example, initiates lipid oxidation in fatty foods. This thesis focuses on the mass transport of oxygen in order to gain deeper knowledge of, and thereby optimise, the performance of barrier coatings. This experimental study, together with computer modelling, characterized the structure of barrier materials with respect to the mass transport process. The performance of the barriers was evaluated based on the parameters of environmental impact and product costs. As the long-term aim is to use non-petroleum-based barrier coatings for packaging, these should be evaluated by assessing the properties of the material in question, its functionality and its environmental impact to provide more insight into which materials are desirable as well as to develop technology. The results from this study indicate that several parameters (the orientation, concentration and aspect ratio of the clay and the polymer crystallinity) influence the properties of a barrier. Using this knowledge, researchers and food packaging engineers can work toward improving and customising renewable barriers. / VIPP

Formsprutning är en tillverkningsmetod somställer krav på produkters utformning. För att göra en lämplig ingötsplacering räcker inte alltid riktlinjer utan en produktspecifik analys kan vara nödvändig. Materialval kräver en tydlig kravspecifikation och kan med fördel göras i samråd med en materialexpert. Riktlinjer för Design for manufacturing and assembly inkluderar bland annat rekommendationer för formgivning. Detta kandidatarbete strävar efter att hjälpa produktutvecklare att tidigt i produktutvecklingsprocessen ta hänsyn till tillverkningsaspekter. Baserat på litteraturstudier, intervjuer och fallstudier har riktlinjer tagits fram för materialval, design for manufacturing and assembly och formgivning för formsprutning. Arbetet är avgränsat till att endast titta på formsprutningsbara termoplaster. Arbetet, som genomförts vid Linköpings universitet, är en del av projektet Säkra monteringsverktyg som resulterade i ett portabelt dödmansgrepp. Defallstudier som genomfördes inom projektetbehandlar värdering av koncept utifrån produktionsperspektiv, materialval och formsprutningsanalyser i programmet Moldflow. Arbetet resulterade i riktlinjer för applicering av metoden design for manufacturing and assembly, formsprutningsanpassning samt materialval. Fallstudien i Säkra monteringsverktyg utmynnade ien värdering av koncept utifrån produktionsaspekter, ett materialval baserat på projektets kravspecifikation och rekommendationer för produktens utformning med syfte att optimera dess tillverkning. En slutsats av arbetet är att produktionsanpassning av produktens utformning bör ske tidigt i utvecklingsprocessen. En annan slutsats är att besök i industrin, hos exempelvis ett formsprutningsföretag, leder till bättre förståelse av vilka krav som behöver uppfyllas för att en produkt ska vara möjlig att producera. Om simuleringsprogram för formsprutning finns bör det användas i kombination med riktlinjer för produktutformning. Ytterligare en slutsats som gjorts är att materialval underlättas genom tidig kontakt med materialleverantörer. Materialvalet baseras på kravspecifikationen och därför bör kraven tydliggöras och dess rimlighet kontrolleras innan materialvalet sker. / Injection molding is a manufacturing method that requires specific features to attain manufacturability. Gating suitability requires analysis and mere guidelines do not always provide the correct gate placement. Material selection requires a pronounced specification and is preferably supervised by an expert. Guidelines concerning design for manufacturing and assembly include, among other things, recommendations directly affecting the shape of the product. The aim for this bachelor thesis is to aid product developers and designers in taking manufacturing aspects into account early in the product development process. This is achieved by providing them with guidelines regarding material selection, injection molding, as well as design for manufacturing and assembly. The thesis is limited to thermoplastic materials suitable for injection molding and its results are based off thorough literature research, interviews and case studies. This bachelor thesis project, which is conducted at Linköping University,is a part of a project calledSafe manual assembly tools, and the resulting portable enabling device developed in Safe manual assembly toolsis used as case studies in this thesis. The case studies include: evaluation of concepts concerning manufacturability; material selection; and injection molding analysis through the software Moldflow. The thesis results in guidelines concerning design for manufacturing and assembly, injection molding and material selection. The case study is requited with concept selection suggestions, a selection of material that meets the specification of requirements stated in Safe manual assembly tools and design recommendations that aim to improve the manufacturability of the concept. This bachelor thesis concludes that design alterations striving to meet requirements for manufacturability should be made early in the devolpment process. Visiting the polymer-based product manufacturing industry offers better insight into which requirements that need to be fulfilled to make a product producible. Injection molding simulation software, if such is available, should be used in combination with design guidelines.The thesis also concludes that material selection is simplified through early contact with suppliers of material. Material selection is based off the specification of requirements and therefore requirements specified in the specification should be clarified and have their plausibility confirmed before the selection takes place.

Every artifact in this consumerism world is connected to Earth’s four ecological layers. Everything around us, air, organism, water, and soil/rock also known by the names; atmosphere, biosphere, hydrosphere, and lithosphere. All together form the ecosphere, the place that contains all materials and resources that we use when creating artifacts.  »Every material that we use comes from the ecosphere and eventually goes back to it.« - Ann Thorpe The way humans use, extract, manufacture and dispose of materials has concerned me for many years, long before I started this design program. It has formed my way of making as a designer, and because of my love for textiles, I have been applying it in that field of practise. I want to design textiles that function and can be used frequently, with a purpose and in the end, decompose before I do. The aim of this conducted design project is to, in a playful way, break down the barrier between maker and user. Combined with unfolding the hidden truths about garments, how they are manufactured and where those textile components originate from. This would enable me to broaden my knowledge in the field and in return I will have the opportunity to share my insights with the public. Within this project I will also put the emphasis on the impact textiles have on our bodies, reproductive health and surrounding ecosystems.  Designing with the intention to highlight topics like this, the whole life cycle of garments, creates a stronger bond between user and maker. This is something I as a designer and maker want to build my foundation on.  In order to do this I needed to pin down where this conducted design project could take place and what sustainable possibilities of change it could embed for the future.

El presente trabajo tiene por objetivo estudiar las aplicaciones de los nanocristales o ¿nanowhiskers¿ extraídos mediante hidrólisis ácida de celulosa bacteriana (BCNW) para el desarrollo de materiales poliméricos y biopoliméricos con propiedades mejoradas para su uso en aplicaciones de envasado de alimentos. En primer lugar se estudió y optimizó el proceso de extracción de BCNW. Se desarrolló un procedimiento de extracción con ácido sulfúrico, que permitió obtener nanocristales con elevada relación de aspecto y cristalinidad y al mismo tiempo, un elevado rendimiento de extracción. Este procedimiento comprende una posterior etapa de neutralización que resultó ser necesaria para garantizar la estabilidad térmica de los nanocristales. El siguiente paso consistió en la formulación de materiales nanocompuestos con propiedades mejoradas incorporando BCNW en diferentes matrices plásticas, en concreto copolímeros de etileno-alcohol vinílico (EVOH), ácido poliláctico (PLA) y polihidroxialcanoatos (PHAs). Mediante las técnicas de electroestirado y estirado por soplado se generaron fibras híbridas de EVOH y PLA con BCNW. La incorporación de BCNW en las disoluciones empleadas para producir fibras modificó significativamente sus propiedades (viscosidad, tensión superficial y conductividad) y por tanto, la morfología de las fibras se vio afectada. Además, se generaron fibras con propiedades antimicrobianas mediante la incorporación de aditivos, maximizando el efecto antimicrobiano con la adición de sustancias de carácter hidrofílico. Seguidamente, se produjeron nanocompuestos por mezclado en fundido y se desarrollaron técnicas de pre-incorporación de BCNW para evitar la aglomeración de los mismos no sólo en matrices hidrofílicas como el EVOH, sino también en matrices hidrofóbicas como el PLA. La dispersión óptima de BCNW resultó en una mejora de las propiedades mecánicas y de barrera de los nanocompuestos. También se estudió la modificación de la superficie de los nanocristales mediante copolimerización con poli(glicidil metacrilato) para mejorar la compatibilidad de BCNW con una matriz hidrofóbica como el PLA. Se incluyen además los primeros resultados obtenidos en cuanto a la producción de nanobiocompuestos sintetizados por microorganismos, que consisten en PHAs con diferentes contenidos de hidroxivalerato reforzados con BCNW. Por último, se desarrollaron películas con propiedades de alta barrera basadas en películas de BCNW recubiertas con capas hidrofóbicas. El recubrimiento mediante la deposición de fibras por electrospinning seguido de homogeneización por calentamiento garantizó una buena adhesión entre las diferentes capas, protegiendo así las películas de BCNW del efecto negativo de la humedad. / Martínez Sanz, M. (2013). Bacterial cellulose nanowhiskers to enhance the properties of plastics and bioplastics of interest in food packaging [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/30312 / TESIS / Premios Extraordinarios de tesis doctorales

[pt] Ao longo das últimas décadas, mais intensamente, a microscopia de força atômica (AFM) tem sido utilizada em atividades de pesquisa e desenvolvimento, notadamente para a caracterização de materiais. Não obstante os avanços e sofisticações da técnica, a determinação do módulo de elasticidade de materiais poliméricos continua sendo um desafio dada a complexidade de caracterização de materiais complexos, comumente gerando expressivo espalhamento nos resultados de medição. Esta pesquisa de mestrado apresenta mapeamentos da morfologia e medições do módulo de elasticidade de celulose comercial (fibras de bambu e de eucalipto) e lignocelulósico, referenciados a materiais poliméricos sintéticos já caracterizados (considerados como padrão). A microscopia de força atômica (AFM), no modo peak force tapping, alternativamente fundamentada no modelo Derajaguin-Muller-Toporo, DMT (que é o modelo incorporado no software da Bruker, fabricante do equipamento AFM) e no modelo JohnsonKendall-Robert, JKR (proposto neste trabalho, fazendo-se uso de um algoritmo Matlab), foi utilizada como técnica de medição do módulo de elasticidade dos materiais investigados. A partir dos ensaios realizados, foi possível avaliar o método de medição com base em critérios metrológicos e determinar o modelo de cálculo mais apropriado para a caracterização dos materiais investigados. Para os materiais padrão utilizados como referência, e cujos valores do módulo de elasticidade são informados pelos respectivos fornecedores (E igual 2,7 mais ou menos 0,1 GPa, para o poliestireno e E igual 1,8 GPa, para a poliamida), o modelo JKR mostrou-se mais adequado para fundamentar o cálculo do módulo de elasticidade. Enquanto o modelo JKR reproduziu o valor do fabricante com 6,3 porcento, para o caso do poliestireno (E igual 2,540754 mais ou menos 0,056 GPa) e com 12,5 porcento, para o caso da poliamida (E igual 1,680050 mais ou menos 0,041 GPa), o modelo DMT produziu resultados com desvios superiores a 50 porcento do valor de referência considerado como padrão. Fundamentado nesses mesmos modelos DMT e JKR, o trabalho avaliou o módulo de elasticidade de outros materiais, mais especificamente: (i) filme de celulose extraída do eucalipto; (ii) filme de celulose microfobrilada comercial; (iii) filme de celulose microfibrilada, depositada no laboratório pela técnica de ultrassom e (iv) amostras de bambu (Dendrocalamus Giganteus), extraídas da seção externa e interna do colmo d o bambu. Os resultados são discutidos em conformidade ao rigor metrológico dos componentes estocásticos e determinísticos da incerteza associada às medições realizadas, confirmando que a microscopia de força atômica (AFM), no modo peak force tapping se apresenta como técnica promissora para ser utilizada como ferramenta metrológica para a caracterização de materiais poliméricos na escala nanométrica. / [en] Over the past few decades, more intensely, atomic force microscopy (AFM) has been used in research and development activities, notably for the characterization of materials. Despite the advances and sophistications of the technique, the determination of the modulus of elasticity of polymeric materials remains a challenge given the complexity of characterizing complex materials, commonly generating significant spread in the measurement results. This research presents mappings of the morphology and measurements of the elasticity modulus of commercial cellulose (bamboo and eucalyptus fibers) and lignocellulosic, referenced to already characterized synthetic polymeric materials (considered as standard). Atomic force microscopy (AFM), in the peak force tapping mode, alternatively based on the Derajaguin-Muller-Toporo model, DMT (which is the model incorporated by Bruker in its AFM software) and the Johnson-KendallRobert model, JKR (proposed in this work, using a Matlab algorithm), was used as a technique for measuring the elasticity module of the investigated materials. From the tests performed, it was possible to evaluate the measurement method based on metrological criteria and determine the most appropriate calculation model for the characterization of the investigated materials. For the standard materials used as a reference, whose elasticity modulus values are reported by the respective suppliers (E equal 2.7 more or less 0.1 GPa, for polystyrene and E equal 1.8 GPa, for polyamide), the JKR model proved to be most suitable to support the calculation of the modulus of elasticity. While the JKR model reproduced the manufacturer s value with 6.3 percent, for the case of polystyrene (E equal 2.540754 more or less 0.056 GPa) and with 12.5 percent, for the case of polyamide (E equal 1.680050 more or less 0.041 GPa), the DMT model produced results with deviations greater than 50 percent from the reference value taken as standard reference values. Based on these DMT and JKR models, the work evaluated the elasticity module of other materials, more specifically: (i) cellulose film extracted from eucalyptus; (ii) commercial microfiltered cellulose film; (iii) microfibrillated cellulose film, deposited in the laboratory by and ultrasound technique and (iv) samples of bamboo (Dendrocalamus Giganteus), extracted from the external and internal section of the bamboo stem. The results are discussed in accordance with the metrological rigor of the stochastic and deterministic components of the uncertainty associated with the measurements performed, confirming that the atomic force microscopy (AFM), in the peak force tapping mode, presents itself as a promising technique to be used as a metrological tool for the characterization of polymeric materials at the nanoscale.