Vagabond Shoemakers is one of Europe’s leading design companies within the footwear industry. In the summer of 2019, the project group contacted the company to investigate the possibility to execute an innovation- and development project together. The project would turn into so much more, it would become the beginning of a sustainability work which would lead into a modular shoe for a sustainable future. The sustainability issues within the footwear industry are today bigger than the choice of sustainable materials. There is no good way of recycling or reusing shoes since there is no effective way of separating glue, textiles and rubber form each other. It was from this problem that the foundation of the project was created, is there a possibility to construct a modular shoe? A shoe from the constructions design to facilitate recycling and reuse, through the ability to efficiently separate the parts from each other. Together with Vagabond Shoemakers we would create the foundation of the future footwear industry. A product that would be called Klick-Skon based on the projects Klick-Concept. A product designed to meet the sustainability issues; the result came to be a modular shoe for a sustainable future.

In this project, an additive manufacturing technique called Direct Ink Writing has been used to 3D print structures from polymer solutions containing cellulose acetate. Cellulose acetate is a synthetic compound derived from plants. The intended application involves protein separation filters for medical purposes. The printing has been performed in a lab environment with focus on high resolution, with less than 10 micrometers in fibre size. Glass capillaries with an inner diameter of 3-10 micrometers were used as nozzles. Three-dimensional structures with a height of 100 micrometers and a fibre thickness of 2 micrometers were made. The results indicates that cellulose acetate is a promising polymer for Direct Ink Writing in high resolution. Improvements are needed in the ink design and/or the technical construction of the printer to avoid clogging of the nozzle.

Idag är den största delen av textilierna antingen olje-(60 %) eller bomullsbaserade (30 %). Det är enbart en liten del som är baserade på träfibrer. Ett ökande behov av förnyelsebara textilier föreligger. Samtidigt är ett minskade pappersbehov en drivkraft till att använda de existerande pappersmaskinerna till att tillverka icke vävda textilliknande material. Till skillnad från vävda material kan materialet tillverkas direkt istället för att först tillverka trådar från fibrer. Möjligheter att ta fram textillika material av cellulosafibrer undersöktes. Dynamiska ark gjorda av en blandning av barrmassa och en blandning av barr- och lövmassa med 0, 55 och 70 vikt% polymjölksyra, PLA, tillverkades. Arken pressades ihop två och två med ett mellanlager av Expancel mikrosfärer och bindemedel. Mowilith DM 105 och Primal LT-2949 Emulsion användes som bindemedel. En jämförelse gjordes med ark med enbart bindemedel som mellanlager.   En subjektiv utvärdering av vilket förhållande mellan Expancel mikrosfärer och bindemedel som var bäst lämpad gjordes. För utvärderingen ytbehandlades ett standard papper med 70 vikt% PLA. Den sats med högst koncentration av Expancel mikrosfärer som band bra till bindemedelet valdes. Draghållfastheten testades genom dragprovning enligt ISO 1924-2:1994 men med endast 5 prover istället för 10.  Dragprovningen visade att tillsatsen av Expancel mikrosfärer ökade töjningen hos materialet. Materialen med högst koncentration av PLA gav den mjukaste känslan men också lägst styrka. / Today the main parts of textiles are either oil (60 %) or cotton based (30 %). It is only a small portion which is based on wood fibres. An increasing demand of renewable textiles is forthcoming. At the same time a decreasing demand of paper is one of the motivation of using the existing paper machines to produce nonwoven textile-like materials. Unlike woven fabrics the fabric can be manufactured directly rather than first producing yarn from fibres. Possibilities of developing a textile-like material of cellulose fibres were investigated. Dynamic lab sheets made of a mix of softwood pulp and a mix of softwood and birch pulp with 0, 55 and 70 weight % Poly(lactic acid), PLA, were manufactured. The sheets was pressed together two and two with a middle layer of Expancel microspheres and binder. Mowilith DM 105 and Primal LT-2949 emulsion were used as binders. A comparison was made between sheets with only binder as the middle layer.   A subjective evaluation of which ratio between Expancel microspheres and binder material was best suited was made. For the evaluation a paper containing 70 weight% PLA was coated. The batch with highest concentration of Expancel microspheres, which bonded well to the binder, was chosen. The tensile strength was measured according to ISO 1924-2:1994 but with only 5 test samples instead of 10. The tensile tests showed that with Expancel microspheres resulted in increase of elongation of the material. The materials with the highest concentration of PLA had softest feeling but also lowest strength.

The main intention of this thesis work was to investigate the effect of strain rate on continuum and pre-cracked polymer failure. Low-Density Polyethylene (LDPE) was chosen to study experimentally and numerically. In order to cover wide range of strain rates, four specific strain rates were selected for the uniaxial tensile tests. To perform the tests, cyclic loading and unloading with relaxation was utilized in the room temperature for continuum specimen and for pre-cracked specimen monotonic tensile test till failure was utilized. Through Digital Image Correlation (DIC) the local strain distribution was assessed through the specimen and the deformation was compared with simulation results. Based on the extensive literature review of material models from PolyUMod library among Viscoplastic models, the Three Network Viscoplastic (TNV) model was selected to proceed with the calibration. The motivation behind choosing TNV model is it's capability of capturing load-unload curves, different strain rates as well as non-linear responses. Furthermore, it was seen that among Viscoplastic models, TNV has the lowest average errors which plays a vital role in this case as the accuracy of FE simulation directly depends on the calibration results. From the experimental results it was safe to say that with increasing strain rates LDPE films tend to get stiffer and stronger both in continuum and pre-cracked. Through the calibration it was seen that the predicted curves were in reasonable agreement with experimental ones. Hence,the calibrated model was exported as python script into Abaqus CAE to perform the simulations. The comparison was done and discussed in details between the simulation and experimental data in three orientations; MD (Machine Direction), CD (Cross Direction) and 45 direction.

The interest in renewable natural resources, including plant oils, has become increasingly appealing due to the oil abundance, availability, and wide range of applications for polymers and polymeric materials thereof. In this dissertation, a library of plant oil-based acrylic monomers (POBMs) with a broad range of unsaturation was synthesized using a one-step transesterification. It is demonstrated that the unsaturation degree of plant oil remains preserved during the synthesis and determines the structure and properties of POBMs. The life cycle assessment (LCA) was conducted in this study to evaluate the environmental impact of soybean oil-based acrylic monomer (SBM) production. LCA was applied to provide guidance for SBM synthesis optimization, including the type of catalyst, the ratio between reactants, renewable sources (soybean oil/biodiesel), and solvent recycling. The performed LCA shows the positive effect of the inclusion of the solvent recycling step in the SBM synthesis. This study shows that POBMs behave as conventional vinyl monomers in free radical polymerization and copolymerization. The monomer unsaturation impacts polymerization rate and molecular weight of resulted polymers decreasing as follows: poly(OVM) > poly(SFM) > poly(SBM) > poly(LSM), due allylic termination presented during polymerization. A series of stable POBM-based latexes with high solid content (40-45 %) and monomer conversion (95-97 %) were synthesized using miniemulsion process. The incorporation of POBMs fragments provides the plasticizing effect on the resulting latex polymers, as seen by a noticeable decrease in their glass transition temperature (Tg). The crosslink density of POBM-based latex films follows the linear dependence vs. monomer feed unsaturation, providing a tool for controlling latex mechanical properties, including hardness, toughness, Young's modulus, etc. Besides, the presence of highly hydrophobic POBM fragments enhances water resistivity of latex coatings and films. Following the "greener" vector of research, a variety of stable latexes from high oleic soybean oil-based monomer (HOSBM) and cardanol, eugenol, and guaiacol derivatives were synthesized in miniemulsion. Resulting polymeric materials advantageously combine flexibility provided by HOSBM fragments with strength facilitated by aromatic biobased units.

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Polymeric materials are popular in civil infrastructure due to their durability, strength, and resistance to corrosion and environmental degradation. However, the long-term performance of such materials in civil infrastructure is still being researched and investigated. This thesis will focus on the long-term performance of two civil infrastructure applications: 1) high-density polyethylene (HDPE) above-ground storage tanks (AST) and 2) silicone and self-healing polymeric concrete sealants. HDPE is a strong and durable plastic material that is commonly used to store a wide range of liquids ASTs. Currently, there are no established protocols for carrying out non-destructive testing (NDT) and assessment of HDPE ASTs for regular inspections, so this study investigated the viability of using infrared thermography (IRT) and ultrasonic testing (UT) for routine inspection. The study discovered that environmental parameters, such as temperature, wind, and humidity, can affect IRT accuracy, and that a proper heating-cooling cycle can aid in defect detection. Concrete joints in pavement systems are often susceptible to deterioration. They are engineered cracks that enable concrete slabs to expand and contract in response to temperature. They serve the dual purpose of preventing water infiltration and improving ride quality, while extending the pavement's service life. Bridge joints, in particular, are susceptible to water and liquid penetration, which can result in extensive damage over time. By applying sealants to these connections, concrete structures can be protected from such damage, thereby extending their service life. Consequently, a better comprehension of sealant performance and additional research are required to develop effective solutions to address these issues and ensure the safety and longevity of concrete structures prone to cracking. In this study, samples of the two commercial silicone joint sealants were sandwiched between Portland cement mortar specimens and tested using a specially designed fixture to imitate the fatigue performance of the joint under simulated field conditions. The results of the study indicated that the fatigue life of the two silicone sealants were different, with Sealant 2 showed better performance than Sealant 1. Both sealants exhibited adhesive failure initiating debonding along the weak interface of cement mortar cube and joint sealant. The results of commercial sealants are then compared with self-healing polysulfide sealants. This indicates that the performance of sealants can vary, and additional research may be required to develop effective solutions to address these issues. / Master of Science / Polymeric materials are widely utilized in construction due to their durability, strength, and resistance to corrosion and environmental degradation. However, the long-term performance of these materials in civil infrastructure is still under investigation. This thesis specifically examines the long-term performance of two civil infrastructure applications: 1) high-density polyethylene (HDPE) above-ground storage tanks (ASTs) and 2) silicone and self-healing polymeric concrete sealants. HDPE is a robust and durable plastic material commonly employed for storing various liquids in ASTs. Currently, there are no established protocols for conducting non-destructive testing (NDT) and assessment of HDPE ASTs during regular inspections. Therefore, this study investigates the viability of utilizing infrared thermography (IRT) and ultrasonic testing (UT) for routine inspections. The findings reveal that environmental factors such as temperature, wind, and humidity can impact the accuracy of IRT, and implementing a proper heating-cooling cycle can help in detecting such defects inside the tank structure. Concrete joints in pavement systems are susceptible to deterioration. These engineered cracks allow concrete slabs to expand and contract in response to temperature changes, while preventing water infiltration and enhancing ride quality, thus prolonging the pavement's service life. Bridge joints, in particular, are prone to water and liquid penetration, leading to extensive damage over time. Applying sealants to these connections safeguards concrete structures, extending their service life. Consequently, understanding sealant performance and conducting further research are crucial for developing effective solutions to address these issues and ensure the safety and durability of concrete structures prone to cracking. This study involves testing two commercially available silicone joint sealants by sandwiching them between Portland cement mortar specimens. A specially designed fixture is employed to simulate the fatigue performance of joints under field-like conditions. The performance of commercial sealants was also compared with self-healing polysulfide sealants. These findings highlight the variability in sealant performance, emphasizing the need for additional research to develop effective solutions.

The size effect in the thermo-mechanical behavior of polymeric materials is a critically important phenomenon and has been the subject of many researches in past decades. For example, polystyrene (PS), a widely used polymeric material, is brittle at the bulk state. When the dimensions decreases to the nanoscale, such as PS in nanofibers, their ductility becomes orders higher than their bulk state. In recent years a number of diverse applications, such as scaffolds in tissue engineering, drug delivery devices, as well as soft robotics, are designed by utilizing the unique properties of polymers at nanoscale. However, the inside mechanism of the size dependency in polymeric materials are still not clear yet. In this dissertation, systematic computational and experimental studies are made in order to understand the origins of the size effect for one- and two-dimensional polymeric materials. This framework is also expanded to investigate the size-dependent multi-physics response of functional polymeric materials (shape memory polymers) which are actuated by high-intensity focused ultrasound (HIFU). Our computational studies are based on molecular dynamic (MD) simulations at the atomistic scale, and experimentally-validated finite element models at the bulk level. From bottom-up direction, molecular dynamics can reveal the mechanisms of the size effect in polymers at molecular level, and help predict properties of the bulk materials. In this research, MD simulations are performed to track the origins of the size-effect in the mechanical properties of PE and PS nanofibers. In addition, the size-dependent thermal response of functional polymeric films is also studied at the atomistic scale by utilizing molecular dynamics simulations to predict the thermal properties and actuation mechanisms in these materials when subjected to HIFU fields. From top-down direction, experiments and finite element analysis, are also conducted in this research. An experimentally-validated finite element framework is built to study the mechanical response of shape memory polymers (SMPs) triggered by HIFU. As an external trail towards application fields, a SMP composite with enhanced shape memory ability and also a two-way SMP are synthesized. A smart gripper and also a self-rolling structure are designed by using these SMPs, which approves that these SMPs are good components in designing soft robotics. Finally, The influence of evaporation during fiber forming process is investigated by molecular dynamics simulation. It is found that the formation of the microstructure of polymeric fibers at nanoscale depends on the balance of stretching force and evaporation rate when the fiber is forming. / Doctor of Philosophy / Thermomechanical properties of a thin fiber, a thin film and a cube made of a polymer are significantly different. Although, based on the extensive research that has been performed in recent years our understanding of this size-dependency is advanced to a great degree in the past decades, there are still many unanswered basic questions that can only be addressed by performing computational and experimental investigation at different length scales, from atomistic up to bulk level in polymers. In this research we target exploring some unknown aspects of the size dependency in the thermomechanical properties of polymers by investigating their deformation mechanisms at different length scales. As the first step, we will investigate the mechanical properties of polymeric fibers. For these fibers, the mechanical properties are strongly connected to the fiber's diameter. The prevailing hypothesis is that this size dependency is closely related to the thickness of the surface layer of the nanofibers. Our results show some unknown origins behind the size dependency of the mechanical properties in polyethylene (PE) and polystyrene (PS) nanofibers, which originate from the deformation mechanisms at the atomistic scale. In addition, not just the mechanical properties, the thermal properties and response of functional polymers subjected to an external stimulation are also related to their size. For example, the thermal conductivity of a fiber, a sheet and a cube may be significantly different. Our study shows the thermal responses of different polymers triggered by ultrasound are also different. The size and the type of the polymers will both have influence on the final temperature in the polymeric materials, when the polymeric materials are heated by same ultrasound source. We also have applied our computational and experimental frameworks to investigate this phenomenon. In addition, we also used a new shape memory polymer composite and a two-way shape memory polymer on designing soft robotics-like structures. Overall this research indicates that both mechanical response and thermal responses of polymers are highly related to their dimension. Taking advantage of these unique size effects, and by tailoring this property, diverse devices can be made for being used in a broad range of applications.

A cold extrusion process has been developed to tailor a porous structure from polymeric waste. The use of an extruder to manufacture acoustic materials from recycled waste is a novel idea and the author is not aware of any similar attempts. The extruder conveys and mixes the particulates with a reacting binder. The end result is the continuous production of bound particulates through which a controlled amount of carbon dioxide gas that is evolved during the reaction is used to give the desired acoustic properties. The cold extrusion process is a low energy consuming process that reprocesses the post manufacturing waste into new vibro-acoustic products that can be used to meet the growing public expectations for a quieter environment. The acoustical properties of the developed products are modelled using Pade approximation and Johnson-Champoux-Allard models. Applications for the developed products are widespread and include acoustic underlay, insulation and panels in buildings, noise barriers for motorways and railway tracks, acoustic insulation in commercial appliances and transport vehicles.

Ao final da década de 1980, pesquisadores da empresa Eastman Kodak anunciaram as propriedades eletroluminescentes de materiais orgânicos não poliméricos. Seguindo essa linha, em 1990, um grupo de pesquisadores ingleses demonstrou propriedades semelhantes para os polímeros, utilizando-os como elementos ativos de dispositivos emissores de luz. Era este o início de uma nova área de pesquisa que tinha interface na eletrônica e nos novos semicondutores poliméricos. Surgiram os chamados polímeros luminescentes - resultado das descobertas das propriedades semicondutoras dos polímeros e copolímeros, blendas e heteroestruturas orgânico-inorgânicas. Os materiais semicondutores poliméricos apresentam diversas vantagens associadas à sua característica de fácil processamento e baixo custo de produção. Podem ser utilizados na forma de filmes finos que têm boas propriedades mecânicas e que permitem a sua utilização em substratos flexíveis. Diversas empresas como Philips, Sony, Pioneer, DuPont, Kodak e Uniax têm investido fortemente em pesquisa e desenvolvimento de dispositivos eletroluminescentes, memórias, sensores de imagem e outros sensores que aproveitam as propriedades dos polímeros semicondutores. A radiação, numa variada faixa de comprimentos de onda, pode afetar as propriedades de alguns desses polímeros semicondutores. A característica de material semicondutor, inerente a esses materiais, pode ser degradada por efeito de foto-oxidação que pode ser estimulado pela exposição à radiação. Surge a possibilidade de desenvolver dispositivos baseados em polímeros semicondutores para uso em detectores de radiação. Este trabalho consiste num estudo de desenvolvimento de dosímetros poliméricos de radiação para a faixa de comprimento de onda entre 400 nm e 500 nm, especificamente usada em ambientes hospitalares no tratamento intensivo de neonatos. Com o objetivo descrito, foi realizado o estudo de substratos adequados para a finalidade desejada, o desenvolvimento de um processo de deposição para os dispositivos de filmes-finos e o estudo da influência da radiação na faixa do ultravioleta-visível (UV-Vis) em suas propriedades. Das diversas técnicas de deposição de filmes finos existentes, foi selecionada para este estudo, a de deposição por jato de tinta (\"inkjet printing\") devido às suas características de simplicidade, potencial custo baixo e, principalmente, o menor nível de perda do polímero a ser depositado, já que a referida técnica permite a deposição de quantidades mínimas do material. Como material ativo foi selecionado um semicondutor polimérico da família dos polifluorenos, devido ao seu relativamente fácil manuseio. Pesquisadores da área, cada vez mais, acreditam que a impressão por jato de tinta seja uma das técnicas de deposição mais promissoras para a produção em grande escala. O objetivo desta pesquisa é contribuir com um novo instrumento a ser usado no monitoramento da irradiação no tratamento fototerápico da hiperbilirrubinemia no ambiente da neonatologia hospitalar. Atualmente os bebês recém-nascidos são tratados com empirismo considerável tendo em conta não haver procedimentos de controle para a dose da irradiação aplicada ao neonato nas incubadora neonatal das maternidades. Os riscos de hiperbilirrubinemia severa do neonato incluem a possibilidade de surdez, de paralisia cerebral ou mesmo de lesão cerebral em casos extremos. A observada Icterícia pode estar ligada à imaturidade do fígado do bebê. A bilirubinemia é muito freqüente em neonatos e precisa ser tratada para a redução dos citados riscos. O tratamento mais comum é a fototerapia com radiação na faixa do UV-próximo/azul. A fototerapia é realizada por várias sessões de muitas horas que dependem do nível de hiperbilirrubinemia no sangue, TBS (Total Bilirrubine Serum) do bebê. A hiperbilirrubinemia é crítica quando seu nível for igual ou maior que 428 micromol/litro ou 25 mg/dL (Referencia - Previsão e prevenção de hiperbilirrubinemia de neonatal extremo, T.B., Newman et al., Arco Pediatr Adolesc Med/Vol 154, Nov. 2000 pp 1140-1147). Além de permitir reduzir o empirismo do tratamento com o uso de um dosímetro para a faixa de radiação em tela, este pode ser usado para avaliar a condição da fonte de radiação específica de luz usada neste tipo de tratamento. O dosímetro proposto, como instrumento adicional para os neonatologistas poderá monitorar as doses de radiação aplicada durante a fototerapia e evitar excessos, reduzindo o tempo no protocolo de tratamento neonatal. / At the end of the 1980s, researchers from Eastman Kodak announced the electroluminescent properties of non-polymeric organic materials. At the beginning of the 1990s, researchers from the UK showed similar properties of organic polymers, using them as active elements in light emitting devices. It was the beginning of a new research area interfacing the electronics and the new polymeric semiconductors. As a result of the findings on the semiconducting properties of polymers and copolymers, blends and organic-inorganic heterostructures, a new class of materials became the research subject of several groups. Polymer semiconductors exhibit several advantages like simple processing and low production cost. They can be utilized as thin-films with good mechanical properties for use in flexible substrates. Several high-tech enterprises like Philips, Sony, Pioneer, DuPont, Kodak and Uniax are investing strongly in the research and development of such materials and devices, including memories, image sensors, light-emmiting devices, among others. Radiation in a very broad range of wavelengths can affect characteristics of some semiconductor polymers. Their inherent semiconducting feature can be degraded by the photo-oxidation effect, activated by radiation exposition. This suggests the possibility of the development of semiconductor polymer based radiation sensing devices. This work deals with a study of radiation dosimeters for the wavelength range of 400 nm to 500 nm, specifically important at the maternity hospitals in the therapy of newborn babies. To cope with this objective, the study of adequate substrates, development of suitable deposition process for the thin-film devices and study of its properties changes with radiation in the ultraviolet-visible (UV-Vis) range was done. From the different thin-film deposition techniques, the inkjet deposition technique was selected for this study thanks to its production simplicity, potential low cost an, mainly, because it permits the deposition of minute amounts of material, leading to very little material losses. As the active material a polymeric semiconductor of the fluorene family was selected thanks to its easy processing. Researchers of this area, more and more, believe that the Inkjet Printing is one of the very promising deposition techniques for mass production of those devices. The aim of this research is to offer a new tool to be used in the monitor of the irradiation in the phototherapy for severe hyperbilirubinemia of newborn babies. In most cases newborn babies are treated with a considerably empiric protocol considering the inexistence of procedures to control the radiation doses in the treatments. The risks of extreme neonatal hyperbilirubinemia include possibility of deafness, cerebral palsy or brain damage in extreme cases. Jaundice may be due to the immaturity of baby\'s liver. Bilirubinemia is most frequent in newborn and must be treated to reduce such risks. The most common treatment is phototherapy with nearUV-blue radiation. Phototherapy is accomplished by several sessions of many hours depending on the Total Bilirubin Serum (TBS) found in the baby blood. Hyperbilirubinemia is very dangerous to the near-term newborn when its level is equal or greater than 428 micromol/liter or 25 mg/dL (Reference Prediction and prevention of extreme neonatal hyperbilirubinemia, T.B., Newman et al., Arch Pediatr Adolesc Med/Vol 154, Nov. 2000 pp 1140-1147). Besides reducing the empiric treatments based on the nearUV-blue radiation, the use of a sensor can be important to evaluate the condition of the specific type of lamp used in the treatments. The proposed dosimeter can be an additional instrument for the neonatologists to be used in the determination of the phototherapy radiation dose, thus reducing, in the medical protocol, the jaundice treatment time.