<p> This thesis provides examples of new Si-based polymeric materials in three parts. The rapid evolution of hydrogen gas was observed after the combination of an α- or β-hydroxy carboxylic acid with an alkoxyhydrosilane. This unusual reactivity is interpreted to arise from the cooperative nucleophilic attack of the hydroxy group at silicon and the electrophilic attack of the acid proton at the Si-H bond. These systems further react to produce modified sol-gel materials in which the acid units were incorporated into the matrix.</p> <p> The reactions of tetraethoxysilane, (TEOS) and α-hydroxy acids similarly produced modified sol-gels (in solution, DMSO) and solids (precipitated from THF). The reaction kinetics were followed in these systems using 29Si NMR. Extensive characterisation of our sol-gels was carried out by the use of various NMR techniques, FT-IR, elemental analysis and thermal methods of solids characterisation (TGA, DTA, and DSC).</p> <p> Silicones containing vinylsilane units were prepared in order to examine the silicon β-effect in a polymeric system for the first time. The addition of bromine to these systems unexpectedly resulted in no reaction unless vigorous conditions were used. Steric factors as shown by molecular modeling are attributed to this lack of reactivity. Although many silicone systems were studied where more sterically "open" vinylsilanes were present these steric problems could not be overcome.</p> / Thesis / Master of Science (MSc)

Artificial  spider  webs  are  a  challenge  for  the  special  effects  companies.   The natural  spider webs  are  displaying  incredible  mechanical  properties  combined with  a  low  density  and  a  high stickiness making them hard to reproduce. Throughout this project the aim is to produce artificial spider  webs  using  a specific  manufacturing  method,  pouring  a  mix  of  polymer  and  Naphtha  oil into  water  to  form  the  webs.   This  method  was  used  in  previous  cinematic applications  giving outstanding results for the artificial spider webs.  Unfortunately, due to the loss of it, the specific parameters,  tools and raw materials have to be found.  A material selection is given leading to a specific choice of thermoplastic polymers.  The selected material are then tested manually so they can be listed depending on the results obtained.  Finally, the most promising material seems to be TPU, thermoplastic polyurethane;  thanks to its excellent mechanical properties and good visual aspect. / Konstgjord  spindelväv  är  en  utmaning  för  specialeffektföretag.   De  naturliga spindelnäten visar  otroliga  mekaniska  egenskaper  i  kombination  med  låg densitet  och  hög  klibbighet  vilket gör  dem  svåra  att  reproducera.    Under hela  detta  projekt  är  målet  att  producera  konstgjord spindelväv med hjälp av en specifik tillverkningsmetod, hälla en blandning av polymer och naftaolja i vatten för att bilda näten.  Denna metod användes i tidigare filmiska applikationer och gav enastående resultat för de konstgjorda spindelnäten.  Tyvärr, på grund av förlusten av det, måste de specifika parametrarna, verktygen och råvarorna hittas. Ett materialval ges vilket leder till ett specifikt val av termoplastiska polymerer. Det valda materialet testas sedan manuellt så att de kan listas beroende på de erhållna resultaten.  Slutligen verkar det mest lovande materialet vara TPU, termoplastisk polyuretan; på grund av dess utmärkta mekaniska egenskaper och bra visuella aspekt.

No / A large deformation, rate dependent model is applied to high temperature stretching of polyethylene. The theory is physically motivated, consisting of a model of a network of chain molecules to represent regions dominated by amorphous polymer, with embedded rigid spheres to introduce strain concentration similar to that caused by hard crystalline regions. Dependence on time and rate is introduced via shear stress driven diminution of the sphere radii. Experimentally, the rate dependence of the stress is such that, under tensile deformation, there is no necking associated with the initial yield point. Necking occurs at higher strains; this is associated with a weakening of rate dependence with increasing strain, which is a natural feature of the theory. It provides a realistic model of large tensile deformations, which in general involve the evolution of necking instabilities. It is implemented in a finite element scheme by using the package ABAQUS.

In-situ composites based on self-reinforcing blends of engineering thermoplastics and thermotropic liquid crystalline polymers (TLCPs) are recently developed, innovative polymeric materials, which have been reported to exhibit outstanding property profiles. These profiles include superior mechanical properties, excellent thermal and dimensional stabilities at high temperatures, and improved melt processabilities. Such characteristics make in-situ composites very attractive as performance polymer-based materials for tribological applications. To date, a thorough investigation of the tribology of in-situ composites has not yet been undertaken and, thus, the potential of these composites as performance tribomaterials has not been effectively assessed. The present research addresses this issue. An investigation is carried into the elevated temperature tribology of in-situ composite systems based on binary blends of Polyetheretherketone (PEEK) and HX-1000, a commercially available TLCP, as well as on ternary blends of PEEK, Polyetherimide (PEI) and HX -1000. The specific tribological phenomenon investigated is unlubricated sliding. Friction and wear measurements are performed at selected temperatures in the range from 20°C to 250 °C using a pin-on-disk tribometer. Dynamic mechanical thermal analysis and morphological studies are carried out in conjunction with the tribological evaluation. The impact of operating temperature on tribological performance as well as active friction and wear mechanisms are discussed in terms of thermally activated molecular relaxation processes and the solid state morphology of the composite systems investigated. Basic knowledge of the way in which the structure, mechanical properties and tribological behavior of in-situ composites are interrelated is gained. Results from this research point to the validity of the concept of TLCP in-situ reinforcement as a means to produce thermoplastic-based performance tribomaterials. / Ph. D.

Informationen om att det bränns ull i mängder samtidigt som vi importerar ull talar sitt tydligaspråk att något behöver göras. Ull som är ett hållbart och 100% förnybart material med bådehistoriska och fantastiska egenskaper, vilket gör att det är ett enormt resursslöseri att brännaull som om det vore skräp. Det finns många eldsjälar inom fårbranchen som arbetar för atthitta lösningar för dessa problem. Ullklassificering, att ta fram en nationell agenda överullhantering och försök att öka intresset för ull i allmänhet står på agendan. Utifrån ett hållbarhetsperspektiv såväl som ett personligt intresse och utifrån mina år somstylist har jag undersökt ullens sinnliga egenskaper för att hitta nya materialupplevelser i ettav världens äldsta textila material. Klimatfrågan som är högst aktuell, vilket vi alla på ett ellerannat sätt måste förhålla oss till, samt mitt mål att göra min forskning tillgänglig för alla, göratt mitt arbete har relevans utifrån ett hållbart, samhällsmässigt och kunskapsmässigtperspektiv. Utifrån en materialdriven design, där materialets mening står för att väva in denkänslomässiga kopplingen svensk ull, vill jag med konstnärlig ansats ta mig an arbetet i attutforska, utvärdera och ifrågasätta mig själv. Basen i hela mitt arbete är den materialdrivnaprocessen där jag varvar material och användartester för att bidra med nyamaterialupplevelser av ull. Jag hoppas att mitt arbete gör att vi ser med nya ögon på ull ochatt våra associationer till svensk ull inte enbart ses som en stickad tjocktröja eller ett parlovikkavantar från en gången tid. Jag vill vidga perspektiv och inspirera till att se möjligheter iden materialskatt vi har runt hörnet. / The information that wool is burned in quantities while we are importing wool speaks its clearlanguage, something needs to be done. Wool, which is a durable and 100% renewablematerial with both historical connections as well as fantastic properties, is a huge waste ofresources to burn as if it were rubbish. From a sustainability perspective as well as a personal interest, based on my years as astylist, I have investigated the sensual properties of the wool to find new materialexperiences in one of the world's oldest textile materials. The climate issue that is mostup-to-date, which we all have to relate to in one way or another, and that I want to make myresearch available to everyone, means that my work is relevant from a sustainabilityperspective. I have worked from a material-driven design, where the meaning of the material has beenimportant in order to weave the emotional connection to a material. With an artisticapproach, I wanted to take on my work in exploring, evaluating and questioning myself andmy work in a material-driven process, in which I turn materials and user tests to contributewith new material experiences of wool. I hope that my work contributes to seeing Swedishwool with new eyes. With new associations and perspectives. To see opportunities insteadof impossibilities.

Stimuli-responsive drug delivery materials release their payloads in response to physiological or external cues and are widely reported for stimuli such as pH, temperature, ionic strength, electrical potential, or applied magnetic field. While a handful of reports exist on materials responsive to mechanical stimuli, this area receives considerably less attention. This dissertation therefore explores three-dimensional networks and polymer-metal composites as mechanoresponsive biomaterials by using mechanical force to either trigger the release of entrapped agents or change the conformation of implants. At the nanoscale, shear is demonstrated as a mechanical stimulus for the release of a monoclonal antibody from nanofibrous, low molecular weight hydrogels formed from bio-inspired small molecule gelators. Using their self-healing, shear-thinning properties, mechanoresponsive neutralization of tumor necrosis factor alpha (TNFα) in a cell culture bioassay is achieved, suggesting utility for treating rheumatoid arthritis. Reaching the microscale, mechanical considerations are incorporated within the design of cisplatin-loaded meshes for sustained local drug delivery, which are fabricated through electrospinning a blend of polycaprolactone and poly(caprolactone-co-glycerol monostearate). These meshes are compliant, amenable to stapling/suturing, and they exhibit bulk superhydrophobicity (i.e., extraordinary resistance to wetting), which sustains release of cisplatin >90 days in vitro and significantly delays tumor recurrence in an in vivo murine lung cancer resection model. This polymer chemistry/processing strategy is then generalized by applying it to the poly(lactide-co-glycolide) family of biomedical polymers. As a macroscopic approach, a tunable, tension-responsive multilayered drug delivery device is developed, which consists of a water-absorbent core flanked by two superhydrophobic microparticle coatings. Applied strain initiates coating fracture to cause core hydration and subsequent drug release, with rates dependent on strain magnitude. Finally, macroscopic, shape-changing polymer-composite materials are developed to improve the current functionality of breast biopsy markers. This shape change provides a means to prevent marker migration from its intended site—a current clinical problem. In summary, mechanoresponsive systems are described, ranging from the nano- to macroscopic scale, for applications in drug delivery and biomedical devices. These studies add to the nascent field of mechanoresponsive biomedical materials and the arsenal of drug delivery techniques required to combat cancer and other medical ailments. / 2017-10-27T00:00:00Z

With the population growing gradually and economy booming in the world, the need of textile product accordingly increases rapidly, which results in the big generation of textile waste. The disposal of textile waste brings in many adverse effects on environment, such as the landfill occupation. The production of textile product itself also causes much environmental concerning. In order to cope with the increasing textile waste and reduce the pressure of waste management, waste prevention is primary, as well as effective choice. The prevention of waste from textile can return ideal revenue from economic, social and environmental aspects. So many countries have conducted some researches and practices on the prevention of waste from textile. Sweden also has some existed prevention measures. But these prevention measures mainly focus on two stakeholders: consumer and charitable organization.  Associated with the practical situation in Sweden, some existed prevention measures are transferred to the Swedish circumstance and then suggest a new prevention scheme about textile waste in Sweden. The suggested prevention scheme is based on four stakeholders’ (designer, retailer, consumer, charitable organization) point of view.

The Shibori technique on modern furniture fabrics. A study in the name of chance. / <p>Presentation-framläggning via zoom-länk.</p>

Charge transport, charging, and subsequent electrostatic discharge due to interactions with the space environment are primary concerns of spacecraft designers. Developing a physical understanding of the interactions of charge with the multitude of materials that spacecraft are composed of is a critical step in understanding and mitigating both short-term and long-term spacecraft degradation. In particular, the study of charge transport in highly insulating materials is critical as they store charge longer, with higher capacity, and with greater destructive capability than other materials.The Utah State University Materials Physics Group, with the funding of the NASA James Webb Space Telescope project and Rocky Mountain Space Consortium, have developed a complete and consistent theoretical model that predicts short-term and long-term storage capabilities based on physical material parameters. This model is applicable across a wide range of experimental systems designed to test specific behaviors that characterize charging phenomena.Modeling and understanding the complex relationships between the spacecraft and its surroundings are fundamentally based on detailed knowledge of how individual materials store and transport charge. The ability to better understand these effects will help make exploring the edges of the universe more stable, reliable, and economic.

No / Polymeric materials are described which have a bioflavonoid coating, the bioflavonoid content of the coating comprising at least naringin and neohesperidin. The use of such coated polymeric materials is also described as well as the process for making the coated polymeric materials.