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This thesis describes studies of the relationship between the molecular structure of a range of organophosphorus-based polymer additives and their ability to confer intumescent flame retardant properties on the resulting polymers. The development of intumescent fire retardants is discussed along with the principles of flame retardancy in general. Much of the work centred around the chemistry of a key starting material, pentaerythritol phosphate (PEPA). This compound was found to be less reactive than expected, due to a combination of its neopentyl type structure and the electron withdrawing effect of the phosphoric ester functionality. Various derivatives of PEPA were synthesised, most containing reactive functional groups which facilitated future development of the compound. The derivatives containing no reactive groups were investigated for their intumescent behaviour in their own right. Derivatives of PEPA containing an acidic functionality were utilised in the production of intumescent salt systems using cations with a high nitrogen content in the form of s-triazines. The most promising was the trimethylolmelamine salt of a bis-PEPA derivative of phosphoric acid, which, on testing, proved to be more effective than the current "state of the art" intumescent additive. Metal salts of acidic PEPA-derivatives were also investigated. Derivatives of PEPA containing a carbon-carbon double bond were investigated for their potential to polymerise and thus form more stable additives. Only one such polymer was successfully synthesised, that being poly (PEPA methacrylate). Despite being non-intumescent, due to its high thermal stability this polymer has potential as a flame retardant additive. The monomer was found to copolymerise with methyl methacrylate to form a polymer of high thermal stability. When investigating the relationship between the molecular structure of the compounds developed and their intumescent behaviour, it was observed that only compounds containing an ionisable hydrogen atom exhibited intumescent decomposition on pyrolysis.

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Thin films of the fullerenes PC60BM and PC70BM and the non-fullerene N2200, three popular electron acceptor materials in organic photovoltaics, have been studied, using both the Kelvin probe method as well as ultraviolet photoelectron spectroscopy. With these methods the work function was measured, as well as the highest occupied molecular orbital (HOMO) onset. Additionally band bending effects were studied by illuminating the samples while measuring the work function with the Kelvin probe so called surface photovoltage. Sample of each material was exposed to either air and simulated sunlight or N2 and simulated sunlight, for different length of time, to observe how the materials work function evolves after exposure to the different conditions. It was observed that, as expected from previous studies, that PC60BM was less photo-stable than PC70BM. Additionally, the work function of PC60BM changed significantly by storage in N2. Each material after exposure for 24h to air and light, was annealed and measured with the Kelvin probe. A restoring effect was observed,  for the non-fullerene material N2200. All three materials developed an increasing surface photovoltage, which suggest increased band bending, when exposed to air and light, indicating that due phot-oxidization, charges are redistributed at the surface of the film. The fullerenes showed a larger surface photovoltage effect than the non-fullerene materials. A difference between the work function values obtained from the Kelvin probe method and the ultraviolet photoelectron spectroscopy could be seen, however the exact reason for this couldn't be isolated within this thesis, but was discussed.

Tendons transfer forces from muscle to bone and allow the locomotion of the body. However, tendons, especially for tendons in the hand, get lacerated commonly in different injuries and the healing of tendon within the narrow channel in the hand will normally lead to tendon adhesion and sacrificed tendon mechanics. Researches have been focused on addressing tendon adhesion prevention but neglecting healed tendon mechanics. This thesis discusses the principles and challenges in the design of biomaterials regarding flexor tendon repair with advanced polymer chemistry and materials science. A rational platform, not only focusing on the prevention of tendon adhesion, but devoting more efforts on final healed properties of tendons via implementing glycopolymer-based materials to guide tendon cells attachment, was designed, fabricated and characterized. Controlled ring opening polymerizations and atom transfer radical polymerizations were combined for the synthesis of miktoarm well-defined block copolymers. Para-fluorine click reactions were then implemented to afford glycopolymers with glucose units. Obtained copolymers were transformed into 3D membranes constituting a porous fibrous structure utilizing electrospinning. The aligned structure was then fabricated to optimize the mechanics of these materials for practical application as well as reconstruct normal tendon physiological structure. Lastly, the toxicity, cell affinity and cell activity of obtained materials were evaluated in vitro employing tendon cells as a cell line to confirm the suitability of obtained platforms for flexor tendon repair.

The following report refers to a thesis project at the undergraduate level in innovation and product design, at Mälardalen university. The project has been carried out for Mälardalen University's workshop, which needs a machine that can recycle PLA waste. The work involved developing a concept that is economically defensible and performs at the same level as existing machines in the surrounding price range. The problem statements to be answered are the following:• What components are required for extrusion of PLA?• Which inclination is the most efficient for extrusion of PLA?The product development process described in Ulrich and Eppinger (2014), the 6 product development phases, has been the basis for the execution of this thesis project. The client's wishes, which were divided into two different categories, absolute requirements, and desirable requirements, were fulfilled in part through a theoretical concept that will later result in a physical concept.A decision matrix was drawn up to be able to decide which concept the thesis project should continue with. Concept 3 became the concept that received the most points in the matrix. The concept was based on different inclinations of the machine, and which would be most efficient in terms of time and as few components as possible. This concept was further developed in the CAD program Solidworks with a vertical setup with all the components. The vertical design means that the PLA wire does not need to be actively cooled but is instead cooled in room temperature. The total cost for the components that were ordered was around SEK 6400 (excluding what the school already has). In terms of price, this is far below the machine that is between the cheapest and the most expensive machine.The theoretical part of the work has been delivered to Henrik Lekryd and it has been well received. But no physical machine has yet been built because the ordered components have had a long delivery time. This will happen in the near future.The second question has not been answered either, as this requires a physical machine to finally calculate the machine's capacity in the selected slope (vertically). The vertical slope was chosen so that there is not a need for additional components for cooling filaments, such as water baths or fans.For further work, it is recommended, among other things, that a physical prototype is built to see what problems may arise and see the shortcomings in the selected components. A gearbox may need to be used to not overload the stepper motor. For a more durable and stable machine, metal is a better material to build the frame of, than the theoretically proposed material, MDF. / Följande rapport är avser ett examensarbete som har utförts på grundnivå på högskoleingenjörsprogrammet, inom innovation och produktdesign vid Mälardalens Högskola. Projektarbetet har utförts åt Mälardalens Högskolas verkstad som är i behov en maskin som kan återvinna PLA-skräp. Arbetet innebar att ta fram ett koncept som är ekonomiskt försvarbart och presterar på samma nivå som befintliga maskiner i kringliggande prisklass. De frågeställningar som ska besvaras är följande:• Vilka komponenter krävs för extrudering av PLA?• Vilken lutning är mest effektiv för extrudering av PLA?Produktutvecklingsprocessen som beskrivs i Ulrich och Eppinger (2014), de 6 produktutvecklingsfaserna, har varit grunden för utförandet av detta projektarbete. Uppdragsgivarens önskemål som delades upp i två olika kategorier, absoluta krav och önskvärda krav, uppfylldes delvis genom ett teoretiskt koncept som i senare skede ska resultera i ett fysiskt koncept.En beslutmatris uträttades för att kunna ta ett beslut kring vilket koncept som projektarbetet ska fortsätta med. Koncept 3 blev det koncept som fick flest poäng i matrisen. Koncepten byggde på olika lutningar av maskinen och vilket som skulle vara mest effektivt tidsmässigt och med så få komponenter som möjligt. Detta koncept vidareutvecklades i CAD-programmet Solidworks med en vertikal uppsättning av alla komponenter. Den vertikala designen innebär att filamentet inte behöver kylas ner aktivt, utan den kyls ner i rumstemperatur. Den totala kostnaden för de komponenter som beställdes blev cirka 6400kr (exklusiv det som skolan redan har). Detta hamnar prismässigt, långt under den maskin som är mellan den billigaste och den dyraste maskinen.Den teoretiska delen av arbetet har levererats till Henrik Lekryd och det har mottagits väl. Men någon fysisk maskin har ännu inte byggts eftersom de beställda komponenterna har haft lång leveranstid. Detta kommer att ske inom en snar framtid.Den andra frågeställning har inte heller besvarats eftersom för detta krävs en fysisk maskin för att slutligen räkna ut maskinen kapacitet i den valda lutningen (vertikalt). Den vertikala lutningen valdes för att inte behöva använda fler komponenter för kylning av filament, såsom vattenbad eller fläkt.För fortsatt arbete rekommenderas bland annat att en fysisk prototyp byggs för att se vilka problem som kan dyka upp och se bristerna i de valda komponenterna. En växellåda kan komma att behöva användas för att inte belasta stegmotorn. För en tåligare och stadigare maskin är metall ett bättre material att bygga ramen av än det i teoretiskt föreslagna materialet, MDF.

The aim of the thesis was to recycle a common carpet waste containing polyamide 6 (PA6) and polypropylene (PP) polymers with thermomechanical recycling. The produced products were compared to neat polymer materials. The recycled material underwent the thermomechanical process which includes shredding and extruding. The created filament was analyzed using various analysis techniques including FTIR, SEM, DSC and tensile testing for the mechanical properties. The filament was later evaluated with a 3D printer to see if a product could be made from the material. Filament containing recycled carpet material was used to create a 3D printed product, thus the method seems promising. The results from the structural analysis techniques showed that degradation of the polymers occurred after multiple recycling cycles, mostly of the PA6 polymer. The mechanical properties with the addition of recycled carpet to a blend of neat materials show similar properties when compared to only neat material. In conclusion, it is possible to 3D print recycled carp inted product so the method seems viable for future applications. / Syftet med avhandlingen var att återvinna en vanlig matta som innehåller polyamid-6- och polypropenpolymerer med termomekanisk återvinning och jämföra produkten med rena polymermaterial. Det återvunna materialet tillverkades med den termomekaniska processen som inkluderar malning och strängsprutning (extrudering). Filamentet analyseras med olika analystekniker inklusive FTIR, SEM, DSC och dragprovning för mekaniska egenskaper. Filamentet testas sedan med en 3D-skrivare för att se om en produkt kan tillverkas av materialet. Filamentet med återvunnen matta användes för att skapa en 3D-skriven produkt, därför verkar metoden lovande. Resultaten från analysteknikerna visade polymererna bröts ner efter flera återvinningscykler, mestadels av PA6-polymeren. De mekaniska egenskaperna med tillsats av återvunnet matta till en blandning av rena material visar liknande egenskaper jämfört med endast rena material. Sammanfattningsvis är det möjligt att 3D-skriva med återvunnet mattfilament för att skapa en 3D-skriven produkt, metoden verkar lovande.

The microalgae Scenedesmus Bloom are grown in sewage environment and contains, among other things, polymers of saccharides. The polysaccharides can possibly be extracted and used for the manufacturing of plastic material. The algae have a strong cell wall, can grow fast in severe external conditions and shows good ability to capture carbon dioxide. This study attempts to extract polymers from the algae, which will be used to create plastic films based on the microalgae. Analyses were made to determine which method gave the best results. The extraction methods that were performed were acid hydrothermal extraction, ultrasonic extraction and a combination of both methods. Before the extraction took place, preparation of the algae was performed. The preparation consisted of grinding the algae and washing the algae with acetone. The washing methods used in this study showed to not have a big influence and was therefore considered unnecessary. After the extraction, methods as dialysis and freezedrying were performed, for purification and drying of the extracted material. Finally, plastic films were made by a mixture of the extracted material and carboxymethylcellulose sodium salt. Successful films were created from extracted material from washed algae that had undergone ultrasonic extraction and from unwashed algae that had undergone the acid hydrothermal extraction. The study showed that washed algae that had undergone ultrasonic extraction gave the best results. The created films were very brittle and without the addition of any additives, no useful applications could be found. / Mikroalgen Scenedesmus Bloom odlas i avloppsmiljö och innehåller, bland annat, polymerer av sackarider. Polysackariderna kan eventuellt extraheras och användas för tillverkning av plastmaterial. Algerna har en stark cellvägg, kan växa i svåra yttre förhållanden och visar god förmåga på att fånga koldioxid. I denna studie görs försök att extrahera polymerer från algerna för att sedan tillverka plastfilmer baserade på mikroalgerna. Analyser gjordes för att bestämma vilken metod som gav de bästa resultaten. De extraktionsmetoder som utfördes var hydrotermisk extraktion med syra, ultraljudsextraktion och en kombination av båda metoderna. Innan extraktionsmetoderna ägde rum, utfördes förbehandling på algerna, vilket bestod av malning och tvättning med aceton. De tvättningsmetoder som användes i denna studie visade sig ha en tämligen liten effekt och ansågs därför som onödiga. Efter extraktionsmetoderna utfördes även metoder som dialys och frystorkning för rening och torkning av det extraherade materialet från algerna. Slutligen framställdes plastfilmer genom en blandning av det extraherade materialet och karboximetylcellulosa. Lyckade filmer skapades från extraherat material från tvättad alg som genomgått ultraljudsextraktion och från otvättad alg som genomgått hydrotermisk extraktion med syra. Det visade sig att tvättad alg som genomgått ultraljudsextraktionen gav bäst resultat. Plastfilmerna var mycket spröda och utan tillsatser kunde inga direkta tillämpningar ses.