This degree project was performed in collaboration with ECORUB AB. Polymeric materials like thermoplastic and rubber are produced in massive quantities all over the world. However, the percentage of items that are recycled is quite low. Instead of using virgin material as the raw material for production, in this thesis, it is mainly focused on equipping the recycled raw materials to fabricate the 3D-printable filaments to be used as a feedstock material for FDM technique. This step helps to move towards a circular economy to ensure the sustainable usage of material resources. In this thesis, the material selection was constrained to recycled PETG and recycled PP. The objective of this thesis is to identify the problems faced during the utilization of recycled raw materials for 3D-printable filament production. The identified problem was resolved by tailoring the material properties by adding recycled EPDM powder as a filler material. This thermoplastic composite has shown improvement in the material and mechanical properties. The 3D-printable filaments were fabricated using thermoplastic composite materials and the mechanical properties of the parts printed using the thermoplastic composite material were investigated according to the ISO standards. Finally, it was concluded that equipping the recycled EPDM powder as a filler material with recycled PETG, showed an improvement in the impact properties of recycled PETG. When the recycled EPDM powder was combined with the recycled PP materials it helped to improve the shrinkage and the warping issues of recycled PP. The recyclability of the recycled PETG composites was investigated. Keywords: Additive Manufacturing, FDM technique, recycled raw materials, 3D-Printable Filament production faculty of Science and Technology, Uppsala University. Place of publication

Thermally expandable microspheres are polymeric core/shell particles in which a volatile hydrocarbon is encapsulated by a thermoplastic shell. When these microspheres are heated, they expand and increase their volume dramatically. This volume increase is retained upon cooling, leading to a density reduction from around 1100 kg m-3 to about 30 kg m-3. Since the development in the early 1970´s, microspheres have been used extensively by the industry as a foaming agent or light weight filler. In this thesis, microspheres with a poly(acrylonitrile-co-methacrylonitrile) shell have been synthesized through free radical suspension polymerization. The microspheres have been characterized with respect to particle morphology and expansion properties in order to deepen the understanding of the microspheres. It was found that the monomer feed ratio and the polymerization temperature are very important parameters with respect to the expansion properties. Excellent expansion could only be accomplished when polymerizing at 62 °C, with the acrylonitrile feed, fAN, being around 60 mol%, even though core/shell microspheres are formed over a much wider range of fAN. Furthermore, no expansion was achieved when polymerizing at 80 °C, even though no noticeable differences were found, compared to the corresponding sample polymerized at 62 °C. It was also shown that the expansion properties can be modified by replacing the encapsulated hydrocarbon by another hydrocarbon with a different boiling point. Not only is the boiling point important, the structure of the hydrocarbon is also important. Isooctane which is highly branched was found to give superior expansion compared to linear or cyclic hydrocarbons having a similar boiling point. Crosslinking of the polymer shell has proven to be very important for the expansion properties. Both the amount and the structure of the crosslinker are important parameters. Especially the maximum expansion can be improved by the crosslinking of the polymer shell. This originates in an increase in the shape persistence of the expanded microspheres at elevated temperatures. By the combination of crosslinkers that are incorporated separately into the polymer shell, the onset temperature of expansion can be increased significantly. Finally, the surface of microspheres has been modified by grafting poly(glycidyl methacrylate) from the surface by ARGET ATRP. Given that the reaction conditions are appropriate, such modifications can be performed with only limited effects on the expansion properties of the microspheres.

Dendrimers are perfectly branched, well-defined macromolecules with a layered structure and a large amount of peripheral end groups. The high functionality in combination with the possibility of dendrimers to adopt a globular shape at high molecular weights, gives them very unique properties.In this work dendrimers up to fifth generation based on 2,2-bis(methylol)propionic acid (bis-MPA) were synthesized with different core structures. The core moieties were chosen in aspects of functionality and flexibility and the impact of the core on the physical and rheological properties was studied. By using the divergent growth approach dendrimers with acetonide, hydroxyl, allyl ether and methacrylate end groups were obtained.The bulk properties of the acetonide- and hydroxyl- terminated dendrimers were investigated with a rheometer. Temperature sweep tests were performed on the acetonide protected dendrimers in a temperature range of -50 up to 120°C at a constant frequency of 1 Hz. It was observed that the glass transition temperature (Tg) increased with increasing generation and that the modulus dropped without a trace of rubbery plateau for lower generations. This lack of rubbery plateau is due to the absence of entanglements between dendrimers. Interestingly, a small rubbery plateau was visible for generation five which implies enhanced interactions between the dendrimers. This behaviour suggests to be strongly influenced by the structural collapse at higher generations. Further, frequency sweep tests were performed on hydroxyl functional dendrimers at different temperatures. The results revealed Newtonian properties for lower generations and shear-thinning behaviour for higher generations at high frequency.Furthermore, this research involves the creation of well-defined thiol-ene networks by incorporation of allyl ether or methacrylate functional dendrimers in thermosets. This was accomplished by using two trithiols of different molecular weights and react them with the enes under UV irradiation. The thiol-methacrylate crosslinking reaction resulted in inhomogeneous films with and residual unsaturations. The thiol-ene films based on allyl ether dendrimers, on the contrary, resulted in homogeneous films with intermolecular couplings between the ene and the thiol being the dominant mode of polymerization. / Dendrimerer är perfekt grenade, väldefinierade molekyler med en struktur indelad i lager och med ett stort antal ändgrupper. Dendrimerer har, på grund av sina många funktionella grupper och sin förmåga att vid höga molekylvikter anta en mer sfärisk struktur, väldigt speciella egenskaper. Dendrimerer upp till femte generation, baserade på 2,2-dimetylolpropan syra (bis-MPA), har syntetiserats med olika typer av kärnstrukturer. Kärnorna valdes med avseende på funktionalitet och flexibilitet, och strukturens påverkan på dendrimerernas fysikaliska och reologiska egenskaper undersöktes. Dendrimerer med acetonid-, hydroxyl-, allyleter- samt metakrylatändgrupper syntetiserades genom att använda en divergent syntesmetod. De hydroxyl- och acetonidfunktionella dendrimerernas reologiska egenskaper i bulk karakteriserades med en reometer. De acetonidskyddade dendrimererna karakteriserades med temperatursvep i ett intervall mellan -50 °C och 120°C och med en konstant frekvens på 1 Hz. Analyserna visade att glastransitionstemperaturen (Tg) ökade med ökande generation och att dendrimerer av lägre generation inte uppvisade någon gummiplatå. Anledningen till detta är att det inte förekommer några kedjeintrasslingar mellan dendrimerer. Dock uppvisar femte generationens dendrimerer liten gummiplatå vilket pekar på ökade interaktioner mellan dem. Detta beteende påverkas av att dendrimerna kollapsar vid höga generationer och att förändringen i strukturen tydligt påverkar interaktionerna. Hydroxylfunktionella dendrimererna karaktäriserades med frekvessvep vid olika temperaturer. Det visade sig att lägre generationer uppvisar Newtonskt beteende medan högre generationer visar sig vara skjuvförtunnande vid höga frekvenser. Som en ytterligare del i detta projekt skapades väldefinierade tiol-en nätverk genom att reagera allyleter och metakrylat-funktionella dendrimerer med två trifunktionella tioler av olika molekylvikt. Reaktionerna initierades med UV-ljus. Tiol-metakrylat filmerna visade på en hög andel homopolymerisation vilket resulterade i inhomogent tvärbundna nätverk med ett stort antal oreagerade grupper. Tiol-allyleter filmerna visade uppvisade däremot homogena nätverk med en liten andel homopolymerisation. / QC 20100831

During the past few decades, laser technology has had a strong impact on our society, providing important contributions to materials processing, data storage, communications, medicine, and defense applications. However, the progress in laser technology has also brought about the development of harmful portable high‐power lasers and tactical laser weapons. As a result, the hazard of being blinded by lasers (accidentally or from hostile use) has increased significantly. Hence, the need for protection against lasers has emerged. In order to protect optical sensors against harmful laser radiation, materials that absorb high intensity light, such as nonlinear absorbing chromophores, are employed. The concept of controlling the intensity of an optical light beam is usually referred to as optical power limiting and can be used efficiently in sensor protection devices.In this thesis, various nonlinear absorbing platinum(II) acetylides have been synthesized and characterized regarding their photophysical and optical limiting properties. Dendronized platinum(II) acetylides were prepared in order to evaluate the site isolation effect offered by the dendritic surrounding. The photophysical measurements reveal that the dendritic encapsulation enhances the phosphorescence, increases the luminescence lifetimes, and improves the optical limiting performance due to reduced quenching of the excited states.Triazole‐containing chromophores were synthesized using click chemistry to achieve functionalized platinum(II) acetylides. It was found that the position of the triazole unit affects the photophysical properties of these chromophores. The most promising results were obtained for the chromophore with the triazole located at the end of the conjugation where it may act as an electron donor, thus contributing to improved two‐photon absorption.A branched platinum(II) acetylide was also prepared in order to investigate the effect of multiple conjugated arms as well as multiple heavy atoms within the same molecule on the optical limiting performance. The star shaped chromophore reached the lowest clamping level of all compounds included in this thesis and constitutes a highly suitable chromophore for optical power limiting applications.The nonlinear absorbing chromophores were also incorporated into novel solid state materials based on PMMA. The actual device fabrication of doped organic glasses as optical limiters for sensor protection is presented, and their optical limiting performance is reported. The obtained organic glasses can reduce the transmission of high intensity light by 97 %. / QC 20100920

The biotechnology industry is one of the fastest growing sectors of the western economy. The biotech industry is helping the world by creating significant societal and economic value in various sectors. However, as a result of the fast development of the biotech industry, the environment is constantly changing and doing so at a high pace. Hence, biotech companies are forced to always stay competitive and improve their business in order not to be outrivaled. XYZ is a family-owned chemical company based in Europe. The company’s main business is polysaccharide chemistry but specializes in fluorescent dextran derivatives for which XYZ offer different goods and services. Dextran is a polysaccharide that has been widely used as a research tool in various scientific fields. XYZ has been struggling with stagnating sales and wants to grow their business and find new customers. The purpose of this master thesis is to suggest ways of business development for XYZ through customer and market understanding. Assessment of the company’s current strategy, market and customers will aid in understanding the company’s value proposition and identify opportunities for business development. Data were collected mainly through qualitative unstructured interviews. In conclusion, based on the empirical results we recommend to assess the value propositions that the company is currently offering to customers. This should be done before reaching out to new customers. Further, this project aims to describe the factors a small research-based enterprise should consider when designing a business strategy. / In this paper, a synthetic method for fixable FITC-alpha-Lys-dextran is examined and evaluated. Starting dextran molecular weight average was 70 kDa. One application of dextran is to attach some fluorescent group in order to visualize biological systems. Fluorescent dextrans have been proven useful as a macromolecular tracer when studying for example permeability of blood vessels and the lymphatic system. In some biological applications, fluorescent dextrans need to be fixed. This means that you can follow parts of the cell more easily as they move around. These so- called 'fixable dextrans' are susceptible to cross-linking by aldehyde-treatment. It can then bind covalently to biomolecules. These fixed fluorescent dextrans can then be detected by ultrastructural and immunohistochemical techniques. This four step synthesis resulted in 59 % yield of FITC-alpha-Lys-dextran with a degree of substitution at 0.12 % Molecular weight average of the final product was approximately 72 kDa with a polydispersity of approximately 1.45. Emission maxima occurred at 519 nm.

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<p>Det här arbetet har utförts som ett 30 hp examensarbete för kemiingenjörsutbildning på Karlstads universitet åt Stora Enso, Forshaga. Syftet var att undersöka koronabehandlingens effekt på plastbelagda kartongytor. Frågor som hur effekten minskar under lagringstid, om effekten påverkas av materialets bredd, tjocklek, pigment i plasten samt kylvalsarnas påverkan skulle undersökas.</p><p> </p><p>Största delen i arbetet var att undersöka hur ytenergin på behandlad plastbelagd kartong minskar med tiden och om detta varierar beroende på behandlingsgraden. Resultaten visade som väntat att ytenergin sjunker med tiden och ju högre ytenergin var direkt efter behandlingen desto fortare sjunker den. Direkt efter behandlingen varierade värdena ganska mycket men efter ca en vecka så verkade ytan ha "lugnat sig" (antagligen hade antalet laddningar som fanns på ytan direkt efter behandlingen då minskat). Ytenergin sjunker snabbast under den första månaden och sedan börjar kurvan plana ut. Efter ca två månader är nivån ganska stabil. Vid jämförelse av olika bredder gick det att se små skillnader som visade att breda rullar kräver mindre effekt för att nå ett visst dyntal än vad en smalare rulle gör. Samtidigt gick det att se att rullarna tycks ha något lägre ytenergi i kanten av rullarna än vad de har i mitten, men inte heller här handlar det om några stora skillnader.</p><p> </p><p>Arbetet innefattade även ett test för jämförelse av olika ytvikter på kartongen och det visade sig att ett tjockt material kräver mer energi vid behandlingen än ett tunnare, men skillnaden är liten. Det gick även att se skillnader vid jämförelsen av rullar som belagts med pigmenterad plast och de som belagts med transparent. Polyetylen med pigment i kräver lite högre effekt vid behandlingen för att kunna nå upp till lika hög ytenergi som samma material belagd med transparent plast.</p><p> </p><p>Det sista testet som skulle visa om det finns skillnader mellan matt och blank kylvals visade att olika kylvalsar gav olika ytråhet, men skillnaden mellan valsarna blir större på en ytrå yta än på en slät yta. Det var stora skillnader mellan valsarna om de jämfördes på dekorsidan, men på mer ytråa insidan verkade inte kylvalsen ha lika stor inverkan.</p><p> </p>

Det här arbetet har utförts som ett 30 hp examensarbete för kemiingenjörsutbildning på Karlstads universitet åt Stora Enso, Forshaga. Syftet var att undersöka koronabehandlingens effekt på plastbelagda kartongytor. Frågor som hur effekten minskar under lagringstid, om effekten påverkas av materialets bredd, tjocklek, pigment i plasten samt kylvalsarnas påverkan skulle undersökas.   Största delen i arbetet var att undersöka hur ytenergin på behandlad plastbelagd kartong minskar med tiden och om detta varierar beroende på behandlingsgraden. Resultaten visade som väntat att ytenergin sjunker med tiden och ju högre ytenergin var direkt efter behandlingen desto fortare sjunker den. Direkt efter behandlingen varierade värdena ganska mycket men efter ca en vecka så verkade ytan ha "lugnat sig" (antagligen hade antalet laddningar som fanns på ytan direkt efter behandlingen då minskat). Ytenergin sjunker snabbast under den första månaden och sedan börjar kurvan plana ut. Efter ca två månader är nivån ganska stabil. Vid jämförelse av olika bredder gick det att se små skillnader som visade att breda rullar kräver mindre effekt för att nå ett visst dyntal än vad en smalare rulle gör. Samtidigt gick det att se att rullarna tycks ha något lägre ytenergi i kanten av rullarna än vad de har i mitten, men inte heller här handlar det om några stora skillnader.   Arbetet innefattade även ett test för jämförelse av olika ytvikter på kartongen och det visade sig att ett tjockt material kräver mer energi vid behandlingen än ett tunnare, men skillnaden är liten. Det gick även att se skillnader vid jämförelsen av rullar som belagts med pigmenterad plast och de som belagts med transparent. Polyetylen med pigment i kräver lite högre effekt vid behandlingen för att kunna nå upp till lika hög ytenergi som samma material belagd med transparent plast.   Det sista testet som skulle visa om det finns skillnader mellan matt och blank kylvals visade att olika kylvalsar gav olika ytråhet, men skillnaden mellan valsarna blir större på en ytrå yta än på en slät yta. Det var stora skillnader mellan valsarna om de jämfördes på dekorsidan, men på mer ytråa insidan verkade inte kylvalsen ha lika stor inverkan.

The current study and discuss the long-term properties of biomedical polymers in vitro and invivo and presents means to design and manufacture antimicrobial composites. Antimicrobialcomposites with reduced tendency for biofilm formation should lead to lower risk for medicaldevice associated infection.The first part analyse in vivo degradation of invasive silicone rubber tracheostomy tubes andpresents degradation mechanism, degradation products and the estimated lifetime of thematerials.. It was found that silicone tubes undergo hydrolysis during the long-term exposurein vivo, which in turn results in decreased stability of the polymer due to surface alterationsand the formation of low molecular weight compounds.The second part of the study presents the manufacturing of composites with single, binary andternary ion-exchanged zeolites as an antimicrobial agent. The ion distribution and release ofthe zeolites and the antimicrobial efficiency of the different systems showed that single silverion-exchanged zeolite was superior to the other samples. Antimicrobial composites wereprepared by mixing the above-mentioned zeolites and pure zeolite (without any ion) withdifferent fractions into polyether (TPU), polyether (PEU) polyurethane and silicone rubber.The antimicrobial efficiency of binary and ternary ion-exchanged samples was similar whichis thought to be due to the ion distribution in the crystal structure.The changes in the mechanical and surface properties of the composites due to the zeolitecontent demonstrated that the increasing zeolite content reduced the mechanical propertieswhile the surface properties did not change significantly. The antimicrobial tests showed thatthe silver-containing composite was the most efficient among all the other samples. Thebinary and ternary ion-exchanged composites expressed similar antimicrobial efficiency as itwas seen previously for the different zeolite systems. Biocompatibility was studied byexposure to artificial body fluids to simulate the degradation of the composites in the humanbody. Significant changes were observed in the morphology, the surface properties and the chemical structure. / QC 20110511