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Wet spinning of carbon fiber precursors from cellulose-lignin blends in a cold NaOH(aq) solvent systemAlice, Landmér January 2022 (has links)
Carbon fiber (CF) is predominantly produced from fossil-based sources and is therefore an area of interest for further development towards a more sustainable society. The purpose of this thesis work was to investigate the possibility of producing precursor fibers (PFs) for CF production from a blend of renewable cellulose andlignin. Cellulose, which is used to some extent for CF production, was chosen, while the possibility of adding lignin was investigated in hope of increasing the gravimetric yield of the CF production. Blends of softwood kraft cellulose pulp (SKP) and softwood kraft lignin (SKL) were dissolved in an alkaline (NaOH) solvent system at different cellulose/lignin ratios. A total of eight dopes were prepared (SKP/SKL ratios of 100/0–60/40 wt./wt.) with total dope concentrations ranging from 4.5 wt.% to 9.2 wt.%. The addition of SKL resulted in dark colored dopes with viscosities of which mainly appeared to depend on the SKP concentration. The dopes were wet spun, resulting in continuously spun PFs. The PFs showed on an increasing pyrolysis yield with increased SKL content but decreasing mechanical properties. However, process optimization was not included in the work, subsequently leading to the assumption that greater values on mechanical properties can be achieved. A pure SKP PF and a SKP-SKL (70/30 wt./wt.) PF were successfully thermally converted into CFs by carbonization at 1000 °C. The PF containing SKL had a total gravimetric yield more than twice as high as the pure SKP PF, 28 wt.% and 12 wt.%, respectively. Thereby, the addition of SKL seems to have a positive impact on the CF yield when utilizing a NaOH(aq) solvent system. This thesis work has become a base for the future work towards the development of CFs from wet spun cellulose-lignin PFs in the NaOH(aq) solvent system.
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Injectable and shape-retaining collagen hydrogel, crosslinked using bio-orthogonal cycloaddition chemistry / Injicerbara och formbevarande kollagenhydrogeler, tvärbundna med bio-ortagonal cykloadditionskemiSharq, Murtaza January 2022 (has links)
Under senaste decennierna, har intresset kring implantat från naturliga och syntetiska polymerer ökat markant i samband med en ökad marknadsefterfrågan på vävnadsdonationer. Detta har lett till efterforskningen av nya in-situ formerande geler med formbevarande egenskaper in-vivo. Extracellulära matrisen (ECM) innehåller flertal makromolekylära komponenter med stödjande och nätverksformerande egenskaper, då de ofta är essentiella strukturella konstituenter i biologiska system. Den huvudsakliga beståndsdelen i ECM-nätverket, kollagen typ-1, har undersökts som en kandidat för utvecklingen av nya modifierade biomaterial med cellförökande-, biokompatibla-, icke-svällande samt injicerbara egenskaper. I detta projekt var grisderiverat kollagen modifierat med furfuryl glycidyl eter, och tvärbundet med 10 kDa 8-armad PEG-malimid, vilket genomgick kovalenta Diels-alder klick-reaktioner. Fyra formuleringar användes i experimenten, baserat på de stökiometriska förhållandet mellan furan och malimid i det kemiskt modifierade kollagenet. Dessa kollagen-baserade hydrogeler undersöktes baserat på 4 wt% löst kollagen, med avseende på reologiska-, mekaniska-, bionedbrytbara och svällningsegenskaper. Resultaten indikerar att en ökning i fastfas-mängd ledde till en förhöjning i hydrogelens styvhet. Detta kunde observeras genom en ökad lagringsmodul (G’) under reologiska mätningar. Samtidigt indikerade mätningarna att sprödheten av hydrogelen ökade i korrelation med ökningen av styvheten. Vidare drogs slutsatsen att kovalenta interaktionerna är enbart delvis ansvarig för ökningen av G’. Jämförelser med tan delta och kritiska töjningen visade att det fanns fysiska interaktioner mellan polymererna vilket också bidrog till ökningen av G’ för gelformuleringar som innehöll furan-till-malimid förhållanden på 1:1 och 1:4. Dessa fysiska interaktioner tros härstamma från en ökning av hydrofobiska effekter mellan kollagen kedjorna, då agglomerering och löslighetssvårigheter i vattenlösningar observerades i flertal experiment. Kollagen-PEG-Malimid hydrogelen var också injicerbar genom 15G kanyler, nedbrytbar in-vitro i närvaro av kollagenas, och uppvisade låg svällning i vatten. Inga cellexperiment genomfördes, och därav kunde inga slutsatser dras i hydrogelens cellförökande egenskaper. Däremot har tidigare arbete av Dr Jamadi visat att kollagen-PEG-malimid hydrogel med 2 vikt% haft kapacitet att inkapsla celler. Detta kan vara en indikation att högre viktprocent av gelen också kan uppvisa samma effekt vid framtida försök.Sammanfattningsvis, kunde slutsatsen dras att hydrogelen uppvisar flertal av de spekulerade, samt några av de eftertraktade egenskaperna hos en injicerbar hydrogel som potentiellt kan användas kliniskt. / In recent decades, the interest in implants manufactured from natural and synthetic polymers has grown as the demand for tissue donations has increased. This process has led to the pursuit of new, in-situ forming gels with shape-retaining properties in-vivo. The extracellular matrix (ECM) contains several macromolecular constituents with scaffold forming capabilities and is an inherent part of the body. The main component in the ECM-scaffold, collagen type-I, has been investigated as a candidate for novel modified biomaterials with cell proliferating, biocompatible, non-swelling, and injectable properties. Collagen was modified with furfuryl glycidyl ether and crosslinked with 10 kDa 8-arm PEG-maleimide, which undergoes Diels-alder covalent click-type reactions. Four formulations were used, based on a stoichiometric ratio of furan to maleimide (1:1-1:4). These materials' properties were evaluated at 4 wt% collagen for rheological-, mechanical-, biodegradability and swelling characteristics. The results indicated that an increase in solid content improved stiffness in the hydrogel. This was observed by an increase of storage modulus (G’) during rheological measurements. The same measurements also indicated that the hydrogel showed an increase in brittle characteristics correlated with higher solid content. Furthermore, it was concluded that the covalent interactions are partly responsible for the increase of G’. Comparisons in tan delta and critical strain showed that there are physical interactions that cause the increase in moduli for gel formulations containing furan to maleimide ratios of 1:1 and 1:4. These physical interactions are thought to stem from the increase in hydrophobic effects of the modified collagen, as agglomeration and solubility issues in aqueous solutions are observed in multiple experiments. Collagen-PEG-maleimide hydrogel was also injectable through a 15-gauge needle, degradable in-vitro, and showed low swelling. No cell experiments were performed, and hence no conclusions could be made of this aspect of the hydrogel. However, work has been performed by Dr Jamadi, which indicates that the Collagen-PEG-Maleimide hydrogel with lower weight percentages allows for cell encapsulation. Hence, it could be concluded that several characteristics of tissue mimetic material were met with this hydrogel.
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Modelling the degradation processes in high-impact polystyrene during the first use and subsequent recyclingVilaplana, Francisco January 2007 (has links)
Polymers are subjected to physical and chemical changes during their processing, service life, and further recovery, and they may also interact with impurities that can alter their composition. These changes substantially modify the stabilisation mechanisms and mechanical properties of recycled polymers. Detailed knowledge about how the different stages of their life cycle affect the degree of degradation of polymeric materials is important when discussing their further waste recovery possibilities and the performance of recycled plastics. A dual-pronged experimental approach employing multiple processing and thermo-oxidation has been proposed to model the life cycle of recycled high-impact polystyrene (HIPS). Both reprocessing and thermo-oxidative degradation are responsible for coexistent physical and chemical effects (chain scission, crosslinking, apparition of oxidative moieties, polymeric chain rearrangements, and physical ageing) on the microstructure and morphology of polybutadiene (PB) and polystyrene (PS) phases; these effects ultimately influence the long-term stability, and the rheological and mechanical behaviour of HIPS. The PB phase has proved to be the initiation point of HIPS degradation throughout the life cycle. Thermo-oxidation seems to have more severe effects on HIPS properties; therefore, it can be concluded that previous service life may be the part of the life cycle with the greatest influence on the recycling possibilities and performance of HIPS recyclates in second-market applications. The results from the life cycle degradation simulation were compared with those obtained from real samples from a large-scale mechanical recycling plant. A combination of different analytical strategies (thermal analysis, vibrational spectroscopy, and chromatographic analysis) is necessary to obtain a detailed understanding of the quality of recycled HIPS as defined by three key properties: degree of mixing, degree of degradation, and presence of low molecular weight compounds. / QC 20101119
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Producing the biobased films of tomorrow : Nanocellulose dewatering with non-confined mechanical pressingRoos, John Eric January 2024 (has links)
Cellulose Nano Fibrils (CNFs) can be extracted from wood and other plants. These CNFs are expected to play a large roll in future materials owing to their interesting properties and biobased nature. In this project, dewatering of gels made from CNF by non-confined mechanical pressing has been studied. A CNF suspension was gelled by the addition of HCl at pH 2 to form gel cakes and then pressed mechanically. The goal was to find the pressure limits of the gel cakes for different starting concentrations, in weight percentage [wt%], of CNF to optimize the pressure used when dewatering CNF gels. The non-confined pressing was achieved via the useof a Zwick/Roell Torsion multi-axis testing system. Gel cakes were pressed until a pressing equilibrium was reached. Equilibrium was reached when compression was less than 0.01 mm per 100 seconds. Gel cakes were frozen with liquid N2, freeze-dried, and analysed with Scanning Electron Microscopy (SEM). The results observed from the pressing data showed that gel cakes with higher CNF starting concentrations could survive higher pressures. Using the highest pressure available, at the pressure limit, yielded both the shortest run time and the highest dryness content. SEM imaging showed that the compression of the gel cakes starts at the surfaces and continuous inwards through the bulk. The mechanical pressure creates sheets of CNF both vertically and horizontally. By plotting the starting concentrations vs applied pressure a limit map with pressure regions could be created. From the limit map further optimization can be achieved to shorten the dewatering process of the CNF gels.
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The influence of inorganic particles on debonding efficiency of fluff pulp / Effekten av oorganiska partiklar på defibreringsenergi hos fluffmassaLindbäck, Vera January 2024 (has links)
Fluffmassa är, i ordets rätta bemärkelse, ett fluffigt material som i de allra flesta fall tillverkas av fibrer ifrån trä, den utgör en viktig del i blöjor, hygienprodukter, näsdukar och ett flertal andra produkter. Syftet med fluffmassa i absorptionsprodukter är framförallt att sprida vätskan, öka absorbtionshastigheten och behålla superabsorberande polymerer på plats i nätverket. Två viktiga kvalitetsparametrar hos fluffmassan är defibreringsenergi och knuthalt. Dessa är korrelerade till hur enkelt fibrerna kan separeras ifrån varandra i torr eller fuktad luft. Denna separation av fibrer är ett högst avgörande steg för att skapa den fluffiga massan ifrån torkade massaark. Målet med arbetet har varit att reducera defibreringsenergin och knuthalten genom att behandla massa med oorganiska partiklar genom att använda den sk. lager-på-lager (LbL) – metoden där en konsekutiv behandling av fibrerna med motsatt laddade polyelektrolyter och nanopartilkar. Genom att belägga fiberytan med tunna skikt av ett oorganiskt material var avsikten att reducera fiber-fiber-interaktionerna för att slutligen minska defiberingsenergin och knuthalten. Studien visade att en viss effekt kunde uppnås med LbL-skikt av pDADMAC (diallyldimetylammonium klorid) och MMT (montmorillonit) vilket noterades som en minskning av knuthalten från 35% till ungefär 20%, medan defibreringsenergin däremot var oförändrad jämfört med ett obehandlat referensprov. De bildade lagren visade sig vara tunnare och jämnare än förväntat vilket sannolikt ledde till en relativt liten minskning av kontaktyta och molekylär adhesion mellan fibrerna vilket kan förklara den relativt sett låga effekten av tillsatserna. De tunna lagren kan också vara en förklaring till varför ingen nämnvärd skillnad detekteras för olika antal av bildade bilager. Eftersom enbart maximalt 3 bilager studerades kan det vara rimligt att anta att en ytterligare adsorption av bilager kan leda till en ytterligare minskning av knuthalten och defibreringsenergin. Eftersom MMT-partiklarna inte var direkt synliga i SEM-analyserna är det svårt att säga exakt hur de är fördelade på fiberytan. Antingen är de jämnt fördelade eller så har vissa områden på fiberytan inte blivit täckta av MMT. Resultaten indikerar också att det finns många intressanta sätt att förbättra lagren för att nå lägre defibrerinsergier och knuthalter. Genom att tex. adsorbera större partiklar istället för tunna MMT-partiklar skulle det vara möjligt att skapa en högre ytråhet och därmed en minskad kontaktyta mellan fibrerna vilket i sin tur skulle kunna minska knuthalten och defibreringsenergin. / Fluff pulp is indeed a fluffy material, it is most commonly composed of pulp fibers from wood and it serves as a vital constituent in diapers, feminine hygiene products, napkins and a variety of other products. The purpose of fluff pulp in absorbent products is mainly to distribute fluids, increase absorption speed and hold superabsorbent polymers within the network. Two important quality parameters of fluff pulp are the defibration energy and the knot content, which are related to the ease at which the fibers can be separated from each other under dry to moist conditions. This separation of fibers is an essential step in generating the fluffy material from sheets. This project aims to reduce the defibration energy and the knot content by treating fibers with inorganic particles according to the Layer-by-Layer (LBL) technique. The main assumption was that by applying coatings to the fibers, the inter-fiber interactions can be reduced leading to a lowered defibration energy and knot content. The study showed that some effect was accomplished using layers of pDADMAC (diallydimethylammoinium chloride) and MMT (montmorillonite clay), the knot content was reduced from 35% to around 20%, but the defibration energy was unchanged compared to the untreated reference sample. The formed LBL layers appeared to be thinner and smoother than anticipated which likely lead to only a slight decrease in contact area between the fibers, hence, the reduction of knot content was detectable but not very large. Since the formed LBL layers were so thin it was difficult to find any distinguishable difference for the different numbers of bilayers, however, the maximum number of bilayers produced was only three and additional layers could lead to an amplified effect. Since the MMT particles could not be clearly visualized from the SEM instruments, it is difficult to conclude exactly how the clay platelets were distributed on the fibers. Either the MMT was distributed rather evenly across the surface of the fibers, or some areas of the fibers were left free from LbLs. The results from the present investigation show that there are many interesting ways to further improve the layers to reach lower defibration energies and knot contents. As an example the adsorption of larger particles instead of thin MMT platelets could be used allowing for a minimization of the contact area between the fibers due to an increased surface roughness of to the fiber surfaces.
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Polymer Nanocomposites in Thin Film ApplicationsFogelström, Linda January 2010 (has links)
The introduction of a nanoscopic reinforcing phase to a polymer matrix offers great possibilities of obtaining improved properties, enabling applications outside the boundaries of traditional composites. The majority of the work in this thesis has been devoted to polymer/clay nanocomposites in coating applications, using the hydroxyl-functional hyperbranched polyester Boltorn® as matrix and montmorillonite clay as nanofiller. Nanocomposites with a high degree of exfoliation were readily prepared using the straightforward solution-intercalation method with water as solvent. Hard and scratch-resistant coatings with preserved flexibility and transparency were obtained, and acrylate functionalization of Boltorn® rendered a UV-curable system with similar property improvements. In order to elucidate the effect of the dendritic architecture on the exfoliation process, a comparative study on the hyperbranched polyester Boltorn® and a linear analogue of this polymer was performed. X-ray diffraction and transmission electron microscopy confirmed the superior efficiency of the hyperbranched polymer in the preparation of this type of nanocomposites. Additionally, an objective of this thesis was to investigate how cellulose nanofibers can be utilized in high performance polymer nanocomposites. A reactive cellulose “nanopaper” template was combined with a hydrophilic hyperbranched thermoset matrix, resulting in a unique nanocomposite with significantly enhanced properties. Moreover, in order to fully utilize the great potential of cellulose nanofibers as reinforcement in hydrophobic polymer matrices, the hydrophilic surface of cellulose needs to be modified in order to improve the compatibility. For this, a grafting-from approach was explored, using ring-opening polymerization of ε-caprolactone (CL) from microfibrillated cellulose (MFC), resulting in PCL-modified MFC. It was found that the hydrophobicity of the cellulose surfaces increased with longer graft lengths, and that polymer grafting rendered a smoother surface morphology. Subsequently, PCL-grafted MFC film/PCL film bilayer laminates were prepared in order to investigate the interfacial adhesion. Peel tests demonstrated a gradual increase in the interfacial adhesion with increasing graft lengths. / QC20100621
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Novel Possibilities for Advanced Molecular Structure Design for Polymers and NetworksFinne, Anna January 2003 (has links)
Synthetic and degradable polymers are an attractive choicein many areas, since it is possible to control the way in whichthey are manufactured; more specifically, pathways tomanipulate the architecture, the mechanical properties and thedegradation times have been identified. In this work,L-lactide, 1,5-dioxepan-2-one and ε-caprolactone were usedas monomers to synthesize polymers with different architecturesby ring-opening polymerization. By using novel initiators,triblock copolymers, functionalized linear macromonomers andstar-shaped aliphatic polyesters with well-defined structureshave been synthesized. To synthesize triblock copolymers,cyclic germanium initiators were studied. The polymerizationproceeded in a controlled manner although the reaction rateswere low. To introduce functionality into the polymer backbone,functionalized cyclic tin alkoxides were prepared and used asinitiators. During the insertion-coordination polymerization,the initiator fragment consisting mainly of a double bond wasincorporated into the polymer backbone. The double bond wasalso successfully epoxidized and this gave unique possibilitiesof synthesizing graft polymers with precise spacing. Themacromonomer technique is a very effective method for producingwell-defined graft polymers. Spirocyclic tin initiators weresynthesized and used to construct star-shaped polymers. Thestar-shaped polymers were subsequently crosslinked in apolycondensation reaction. These crosslinked structures swelledin water, and swelling tests showed that by changing thestructure of the hydrogel network, the degree of swelling canbe altered. A first evaluation of the surface characteristicsof the linear triblock copolymers was also performed. AFManalysis of the heat-treated surfaces revealed nanometer-scalefibers and tests showed that keratinocytes were able to growand proliferate on these surfaces. / QC 20100602
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Dendrimers and dendronized polymers : synthesis and characterizationNyström, Andreas January 2006 (has links)
The goal of this work was to synthesize complex macromolecular architectures such as dendrimers and dendronized polymers, and evaluate the effect from the dendrons on the optical and material properties. The work presented in this doctoral thesis, Dendrimers and Dendronized Polymers - Synthesis and Characterization, is divided into one minor and one major part. The first part deals with the synthesis and characterization of two sets of dendritic porphyrins based on 2,2-bis(methylol)propionic acid (bis-MPA). The second part deals with the synthesis and characterization of dendronized poly(hydroxyl ethyl methacylate), dendronized poly(norbornene), and dendronized triblock copolymers, were the pendant dendrons are based on bis-MPA. Both free-base and zinc containing dendritic porphyrins was synthesized up to the fifth generation by employing iterative ester coupling utilizing the acetonide protected anhydride of bis-MPA as generic building block. First and second generation dendron bearing methacrylates based on 2-hydroxyethyl methacrylate were also synthesized by utilizing the acetonide protected anhydride of bis-MPA, and subsequently polymerized by atom transfer radical polymerization. By adopting a divergent “graft-to” approach starting from the first generation dendronized poly(hydroxyl ethyl methacrylate), well-defined dendronized polymers with acetonide, hydroxyl, acetate and hexadecyl surface functionality were obtained. By utilizing the same divergent iterative esterfication, first to fourth generation dendron functionalized norbornenes were synthesized. These monomers were polymerized by ring-opening metathesis polymerization, utilizing either Grubbs´ first or second generation catalyst. Acrylate functional first to fourth generation monomers were synthesized by the copper(I) catalyzed “click” coupling of azido functional dendrons and propargyl acrylate. The monomers were polymerized to dendronized triblock copolymers by reversible addition-fragmentation chain transfer polymerization, utilizing a difunctional poly(methyl methacrylate) as macro chain transfer agent. The bulk properties of the dendronized poly(hydroxyl ethyl methacrylate) and poly(norbornene) were investigated by dynamic rheological measurements and differential scanning calorimetry. It was found that all the acetonide functional bis-MPA based dendronized polymers had glass transitions temperatures in a similar range. The rheological behaviour showed that for the dendronized polymers having the same backbone length the complex viscosity as a function of functionality was independent of the surface functionality of the polymer. The generation number of the polymer had a profound influence on the complex viscosity, changing form a Newtonian behaviour to a shear thinning behaviour when the generation of the dendrons was increased from two to four. The dendronized poly(norbornene) had increasingly shorter backbone lengths for each generational increase, and for the materials set with comparably lower degree of polymerization, the G’ part of the complex modulus was mostly affected by attaching larger dendrons. In the case of the sample set of higher degree of polymerization, the second, third, and fourth generation samples had similar slopes of the G’ and G” curves, indicating a similar relaxation behaviour. / QC 20100914
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Spruce bark biorefinery / Bioraffenaderi för granbarkAhlström, Leon, Mattsson, Rebecca, Eurén, Hampus, Lidén, Alicia January 2021 (has links)
Spruce Bark contains several fundamental main substances; lignin, non-cellulose polysaccharides, cellulose and extractives. This undergraduate study focuses on developing a process to extract each of these components from spruce bark using a biorefinery concept, with a main focus on extracting lignin without degradation. The purpose of the Bark biorefinery concept is to contribute to a circular bioeconomy, by making use of natural resources. With extended research on the area, it will be possible to produce polymers, green chemicals and biofuel from the components in bark. This report covers the extraction of the bark components with soxhlet extraction, Hot-water extraction, organosolv extraction and peracetic acid delignification. The extraction was made on two samples, matchstick-sized bark (MS) and 20 mesh-sized bark with a diameter of 0.8 mm (20M). The purpose was to be able to compare the efficiency of the extraction between the two samples. Afterwards, the characterisation of extracts and residue was executed with carbohydrate analysis, 2D HSQC-NMR and FTIR-analysis. The results showed that a smaller particle size led to more efficient extractions of all components as well as more pure extract solutions. Lignin concentration determinations of samples at each step showed that a significant amount of lignin was lost prior to the organosolv extraction. Future research should look into ways to reduce this loss in order to increase the lignin yield. The findings in the FTIR and NMR analyses correlates with what could be seen in other reports, discussing similar subjects. For upscaling of this process, future research should go toward optimization of all extraction methods in order to make an upscaling of the process economically viable.
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Structural Battery Electrolytes / Strukturella Batteri-ElektrolyterÖberg, Pernilla, Halvarsson, Amanda, Rune, Julia, Bjerkensjö, Max January 2021 (has links)
Strukturella batterier är multifunktionella; de tillhandahåller lagring av elektrokemisk energi samtidigt som de bidrar med en lastbärande funktion. Tillsammans möjliggör detta att batteriet kan integreras i karossen hos ett elektriskt fordon eller apparat. Denna multifunktionalitet möjliggör således en avsevärd reducering i fordonets vikt. Kompositmaterialet är förstärkt av kolfiberelektroder, innesluten i en elektrolytstruktur. För att förverkliga detta koncept måste batteriets elektrolyt kunna motstå mekanisk belastning, samtidigt som den transporterar joner mellan batteriets elektroder. Denna studie syftar till att bygga vidare på konceptet av fas-separerade polymerelektrolyter, skapade från polymerisationsinducerad fasseparation via termisk härdning, vilket är en teknik utvecklad av Schneider et al. och Ihrner et al. Vidare undersöks effekten av att dels använda en elektrolytlösning baserad på EC:PC, men även att inkorporera tioler till polymernätverket. Tvärbindningsmolekylerna som användes i denna studie inkluderade trimetylolpropan tris(3-merkaptopropionat) (3TMP), pentaerythritol tetrakis(3-merkaptopropionat) (4PER), och dipentaerythritol hexakis-(3-merkaptopropionat) (6DPER). Dessa skiljer sig i antal funktionella tiolgrupper. Konduktivitet, termo-mekanisk prestanda och strukturberoende egenskaper undersöktes genom tre laborativa faser. Den första fasen behandlade inverkan på elektrolytsystemet av ändrat lösningsmedel, tiol-funktionalitet samt tiolgruppförhållandet gentemot allyl gruppen på den primära monomeren. Sampolymeren innehållandes 6DPER uppvisade bäst multifunktionalitet, varpå denna utvecklades vidare i fas två där en optimal sammansättning fastställdes som bestod utav 45 viktprocent jonlösning. I den slutliga fasen konstruerades en halv-cell baserat på den tidigare optimerade elektrolytkompositionen; den uppmätta kapaciteten visar tydlig förbättring jämfört med tidigare forskning. Resultatet som erhölls i denna studie bidrar till förståendet av strukturella batteri-elektrolyter samt den forskning som en dag kan komma att förverkliga strukturella batterier och dess tillämpningskrav. / Structural batteries are multifunctional; providing electrochemical energy storage synergistically with a load-bearing function that enables their integration into the body panels of electric devices and vehicles. Thus, massless energy can be achieved. As a composite material, it is composed of reinforcing carbon fibre electrodes embedded in an electrolyte matrix. To realize this concept, the electrolyte must simultaneously transfer mechanical load and transport ions between electrodes. The following study builds on a phase-separated polymer electrolyte, created using polymerization-induced phase separation via thermal curing, formulated by Schneider et al. and Ihrner et al.. The impact of the incorporation of thiols for copolymerization and as cross-linking agents for the polymer network was researched along with use of an EC:PC-based solvent. The three thiols studied were: trimethylolpropane tris(3-mercaptopropionate) (3TMP), pentaerythritol tetrakis(3-mercaptopropionate) (4PER), and dipentaerythritol hexakis-(3-mercaptopropionate) (6DPER). These differed in regard to the amount of thiol functional groups present. Ionic conductivity, thermo-mechanical performance and structure-property relationships were studied across 3 laboratory phases. The first phase concerned the effect of thiol-functionality, the thiol functional group ratio relative to the allyl group present in the primary monomer, and the solvent interaction. 6DPER was concluded to be the most promising cross-linking agent. During the second phase, the effect of electrolyte content was evaluated with an optimum of 45 weight% determined. The third phase concluded the study, wherein a half-cell was assembled with the optimized electrolyte formulation showing improved capacity relative to previous studies. The results developed here contribute to the understanding of structural battery electrolyte systems and their continued research to meet application demands.
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