<p>The development of new materials has been inspired by lessons learned from natural systems. In the area of underwater adhesion and adhesives, inspiration has come from the complex protein adhesives generated by marine organism such as barnacle and mussels. These protein systems have a high incorporation of a unique amino acid, dihydroxyphenylalanine, and provides the unique adhesive qualities synthetic systems strive to emulate.</p> <p>By understanding how marine mussels stick to a variety of surfaces, new strategies can be explored for preventing the adhesion of biological organisms to various substrates. A continuous concern for marine vessels is the detrimental impact caused by biofouling on the hull of the ship. Fuel consumption can increase as the vessel’s drag increasing fuel consumption and non-native species can be introduced into new environments. Taking inspiration from catechol curing, new oxidative surfaces were investigated as potential antifouling coatings.</p> <p>Further insight into the marine mussels ability to apply and cure its adhesive on a variety of substrate has also inspired various synthetic polymers. The catechol moiety can be incorporated into a polymer backbone to give a new solvent based adhesive. Further investigation of the poly(styrene-co-(3,4-dihydroxystyrene)) adhesive system was done to formulate an underwater adhesive for unique use cases. A terpolymer was also explored as an ideal adhesive taking inspiration from the mussels by incorporating flexible, stiff, and sticky components to give a tunable adhesive.</p> <p>Having a strong bonding synthetic adhesive that can be used on a laboratory scale is good for academic investigation, but not of use outside the lab if it cannot easily be produced on a commercial scale. With the goal of large scale synthesis, a new polymerization method was introduced addressing some of the issues currently preventing commercial scale production.</p><br>

<div>Surface level molecules act as an interface that mediates between the surface and the environment. In this way, interfacial molecules are responsible for conferring characteristics of relevance to many modern material science problems, such as electrical conductivity and wettability. For many applications, such as organic photovoltaics and nanoelectronics, macroscopic placement of chemical patterns at the sub-10 nm must be achieved to advance next generation device applications.</div><div><br></div><div>In the work presented here, we show that sub-10 nm orthogonal features can be prepared by translating the building principles of the lipid bilayer into striped phase lipids on 2D materials (e.g. highly ordered pyrolytic graphite (HOPG), MoS2). Macroscopic patterning of these nanoscopic elements is achieved via Langmuir Schafer deposition of polymerizable diyne amphiphiles. On the Langmuir trough, amphiphiles at the air water interface are ordered into features that can be observed on the macroscale using Brewster angle microscopy. Upon contact of the 2D material with the air-water interface the macroscopic pattern on the trough is transferred to the 2D material creating a macroscopic pattern consisting of sub-10 nm orthogonal chemistries. We also show here how hierarchical ordering can be accomplished via noncovalent microcontact printing of amphiphiles onto 2D materials. Microcontact printing allows a greater measure of control over the placement and clustering of interfacial molecules.</div><div><br></div><div>The alkyl chain/surface enthalpy has a great deal of influence over the ordering of amphiphiles at the sub-nm scale. Here, we examine this influence by depositing diyne amphiphiles onto MoS2 which has a weaker alkyl adsorption enthalpy compared to HOPG. We found that dual-chain amphiphiles deposited on MoS2 adopt a geometry that maximized the molecule-molecule interaction compared to the geometry adopted on HOPG.</div><div><br></div><div>Finally, we show how the hierarchical pattern of diyne amphiphiles can be transferred off of the 2D material onto an amorphous material. This is done by reacting the amorphous material with the conjugated backbone of the diyne moiety through a hydrosilylation reaction to exfoliate the film from the 2D crystalline material. The resulting polymer ‘skin’ has many applications were controlling interfacial properties of an amorphous material is important.</div>

This thesis deals with the engineering of novel nanomaterials, particularly nanocomposites and nanostructured surfaces with enhanced functionalities. The study includes two parts; in the first part, an in situ sol-gel polymerization approach is used for the synthesis of polymer-inorganic hybrid material and its exceptional transparent UV-shielding effect has been investigated. In the second part, electrodeposition process has been adapted to engineer surfaces and the boiling performance of the fabricated nanostructured surfaces is evaluated. In the first part of the work, polymer-inorganic hybrid materials composed of poly(methylmethacrylate) (PMMA) and zinc compounds were prepared by in situ sol-gel transition polymerization of zinc complex in PMMA matrix. The immiscibility of heterophase of solid organic and inorganic constituents was significantly resolved by an in situ sol-gel transition polymerization of ZnO nanofillers within PMMA in the presence of dual functional agent, monoethanolamine, which provided strong secondary interfacial interactions for both complexing and crosslinking of constituents. In the second part of the work, nanoengineering on the surface of copper plates has been performed in order to enhance the boiling heat transfer coefficient. Micro-porous surfaces with dendritic network of copper nanoparticles have been obtained by electrodeposition with dynamic templates. To further alter the grain size of the dendritic branches, the nanostructured surfaces underwent a high temperature annealing treatment. Comprehensive characterization methods of the polymer-inorganic hybrid materials and nanoengineered surfaces have been undertaken. XRD, 1H NMR, FT-IR, TGA, DSC, UV-Vis, ED, SEM, TEM and HRTEM have been used for basic physical properties. Pool boiling tests were performed to evaluate the boiling performance of the electrodeposited nanostructured micro-porous structures. The homogeneous PZHM exhibited enhanced UV-shielding effects in the entire UV range even at very low ZnO content of 0.02 wt%. Moreover, the relationship between band gap and particle size of incorporated ZnO by sol-gel process was in good agreement with the results calculated from the effective mass model between bandgap and particle size. The fabricated enhanced surface has shown an excellent performance in nucleate boiling. At heat flux of 1 W/cm2, the heat transfer coefficient is enhanced over 15 times compared to a plain reference surface. A model has been presented to explain the enhancement based on the structure characteristics. / QC 20101118

The work presented in this thesis was conducted at Uppsala University and at Swerim AB. The study aims to broaden the knowledge about the corrosion of additively manufactured bioresorbable alloy WE43 in humanlike conditions for future applications. Biodegradable metal implants are implants meant to stay in the body and support the wounded bone for a certain time period, and then degrade as new, healthy bone forms in its place. Magnesium alloys have properties that are desired for these kind of implants as it is biodegradable, non-toxic and matches the mechanical properties of bone. Furthermore, magnesium alloy WE43, containing yttrium, neodymium and zirconium, already exist on the market as a powder extruded screw that treats Hallux valgus, thus proves the alloys compatibility as a bioresorbable implant. However, in order to optimize implants for specific situations, additive manufacturing can be a powerful tool. By utilizing the advantages of additive manufacturing, patient specific, complex designs implant can be manufactured rapidly in order to be used in a patient. On the other hand, additive manufacturing is a complex method with many aspects affecting the outcome. Therefore it is important to study the influence that different parameters have on the material's properties, especially the corrosion properties. This thesis aims to study different power settings on the laser in the manufacturing process and what effect it has on the microstructure as well as the corrosion properties of as built WE43 samples. Samples of three different parameters settings were manufactured with a Powder Bed Fusion-Laser Beam 3Dprinter. These samples were analyzed regarding surface roughness and microstructure with Light Optical Microscope, Scanning Electron Microscope, Energy Dispersive Spectroscopy, Electron Backscatter Diffraction and Alicona InfiniteFocus. Furthermore, the corrosion properties of the samples were investigated by collecting and measuring hydrogen gas that is released during the corrosion process. In addition, the electrolyte were examined regarding the change in ion concentration and electrochemical tests were performed. It was found that the samples did not differ substantially in microstructure as all three parameter settings exhibited a matrix of magnesium and precipitates of alloying elements. However, the sample manufactured at the lowest energy density had pores incorporated in the bulk. Despite the porous bulk this sample performed best in the immersion tests and exhibited the lowest corrosion rate over 28 days. The reason for this behavior is not determined, however possible causes are discussed and further studies are recommended.

The performance and lifetime of lithium-ion batteries are strongly influenced by their composition. One category of critical components are electrolyte additives, which are included primarily to stabilize electrode/electrolyte interfaces in the battery cells by forming passivation layers. The presented study aimed to identify and study such an additive that could form a hydrogen-evolution-suppressing solid electrolyte interphase (SEI) in lithium-ion batteries based on aqueous electrolytes. A promising molecular additive, ethyl 2,2-difluoroacetate (EDFA), was found to hold the qualities required for an SEI former and was herein further analyzed electrochemically. Analysis of the battery cells were performed with linear sweep voltammetry and cyclic voltammetry with varying scan rate and EDFA concentrations. Results show that both 1 and 10 w-% EDFA in the electrolyte produced hydrogen-evolution-suppressing SEI:s, although the higher concentration provided no apparent benefit. Lithium-ion full-cells based on LiMn2O4 vs. Li4Ti5O12 active materials displayed poor, though partly reversible, dis-/charge cycling despite the operation of the electrode far outside the electrochemical stability window of the electrolyte. Inclusion of reference electrodes in the lithium-ion cells proved to be immensely challenging with unpredictable drifts in their electrode potentials during operation. To summarize, HER-suppressing electrolyte additives are demonstrated to be a promising approach to stabilize high-voltage operation of aqueous lithium-ion cells although further studies are necessary before any practical application thereof can be realized. Electrochemical evaluation of the reaction mechanism and efficiency of the electrolyte additives relies however heavily on the use of reference electrodes and further development thereof is necessary.

During the past decades, emission of greenhouse gases has accelerated to unsustainable levels. This is a serious issue that can have a devastating impact on everything from global economy to the terrestrial or marine ecosystem. A method for reducing the emission is named carbon capture and storage, which this project is based on. In this study, different concentrations of citric acid (CA) is used (as an additive) for the enhancement and optimization of carbon dioxid sorption properties of amorphous calcium carbonate (ACC), mesoporous magnesium carbonate (MMC) and calcium magnesium carbonate composite (CMC). These materials were heat treated in a calcination and an alternating carbonation process in order to study the carbon dioxid sorption performance. During the calcination process, CA undergoes a pyrolysis reaction in order to increase the specific surface area of the individual nanoparticles, which is an important factor for the sorption capacity. In the case of CMC, different molar ratios of magnesium oxide and calcium oxide were used in order to alter the concentration of the resulting magnesium oxide prior to heating. All three materials consisted of aggregations of nanometer-sized particles. Thermogravimetric analysis, scanning electron microscopy, surface area and porosimetry and infrared spectroscopy analysis suggest that the carbon dioxid sorption properties and the sintering stability of ACC and MMC do not improve since CA evaporates due to pyrolysis. Sintering was a greater problem for the evaluated CA treated ACC sample. However, in the case of CMC, the sorption and sintering properties were enhanced due to the higher Tamman-temperature of magnesium oxide, specifically for the lower concentration of magnesium oxide. After 19 carbonation cycles, CMC-1:1-25% CA showed signs of improved sintering stability and sorption capacity, compared to ACC-75% CA. / <p>Presentationen genomfördes på distans.</p>

In this thesis, the incorporation of drug loaded mesoporous magnesium carbonate as an excipient for the additive manufacturing of oral tablets by fused deposition modeling was investigated. Cinnarizine, a BCS class II drug, was loaded into the pores of the mesoporous material via a soaking method, corresponding to a drug loading of 8.68 wt%. DSC measurements on the loaded material suggested that the drug was partially crystallized after incorporation, meanwhile the XRD diffractogram implied that the drug was in a state lacking long range order. The drug loaded material was combined with two pharmaceutical polymers, Aquasolve LG and Klucel ELF, and extruded into filaments with a single screw extruder. Filaments of Klucel ELF and drug loaded Upsalite (30:70 wt% ratio) were successfully implemented for the printing oral tablets, in contrast to the Aquasolve LG based filaments which were difficult to print due to thickness variations and non-uniform material distributions. The drug content obtained by TGA suggested drug loadings of 7.71 wt% and 2.23 wt% in the drug loaded Upsalite and tablets respectively. Dissolution studies using an USP II apparatus showed a slower API-release from the tablets in comparison to the crystalline drug, most probably due to slow diffusion of drug species through the polymeric matrix. For future studies, pharmaceutical polymers with higher aqueous solubility should be investigated in order to thoroughly examine the potential of utilizing the immediate release property of Upsalite.

PureFize Technologies AB develops and manufactures a broadband ultraviolet (UVC) light technology device that is mercury-free and based on nanotechnology, using the principle of field emission. The light source is made of Ti and glass, which are hermetically bonded, using a low-temperature glass frit, at elevated temperatures. The bonding procedure will induce stresses in the device originating from the mismatch of the coefficient of thermal expansion (CTE) between the materials. Brittle materials, as glass, withstands tensile stresses poorly. Therefore, the stress magnitude and distribution needs to be understood.  This work develops a quality inspection method for the glass bond and internal stresses, as well as stress simulations of the device, to be used in production at the company. The glass bond width and the internal stresses in the device were classified and analyzed by light optical microscopy and by polarised light optical microscopy. The optical analysis was followed by pressure tests of the devices using a chamber that allowed for pressurized air up to 7 bar. In parallell with the experimental work, stress and deformation simulations of the device using the finite element method (FEM) was made. Data collected from the inspections and pressure tests were compiled and analyzed, showing clear connections between the glass bond quality and the device's ability to withstand external pressure. A narrow glass bond could withstand external pressure poorly, whereas a wide glass bond could withstand external pressure well. Correlations could be made both between the glass bond appearance and the stress patterns, as well as between the FEM simulations and the stress patterns in the device. It is clear that the stresses induced in the device after bonding originates from the CTE mismatch of the bonded components when cooling it from the bonding temperature to room temperature. The pressure testing method proved to be an efficient way of verifying the maximum pressure capacity of the devices.  The knowledge from this thesis can be used when further investigating induced stresses from glas frit bonding.

Coil coatings are durable  organic coatings used to protect metal sheets from corrosion and improve their aesthetic properties. Because of their extensive use, coil coatings have long been of interest for industrial and academic researchers. This interest has recently been furthered by a societal push towards the replacement of fossil-based raw materials with alternatives that are biobased and renewable. The aim of this licentiate thesis is to demonstrate how analyses on the macro-, micro-, and nanoscale can be used to better understand the degradation process of polyester-based coil coatings. The included manuscripts showcase methods for evaluating and comparing different coil coating formulations and for verifying accelerated weathering techniques. Multiple techniques, focusing on infrared (IR) spectroscopy and atomic force microscopy (AFM), were used to analyze coating systems before and after different types of weathering. IR data acquired from techniques without spatial resolution, such as attenuated total reflection (ATR) and photoacoustic spectroscopy (PAS) have been expanded upon with spatially resolved focal plane array (FPA) and s-SNOM  (scattering-type scanning near-field optical microscopy) measurements. Spatially resolved chemical data of coating cross sections were acquired and used to assess how the degradation at the surface and in the bulk was related. Additionally, differences between the degradation behavior of a standard fossil-based coating and a similar coating with biobased components as well as differences between the degradation caused by artificial and natural weathering was discussed. Nanoscale mechanical measurements of simplified coating surfaces showed that weathering increased nanomechanical stiffness and led to homogenization of mechanical properties on the local level. In addition, measurements with nanoscale FTIR correlated with macroscale FTIR. Even relatively minor changes in band intensities could be tracked on a local scale. Although the simplified samples were chemically homogeneous, nanoscale FTIR shows great promise for the assessment of local degradation of full systems. / Bandlackering är en process för att applicera stabila organiska beläggningar på metallytor för att skydda från korrosion och förbättra deras utseende. På grund av beläggningarnas omfattande användning så har utvärdering och analys av dem varit av intresse för både akademi och industri i flera årtionden. Detta långvariga intresse har ytterligare främjats av en ökade miljömedvetenhet och ett tryck att ersätta miljöfarliga och fossila råmaterial mot biobaserade och förnyelsebara alternativ. Målet med denna licentiatavhandling är att visa hur analysmetoder på makro-, mikro-, och nanonivå kan användas för att bättre förstå nedbrytning av bandlackerade beläggningar. Denna förståelse kan användas både för att utvärdera prestandan hos både nya redan befintliga system, men också för att kunna verifiera accelererade testmetoder vars mål är att minska tiden som krävs för utvärdering. Flera tekniker, med fokus på infraröd (IR) spektroskopi och atomkrafts-mikroskopi  (AFM) använts för att analysera beläggningar före och efter att de blivit utsatta för olika typer av aggressiva miljöer. Spektroskopiska data utan spatial upplösning som attenuerad totalreflektions FTIR (ATR) och fotoakustisk spektroskopi (PAS) har kompletterats med spatialt upplösta fokalplans array (FPA) och s-SNOM mätningar. Kemisk information med spatial upplösning har använts för att utvärdera hur nedbrytningen nära ytan relaterade till nedbrytningen längre ner i beläggningen. Likheter och skillnader i nedbrytningen som skedde i en standardbeläggning och ett system med biobaserade additiv jämfördes efter både väderbestendighets-testning som skedde utomhus och i labb. Skillnader mellan dessa exponeringsmetoder diskuterades också. Nanomekanisk analys med hjälp av atomkraftsmikroskopi användes för att bestämma lokala förändringar av mekaniska egenskaper i förenklade klarlacker. Mätningarna visade att exponeringar i aggressiva miljöer leder till en lokal homogenisering av mekaniska egenskaper och ökad styvhet. Utöver detta så utvärderades likheter och skillnader mellan FTIR spektra som tagits på makro- och nanonivå. Dessa mätningar gav lovande resultat för fortsatta ytanalyser. / <p>QC 2023-05-15</p>

The project aims to develop a methodology to study the variation in properties of wood polymer composites (WPC’s) with/without surface treatment at different humidity conditions. The project aims to investigate the behavior of biocomposites at 50%, 80%and 100% relative humidity (RH). Also to clarify if the hydrophilization effect helps to preserve the structural integrity of the materials for longer periods at these conditions. The comparison between biocomposites comprising polypropylene (PP) with both untreated wood fibers (WF) or FibraQ (hydrophobic surface-treated wood fibers from Biofiber Tech) was made. The focus was on the mechanical properties, water absorption, macro- and microstructures. The results show that PP comprising FibraQ exhibits lower moisture uptake than the PP comprising untreated WF at high relative humidity conditions. The mechanical properties did not seem significantly affected by the surface treatment at high relative humidity conditions. It is also concluded that since the study only ran for four weeks, there was not enough time to fully understand the influence of moisture uptake over the materials’ properties.