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This diploma thesis covers the tracking of final quality parameters of polyether polyol – Slovaprop G-160, which are: amount of sodium and potassium, color, acidity and amount of water. The most important parameter was the amount of sodium and potassium, because the aim this thesis was to achieve satisfactory amount of sodium and potassium after the purification process with use of zeolite (ZeoCem Micro 200) and to improve the effectivity of the purification and filtration process in the production of polyether polyol – Slovaprop G-160. In theoretical part, Diploma thesis deals with the method of production and characteristics of polyether polyols for the production of polyurethane foams. Practical part consists of nine series of experiments in order to get addictions of amount of sodium and potassium to temperature, weight of Pyrofos and amount of zeolite. Based on laboratory test a new way of purification process of polyether polyols was developed. With this new purification process the production time of Slovaprop G-160 will be shorten thanks to removal of hydrolysis from the reaction process and in the end of the process the time needed for drainage is reduced in half.

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Pressing demands for high power and high energy densities in novel electrical energy storage units have caused reconsiderations regarding both the choice of battery chemistry and design. Practical concerns originating in the conventional use of flammable liquid electrolytes have renewed the interests of using solvent-free polymer electrolytes (SPEs) as solid ionic conductors for safer batteries. In this thesis work, SPEs developed from two polymer host structures, polyethers and polycarbonates, have been investigated for all-solid-state Li- and Li-ion battery applications. In the first part, functional polyether-based polymer electrolytes, such as poly(propylene glycol) triamine based oligomer and poly(propylene oxide)-based acrylates, were investigated for 3D-microbattery applications. The amine end-groups were favorable for forming conformal electrolyte coatings onto 3D electrodes via self-assembly. In-situ polymerization methods such as UV-initiated and electro-initiated polymerization techniques also showed potential to deposit uniform and conformal polymer coatings with thicknesses down to nano-dimensions. Moreover, poly(trimethylene carbonate) (PTMC), an alternative to the commonly investigated polyether host materials, was synthesized for SPE applications and showed promising functionality as battery electrolyte. High-molecular-weight PTMC was first applied in LiFePO4-based batteries. By incorporating an oligomeric PTMC as an interfacial mediator, enhanced surface contacts at the electrode/SPE interfaces and obvious improvements in initial capacities were realized. In addition, room-temperature functionality of PTMC-based SPEs was explored through copolymerization of ε-caprolactone (CL) with TMC. Stable cycling performance at ambient temperatures was confirmed in P(TMC/CL)-based LiFePO4 half cells (e.g., around 80 and 150 mAh g-1 at 22 °C and 40 °C under C/20 rate, respectively). Through functionalization, hydroxyl-capped PTMC demonstrated good surface adhesion to metal oxides and was applied on non-planar electrodes. Ionic transport behavior in polycarbonate-SPEs was examined by both experimental and computational approaches. A coupling of Li ion transport with the polymer chain motions was demonstrated. The final part of this work has been focused on exploring the key characteristics of the electrode/SPE interfacial chemistry using PEO and PTMC host materials, respectively. X-ray photoelectron spectroscopy (XPS) was used to get insights on the compositions of the interphase layers in both graphite and LiFePO4 half cells.

Oxidative degradation of adhesives based on silane terminated polypropylene oxide and polypropylene oxide (PPO) was studied. The combination of rapeseed oil and PPO as plasticizer in the parquet adhesive gave rise to oxidative degradation in contact with screeds of certain minerals. In order to investigate the degradation process in parquet adhesive two experimental approaches were employed in parallel. The first method was ageing of a solid adhesive-screed system at elevated temperature. It was done in order to evaluate the effect of contact between adhesives and screed in different adhesive-screed systems. Another purpose was also to identify the degradation procedure in a system resembling reality. The second method used was ageing of a soluble mixture of pure PPO with selected plant oils; in order to study the affect of oils unsaturations on the PPO by FTIR. FTIR was used to monitor the degradation of samples after different exposure periods. Unfortunately, interference from the adhesive additives made monitoring of the degradation process difficult in this approach. On the other hand, the optical inspection of the samples degradation process gave a clearer overview. A second method, looking only at two components mixed e.g. PPO and Oil, gave clear FTIR spectra showing that the oxidation process of rapeseed oil started in the period before fifteen days ageing at 75 oC. The combination of FTIR and optical inspection gave a clear image of the adhesive degradation process. Interaction between unsaturated carboxylic acid in the vegetable oils and PPO can increase the degradation rate of parquet adhesives by a radical mechanism. Another parameter affecting the degradation is the interfacial interaction between adhesive containing PPO-Rapeseed oil as plasticizer and screed with high alkalinity, porosity and humidity. The alkaline and humid conditions in the screed probably increase the hydrolysis of rapeseed oil. Further, the porosity of the screed provides a large surface area enabling the plasticizer to be exposed to plenty of oxygen from the air. Therefore, the plasticizer is not only exposed to hydrolysis but also oxidation. This would support the observation of migration of the rapeseed oil, since it is known that carboxylic acid has affinity to calcium sulfate anhydrite in the screed material. Migration and oxidation of rapeseed oils carboxylic acid generate radicals, which accelerate the degradation of PPO in the adhesive film. This process correlated with disappearance of PPO absorbance band from the spectrum.

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Many pathogenic bacteria can enter phagocytic cells and replicate in them, and these intracellular bacteria are difficult to treat because the recommended antibiotics do not transport into the cells efficiently. Examples include food-borne bacteria such as Salmonella and Listeria as well as more toxic bacteria such as Brucella and the Mycobacteria that lead to tuberculosis. Current treatments utilize aminoglycoside antibiotics that are polar and positively charged and such drugs do not enter the cells in sufficient concentrations to eradicate the intracellular infections. We have developed core-shell polymeric drug delivery vehicles containing gentamicin to potentially overcome this challenge. Pentablock and diblock copolymers comprised of amphiphilic nonionic polyether blocks and anionic poly(sodium acrylate) blocks have been complexed with the cationic aminoglycoside gentamicin. The electrostatic interaction between the anionic polyacrylates and the cationic aminoglycosides form the cores of the nanoplexes, while the amphiphilic nature of the polyethers stabilize their dispersion in physiological media. The amphiphilic nature of the polyethers in the outer shell aid in interaction of the nanoplexes with extra- and intra-cellular components and help to protect the electrostatic core from any physiological media. This thesis investigates the electrostatic cooperativity between the anionic polyacrylates and cationic aminoglycosides and evaluated the release rates of gentamicin as a function of pH. / Master of Science

New compounds consisting of 3-thienyl and aniline units linked by polyether bridges have been synthesized and their electrochemical polymerization was performed via constant potential electrolysis and cyclic voltammetry. In the case of 3-thienyl derivatives two compounds, 1,12-di-3-thienyl-2,5,8,11-tetraoxadodecane (MI) and 1,15-di-3-thienyl-2,5,8,11,14-pentaoxapentadecane (MII) were synthesized utilizing literature methods and their corresponding polymers, poly(I) and poly(II) were prepared in an electrolytic solution containing 0.1 M terabutylammonium hexafluorophosphate (TBAPF6) dissolved in CH3CN. On the other hand, polymerization of aniline derivatives, 2,2&#039 / -[ethane-1,2-diylbis(oxyethane-2,1-diyloxy)]dianiline (MIII) and 2,2&#039 / -[oxybis(ethane-2,1-diyloxyethane-2,1-diyloxy)]dianiline (MIV), was achieved in an aqueous solution containing 3.0 mol.L-1 H2SO4. Spectroelectrochemical (SPEL) properties and thermal analysis of the resulting polymers have been investigated using UV-vis, and Thermogravimetric Analysis (TGA). MIII was also polymerized via chemical oxidation for comparison purposes. The polymers were characterized using 1H-NMR and FT-IR spectroscopic techniques. Furthermore, copolymers of MIII and MIV with aniline (ANI) were also studied with cyclic voltammetry (CV). SPEL behavior and electrical conduction mechanism of resulting copolymers were investigated using UV-vis spectroscopic technique and four-point probe technique, respectively.