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## Zastosowanie cieczy jonowych w elektrolitach polimerowych

### Anita Pawlak

#### Abstract

The development of mobile electronic devices, such as mobile phones and cameras, resulted in demand for batteries with higher efficiencies, with a simultaneous low mass of those devices. The answer to those needs is lithium-ion batteries. In recent years, intense research has been conducted in order for batteries to be as safe as possible during use [1]. When it comes to safety, good properties are displayed by solid polymer electrolytes, however, they display an ionic conductivity that is too low for practical use. Another solution is to use ionic liquid as a component of electrolytes, which can substitute volatile and combustible organic solvents. This engineering thesis is dedicated to acquiring new, ionic liquid lithium salts, which can be potentially used in the electrolytes of lithium-ion batteries. The first stage of my research was to obtain tri-alkoxy-boron derivatives [CH3O(CH2CH2O)n]3B with a different length of the oxiethylene chain, n=1,2,3 and 7,5. In the tri-alkoxy-boron synthesis, as reactants, I have used B2O3 and monoethers of appropriate oxiethylene glycols. The next stage of the synthesis was to obtain alkoxide. For this, a reaction was carried out between n-BuLi and an appropriate glycol. The two reactants, acquired this way, were subjected to reaction, between themselves, in order to obtain lithium salt. The obtained salts were subjected to NMR, FTIR and thermal spectral characteristics using differential scanning calorimetry (DSC). In 11B NMR spectra of the obtained salts, I have observed that the peak deriving from boron is changing its position, from a displacement that is characteristic for tri-coordinate boron in tri-alkoxy-boron used as the reactant, to a displacement characteristic for tetra-coordinate boron in the expected lithium salt. I have observed that these compounds present ionic liquid properties, of which viscosity increases along with the chain length. At the next stage of my experiment, I have decided to check if, through the reaction of 2-(hydroxyethyl)methacrylate (HEMA) with tri-alkoxy-boron, there is a possibility to introduce groups, which are capable of polymerisation, to the lithium salt. For this, I have conducted a reaction between HEMA and n-BuLi in order to obtain lithium alkoxide, and then, I have added a derivative of tri-alkoxide. The spectral analysis has confirmed the assumed course of reaction. I have also conducted attempts of radical polymerisation of the obtained derivative, however, I have not obtained a polymer. The process of polymerisation requires further research. The results, obtained as part of my thesis, indicate wide range of capabilities for the modification of tetra-alkoxy-boron salt by creating different combinations of oxiethylene chains. The used synthesis method allows for the introduction of different functional groups to the boron anion.
Diploma type
Engineer's / Bachelor of Science
Diploma type
Engineer's thesis
Author
Anita Pawlak Anita Pawlak,, Undefined Affiliation
Supervisor
Ewa Zygadło-Monikowska (FC/CPCT) Ewa Zygadło-Monikowska,, Chair Of Polymer Chemistry And Technology (FC/CPCT)Faculty of Chemistry (FC)
Certifying unit
Faculty of Chemistry (FC)
Affiliation unit
Chair Of Polymer Chemistry And Technology (FC/CPCT)
Study subject / specialization
, Technologia Chemiczna
Language
(pl) Polish
Status
Finished
Defense Date
05-02-2016
Issue date (year)
2016
Keywords in Polish
x
Keywords in English
x
Abstract in Polish
urn:pw-repo:WUT9079219a8985447ea14e6e411797ac58