The mechanisms of the deterioration of cellulose acetate compounded with triphenyl phosphate were investigated. A key peak shift of 726cm⁻¹ to 718cm⁻¹ in the Raman spectrum of triphenyl phosphate (726cm-1 uncompounded) when compounded in cellulose acetate (718cm⁻¹) was tied to the action of C-O bonds in triphenyl phosphate. The molecular bonds responsible for the 726cm⁻¹ peak were identified by collecting and examining spectra of chemicals with functional groups similar to triphenyl phosphate. Initially it was hypothesized that triphenyl phosphate acts as nucleophilic catalyst of deacetylation. This mechanism was evaluated by dissolving triphenyl phosphate in solvents that served as functional group analogues of cellulose acetate. These liquid-solution systems have a faster rate of reaction and complete mixing with triphenyl phosphate compared with what is seen in cellulose acetate solid-solution systems. The results of the cellulose acetate analogue experiments did not support the hypothesis of triphenyl phosphate acting as a nucleophilic catalyst of deacetylation. The results instead support a new theory of deterioration induced by the recrystallization of triphenyl phosphate. Additionally, the prevailing theory of triphenyl phosphate induced deterioration as proposed by Shinagawa et al. in 1992 was reviewed. The experiments conducted here do not support Shinagawa's theory.

The thesis is devoted to the field of properties investigation of new types of electrolytes, and assess the appropriateness of electrolytes studied in this paper for use in Li -ion batteries. It focuses specifically on electrolytes based on aprotic solvents and their mixtures with the flame retardants. The goal of the thesis is to investigate the effects of FRAs on electrolyte mixtures via changes in specific conductivity and freezing point. These objectives were fulfilled by using electrochemical impedance spectroscopy in combination with a cryoscopic measurement method. There were overall 16 samples examined. The samples were prepared as a combination of chemicals, specifically Ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), dimethyl sulfone (DMSO2), triethyl phosphate (TEP) Dimethyl methylphosphonate (DMMP), triphenyl phosphate (TPP). Based on the results of the experiments, the mixtures were sorted according to the observed properties in the tables listed in the last part of this paper. These values can be further used to supplement the continuing research of electrolytes and also as assistance in searching for the new electrolyte mixtures.

This thesis deals with liquid aprotic electrolytes based on sulfolane with added flame retardant. The theoretical part of the thesis explains concepts - mainly aprotic electrolytes, flame retardants, and their practical use. It also discusses lithium - ion accumulators and materials used in them while focusing on the electrolyte function. The practical part of the thesis aims to measure the properties of aprotic electrolytes: their conductivity, potential window and flashpoint. It also contains a review of the measurement results.