Study On The Glass Transition Of Ethanol Aqueous By Dielectric Spectroscopy

The glass transition is one of the most challenging problems in condensed matter physics, and it hasnot been resolved for a long time more than half a century. Scientist has been constantly trying to use avariety of experimental techniques to study the glass transition from different angles because they areInevitably in giving important information about the glass transition from a new perspective. Among thema large number of studies have shown that the dielectric spectroscopy method is an effective means to studythe glass transition. This thesis is commenced/unfold through the study of dielectric spectra in the glasstransition process.Based on dielectric spectroscopy method for the properties of the ethanol aqueous, A dielectricspectroscopy method was applied to the liquid glass transition experimental devices and experiments. Thedielectric spectroscopy Covers the frequency range of100~106Hz of magnitude. The experimentalconditions were as follows: liquid nitrogen as a cold source, cooling method for a given rate of cooling, thecooling rate of about1K/min of cooling range at293K~90K. The experimental results show that:1) Thereal and imaginary parts of complex permittivity of the aqueous solutions of different concentrations ofethanol in the cooling process (arbitrary units) changes in relations with the temperature T, the real part hastwo main changesK andC d, there are two main changesP andLd at the imaginary part.K iswith stepped changes with T,P is the loss peak,C dandLd are the diffusion of ions due to impuritiesin the material.2) The volume ratio of50%,70%,80%aqueous ethanol solution of the complexpermittivity imaginary part corresponding with the change of temperature T, showing two consumptionpeaks. Make these two the average time of relaxation processes and T, respectively, in accordance with theVogel-Fulcher-Tamman’s law and equation Arrhenius volume.3)It is shown that the relationship betweendifferent concentrations of the real part of complex permittivity and different concentrations of ethanol,water-soluble phase change at the same frequency, the imaginary part of complex permittivity with thetemperature T changes.It can obtain the function between the average time of the relaxation process and T,and thefunction between the temperature to the imaginary part of the loss peak corresponding at differentfrequencies and frequency. The functions are positioned to meet the Vogel-Fulcher-Tamman’s law andVogel-Fulcher’s law well. It reflects that the experimental data is desirable. The article also explained fromthe microscopic mechanism of the trend of the real and imaginary part of the dielectric constant.This research work has shown that it is feasibility and effectiveness by using the method of dielectricspectroscopy to study the glass transition of the ethanol solution, and has summarized the some of theregularity knowledge. This study will provide some experimental basis for the ethanol solution of the glasstransition theory and accumulate experimental measurement and data analysis experience for study asimilar system. The results are also going to help to explore the mechanism in further in the glass change.