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Bitumen with 50/70 penetration was prepared and modified by doping with the unsaturated polyester resin based on isophthalic acid at 5% by weight (w/w%). The structural, mechanical, and thermal properties of bitumen and bitumen modified with unsaturated polyester resin %5 (UPR) were determined. The dielectric properties of bitumen and modified bitumen were investigated in the frequency and temperature ranges of 0.1-106 Hz and (-)40°C- 40°C, respectively. Polarization mechanisms, glass-transition temperature, and ductility of all samples were determined and compared to each other. The glass transition temperature of the modified bitumen shifts toward low temperatures in comparison to the bitumen. So, it can be suggested that the use of modified bitumen is very attractive in regions where the temperature differences are high. Also, the dielectric analysis method is an innovative alternative to determining modified bitumen's low-temperature performance. It was found that the modification with UPR provide strength and flexibility to asphalt. [ABSTRACT FROM AUTHOR]

Bulk TlGaS 2 single crystals were produced by the Bridgman method. TlGaS 2 thin film samples were deposited from bulk crystals by the thermal evaporation technique under a high vacuum. TlGaS 2 thin films were deposited in the 100–750 nm thickness range. Dielectric spectroscopy measurements were operated in the frequency range of 1–105 Hz and temperature range of 273–373 K under the voltage of 1 V (rms). TlGaS 2 thin films have amorphous. Bulk TlGaS 2 has a crystalline structure based on X-Ray diffraction patterns. Three polarization mechanisms were detected from the analysis of Cole-Cole plots. At low frequencies, the effect of interfacial polarization was observed. Toward higher frequencies, two dipolar polarization mechanisms were detected. In comparison to the bulk TlGaS 2 single crystal, the dielectric constant of the thin films has 100–1000 times larger values at frequencies lower than 100 Hz. The thickness limit at which bulk physical properties started has been investigated. The transition thickness between bulk/thin film properties was detected at around 700 nm. The low dielectric constant and the good conductivity around 10−8 S/cm at105 Hz can give opportunities to use these thin films in technological applications. • The interfacial polarization is observed at frequencies lower than 100 Hz. • At higher frequencies, polarization mechanisms having dipolar nature are detected. • At frequencies below 100 Hz, the dielectric constant has 100–1000 times greater values for TlGaS 2 thin films. • The dielectric properties of TlGaS 2 thin films change to bulk dielectric properties with thickness-independent dielectric behavior at 800 nm. • TlGaS 2 thin films are suitable for nano-sized switching and thermoelectric applications. [ABSTRACT FROM AUTHOR]

Plasma polymerized poly(ethylene oxide) thin film samples with thickness of 500 nm were deposited using plasma assisted physical vapour deposition at radio-frequency plasma discharge powers of 0, 2, 5 and 30 W, respectively. For comparison, a conventional poly(ethylene oxide) precursor was also investigated. In order to investigate the effect of the plasma discharge power on the cross-linking density of the plasma poly(ethylene oxide) and poly(ethylene oxide) precursors, structural characterization using differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy was performed. Structural analysis showed that the density of cross-linking increased upon increasing the plasma discharge power. This increase was observed as an increase in the dynamic glass transition temperature during the DSC measurements. In addition to these characterizations, the dielectric response of the thin film plasma poly(ethylene oxide) samples and poly(ethylene oxide) precursors were measured. The dielectric spectroscopy results showed that changes in the cross-linking density changed the alternative current (AC) conductivity. The measured glass transition temperatures obtained using DSC are in accordance with the glass transition temperatures obtained from the temperature-dependent AC conductivity results. It was observed that the temperature-dependent AC conductivity exhibits Arrhenius behaviour. The activation energies obtained for the plasma polymer samples showed an increase from 0.38 eV to 0.5 eV upon increasing the plasma discharge power. The plasma discharge power dependent activation energy results also indicate the fragmentation of long polymer chains into more smaller oligomers and radicals occurred upon increasing the plasma power. [ABSTRACT FROM AUTHOR]