Thermal and optical properties of some hydrogen-bonded liquid crystal mixtures
Yükleniyor...
Tarih
2014
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
SPRINGER
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Phase transition properties of the mixtures of hydrogen-bonded nematic liquid crystals (HBLC) 4-hexylbenzoic acid (6BA), 4-(octyloxy)benzoic acid (8OBA), and 4-(decyloxy)benzoic acid (10OBA) have been investigated by means of differential scanning calorimetry (DSC) and polarize optic microscope (POM). The DSC and POM results clearly indicate the existence of smectic and nematic phase transitions in binary mixtures. The phase transition temperature values of 6BA/10OBA mixtures have clearly increased with increasing heating rate. The activation energies were calculated for the phase transitions of 6BA/10OBA liquid crystal (LC) mixture. The optical transmittance of these mixed hydrogen-bonded nematic liquid crystals was investigated in terms of temperature variations through electrooptic methods. The electrooptic experiments indicate that, while low in the nematic phase, the optical transmittance is very high at the nematic-isotropic phase transition. The transmitted light intensity values of 6BA/8OBA mixture are somewhat higher than those of other binary mixtures, 6BA/10OBA and 8OBA/10OBA, a result associated with the different alkyloxy chain lengths.
Açıklama
Anahtar Kelimeler
Liquid Crystal Mixtures, Thermodynamic Properties, Optical Properties
Kaynak
BRAZILIAN JOURNAL OF PHYSICS
WoS Q Değeri
N/A
Scopus Q Değeri
Q3
Cilt
44
Sayı
4
