Effect of the surfactant alkyl chain length on the stabilisation of lyotropic nematic phases
Yükleniyor...
Dosyalar
Tarih
2018
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Taylor & Francis Ltd
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Lyotropic quaternary mixtures of potassium alkanoates (KCx) and sodium alkyl sulphates (NaCxS), where x is the number of carbon atoms in their alkyl chains, were prepared to investigate the effect of the surfactant alkyl chain length on the stabilisation of lyotropic nematic phases. The lyotropic mixtures investigated were formed by the dissolution of KCx (NaCxS) surfactants in the mixture of Rb2SO4/1-decanol/water (Na2SO4/1-decanol/water), separately. The uniaxial-to-biaxial nematic phase transitions were identified from the temperature dependence of the birefringences of the nematic phases by means of laser conoscopy. The micelle dimensions were obtained from small-angle X-ray scattering measurements. It was observed that the increase in the surfactant alkyl chain length causes the micellar growth in the plane perpendicular to the main amphiphile bilayer. The surfactant alkyl chain length plays a key role on the shape anisotropy of micelles, which triggers the orientational fluctuations that are responsible for the stabilisation of the different lyotropic nematic phases. [GRAPHICS] .
Açıklama
Anahtar Kelimeler
Lyotropic Nematic Phases, Surfactant Alkyl Chain Length, Phase Transition, IBM model of nematic phases, Laser Conoscopy, Small-angle X-ray Scattering
Kaynak
Liquid Crystals
WoS Q Değeri
Q2
Scopus Q Değeri
Q2
Cilt
45
Sayı
2
