Role of kosmotrope-chaotrope interactions at micelle surfaces on the stabilization of lyotropic nematic phases
Yükleniyor...
Dosyalar
Tarih
2016
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Springer
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Three lyotropic quaternary systems of ionic surfactants were prepared to investigate the role of kosmotrope-chaotrope interactions at the micelle surfaces on stabilizing the different nematic phases. The ionic surfactants were potassium laurate (KL), sodium dodecylsulfate (SDS) and tetradecyltrimethylammonium bromide (TDTMABr), where KL is a kosmotrope surfactant, and others are chaotrope. The first system consisted of KL/decanol (DeOH)/water/alkali sulfate and the second of SDS/DeOH/water/alkali sulfate. The third system was prepared by adding sodium salts of chaotropic or kosmotropic anions to the primary mixture of TDTMABr/DeOH/water, separately. The characteristic textures of discotic nematic (N (D)), biaxial nematic (N (B)) and calamitic nematic (N (C)) phases were identified under polarizing light microscope. Laser conoscopy was employed to determine the uniaxial-to-biaxial phase transitions. The kosmotrope-kosmotrope or chaotrope-chaotrope interactions between the head groups of the surfactants and the ions of the electrolytes led to the stabilization of the N (D) phase. On the other hand, kosmotrope-chaotrope interactions stabilize the N (B) and/or N (C) phases.
Açıklama
Anahtar Kelimeler
Lyotropic Nematic Phases
Kaynak
European Physical Journal E
WoS Q Değeri
Q3
Scopus Q Değeri
Q2
Cilt
39
Sayı
107
