104-43-8Relevant articles and documents
Controlling the formation of heliconical smectic phases by molecular design of achiral bent-core molecules
Alaasar, Mohamed,Cai, Xiaoqian,Eremin, Alexey,Kurachkina, Marharyta,Lehmann, Anne,Liu, Feng,Nagaraj, Mamatha,Poppe, Marco,Poppe, Silvio,Tamba, Maria-Gabriela,Tschierske, Carsten,Vij, Jagdish K.
supporting information, p. 3316 - 3336 (2020/03/23)
Fluids with spontaneous helical structures formed by achiral low molecular mass molecules is a newly emerging field with great application potential. Here, we explore the chemical mechanisms of the helix formation by systematically modifying the structure of a bent 4-cyanoresorcinol unit functionalized with two different phenyl benzoate based aromatic rods and terminated with two alkyl chains of variable length. The majority of these achiral compounds self-assemble, forming a short-pitch heliconical liquid crystalline phase in broad temperature ranges. In some cases, it occurs without any competing low-temperature phase. We demonstrate that the mirror symmetry broken mesophase occurs at the paraelectric-(anti)ferroelectric transition if the tilt angle of the molecules in the smectic layers is around 18-20° and if this transition coincides with a change of the tilt correlation between the layers. In the close vicinity of this transition, a field-induced heliconical phase develops as well as a new heliconical phase with polarization-randomized structure. These investigations provide a blueprint for the future design of achiral molecules capable of spontaneous mirror symmetry breaking by the formation of heliconical liquid crystalline phases.
Head group specificity of novel functionalized surfactants: Synthesis, self-assembly and calcium tolerance
Sarkar, Deboleena,Shukla, Ravi Kant,Gadgil, Vijay,Pramanik, Amitava
, p. 5925 - 5931 (2015/01/16)
The present work describes the synthesis, characterization and application of functionalized surfactants derived through simple organic reaction steps. These surfactants have been particularly tailor made to resist hardness due to calcium ions in water. It is unique of its kind because here the surfactants have an analogous hydrophobic chain but differ structurally in the composition of the head groups in terms of the position of attachment of the chain. The effect of this small variability in the head group on the surfactant property, adsorption, self assembly and calcium tolerance behaviour has been studied in detail. This kind of phenol-keto surfactants has not been reported before. It was also found that one of the surfactants was more tolerant towards Ca2+ion than the other. The individual packing behaviour of the surfactants at the air-water interface has been projected to cause this difference which is very interesting.
Synthesis and critical micelle concentration of a series of gemini alkylphenol polyoxyethylene nonionic surfactants
Yang, Fang,Li, Gang,Xu, Nian,Liu, Rong,Zhang, Song-Mei,Wu, Zeng-Jiang
experimental part, p. 339 - 345 (2012/06/30)
A series of gemini n-alkylphenol polyoxyethylene surfactants (GAP) were successfully synthesized and their molecular structure were confirmed by NMR and FTIR spectrum. Using the same synthesis route, a Gemini nonylphenol polyoxyethylene surfactant (GNP) was synthesized using an industrial nonylphenol product and paraformaldehyde, and its molecular structure was also characterized by 1H-NMR and FTIR spectra. The optimal reaction conditions were established. The critical micelle concentration (CMC) values of GAP were determined by means of Wilhelmy plate method and steady-state fluorescence probe method. The experimental results show how the lengths of the hydrophilic polyoxyethylene chain and the hydrophobic tail alter the CMC values. The CMC values of the GAP are found to be much lower than those of corresponding conventional single tail nonionic surfactants of the polyethoxylated alkylphenol type, which indicates that the gemini species exhibit a better surface activity. AOCS 2011.
