New lyotropic nematics of double chain surfactants
New lyotropic nematics of double chain surfactants
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DOI：
10.1080/02678298908045696
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发表时间：
1989-12
期刊：
影响因子：
2.2
通讯作者：
G. Hertel;H. Hoffmann
中科院分区：
文献类型：
--
作者：
G. Hertel;H. Hoffmann
本文用偏光显微镜、2 H-N. M. R.等研究了N，N-二烷基-N，N-二甲基溴化铵双链表面活性剂的相行为。光谱，表面和磁场排列，以找到新的溶致液晶系统。癸醇用于在正相中引起棒到盘的转变。通过用苯磺酸根离子取代溴抗衡离子，反磁化率Δx的各向异性的符号被反转。通过改变两个烷基链的长度，在很宽的范围内改变相行为。使用这些工具，我们能够制备任何的四种单轴取向相：棒状和盘状聚集体的抗磁磁化率的负和正各向异性。介绍了几种新的双链表面活性剂的二元、三元和四元体系，并对不同的双链表面活性剂相进行了分类。
Abstract The phase behaviour of N,N-dialkyl-N,N-dimethyl ammonium bromide double chain surfactants was investigated by polarization microscopy, 2H-N.M.R. spectroscopy, and surface and magnetic field alignment in order to find new lyotropic nematic systems. Decanol was utilized to cause a rod to disc transition in the nematic phase. The sign of the anisotropy of the diamagnetic susceptibility Δx was inverted by substituting the bromide counter-ion with the benzenesulphonate ion. The phase behaviour was modified within a wide range by varying the length of the two alkyl chains. Using these tools we were able to prepare any of the four kinds of uniaxial nematic phases: rod-like and disc-like aggregates with both negative and positive anisotropy of the diamagnetic susceptibility. Several new binary, ternary and quaternary systems of these double chain surfactants and some experiments are described to classify the different nematic phases.