Effects of temperature and shear conditions on lamellar-to-onion transition in nonionic surfactant/water systems
Effects of temperature and shear conditions on lamellar-to-onion transition in nonionic surfactant/water systems
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温度和剪切条件对非离子表面活性剂/水体系中层状到洋葱转变的影响
DOI：
10.1016/j.colsurfa.2022.130755
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Takahashi Tsutomu
中科院分区：
文献类型：
--
作者：
Hatakeyama Kota;Yamagata Yoshifumi;Takasaki Yuichi;Miyamoto Keisuke;Takahashi Tsutomu
温度和剪切条件对层状到多层囊泡（MLV）相变的影响使用流变仪（Rheo）-小角光散射（SALS）测量来阐明，所述测量用于包括C12E4.2（含有分布的环氧乙烷的非离子表面活性剂; 40重量%）和水（60重量%）的系统。小角X射线散射（SAXS）测量表明，双层间距加宽至30 °C，进一步提高温度导致双层更容易波动。Rheo-SALS测量表明C12E4.2粘度增加，并且出现三叶草图案，如先前对于其它CnEm系统所报道的，表明相变。随着剪切速率的增加，囊泡尺寸的减小比非分布系统所报道的要慢。在剪切速率-温度空间中制备的常规动态相图中，出现了相变所需的温度和剪切速率不一致的区域。当施加剪切应力控制流时，相变所需的剪切应力大小随着温度的升高而连续增加。此外，临界剪切应变的剪切速率控制测得的那些相比，得到不同的温度。这些结果表明，双层波动更容易随着温度的升高，需要更多的能量的相转变，所示的应力斜坡测量。因此，温度依赖性双层动力学决定了相变所需的条件，并且相变所需的剪切应力大小也必须在CnEmsystems中考虑。
The effects of temperature and shear conditions on the lamellar-to-multilamellar vesicle (MLV) phase transition were elucidated using rheometry (Rheo)–small-angle light scattering (SALS) measurements for a system comprising C12E4.2(a nonionic surfactant containing distributed ethylene oxide; 40 wt%) and water (60 wt%). Small-angle X-ray scattering (SAXS) measurements indicated that the bilayerd-spacing widened up to 30 °C, and further increasing the temperature caused the bilayer to fluctuate more easily. Rheo–SALS measurements indicated that the C12E4.2viscosity increased, and a cloverleaf pattern appeared, as previously reported for other CnEmsystems, indicating a phase transition. The decrease in vesicle size with increasing shear rate was slower than that reported for the non-distributed system. In a conventional dynamic phase diagram prepared in the shear-rate–temperature space, regions appeared in which temperatures and shear rates required for the phase transition were inconsistent. When a shear-stress-controlled flow was applied, the shear stress magnitude required for the phase transition increased continuously with increasing temperature. Furthermore, critical shear strains comparable to those measured for the shear rate control were obtained for different temperatures. These results suggest that the bilayer fluctuated more easily with increasing temperature, requiring more energy for the phase to transition, as indicated by the stress ramp measurements. Therefore, the temperature-dependent bilayer kinetics determined the conditions required for the phase transition, and shear stress magnitudes required for the phase transition must also be considered in CnEmsystems.
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DOI：
10.1021/acs.langmuir.8b01510
发表时间：
2018
期刊：
Langmuir : the ACS journal of surfaces and colloids
影响因子：
--
作者：
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影响因子：
1.8
作者：
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通讯作者：
C. Oliviero
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影响因子：
3.9
作者：
Florian Nettesheim;J. Zipfel;U. Olsson;F. Renth;Peter Lindner;W. Richtering
通讯作者：
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影响因子：
--
作者：
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通讯作者：
Y. Yamamoto
DOI：
10.1051/jp2:1993211
发表时间：
1993-09-01
期刊：
JOURNAL DE PHYSIQUE II
影响因子：
--
作者：
DIAT, O;ROUX, D;NALLET, F
通讯作者：
NALLET, F