Structure and dynamics of networks in mixtures of hydrophobically modified telechelic multiarm polymers and oil in water microemulsions.
Structure and dynamics of networks in mixtures of hydrophobically modified telechelic multiarm polymers and oil in water microemulsions.
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疏水改性遥爪多臂聚合物和水包油微乳液混合物中网络的结构和动力学
DOI：
10.1021/la303673a
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
M. Gradzielski
中科院分区：
文献类型：
--
作者：
P. Malo de Molina;C. Herfurth;A. Laschewsky;M. Gradzielski
研究了不同官能度的遥爪聚合物改性的水包油（O/W）微乳液（ME）的结构和动力学性质，通过动态光散射（DLS）、小角中子散射（SANS）和高频流变学测量研究疏水改性臂的数目f）作为聚合物结构和添加的聚合物的量的函数。为此目的，我们采用了通过可逆加成-断裂链转移方法合成的量身定制的疏水封端聚（N，N-二甲基丙烯酰胺）星星聚合物，其具有可变数量的封端f，具有不同的烷基链长度。不同的封端聚合物的添加到不带电的ME的O/W液滴导致系统的粘度的大的增强。SANS实验表明，O/W ME液滴不改变后，添加的聚合物，它的存在只改变interdroplet的相互作用。粘度在加入聚合物后大大增加，并且这种增强明显取决于疏水粘着剂的烷基长度，因为它控制在ME液滴中的停留时间。类似地，高频模量G 0取决于添加的聚合物的量，但不取决于粘贴长度。随着f的增加，网络形成的开始转移到每个ME液滴的粘着物数量较少，并且网络形成变得更加有效。因此，网络形成的动力学由聚合物结构控制。DLS看到的动态效果甚至更加明显。在增加聚合物浓度时，出现较慢的弛豫模式，随着臂数的增加变得特别明显。松弛动力学与流变松弛相关，并且两者都由聚合物结构控制。
The structural and dynamical properties of oil-in-water (O/W) microemulsions (MEs) modified with telechelic polymers of different functionality (e.g., number of hydrophobically modified arms,f) were studied by means of dynamic light scattering (DLS), small-angle neutron scattering (SANS), and high frequency rheology measurements as a function of the polymer architecture and the amount of added polymer. For this purpose, we employed tailor-made hydrophobically end-capped poly(N,N-dimethylacrylamide) star polymers of a variable number of endcaps,f, of different alkyl chain lengths, synthesized by the reversible addition–fragmentation chain transfer method. The addition of the different end-capped polymers to an uncharged ME of O/W droplets leads to a large enhancement of the viscosity of the systems. SANS experiments show that the O/W ME droplets are not changed upon the addition of the polymer, and its presence only changes the interdroplet interactions. The viscosity increases largely upon addition of a polymer, and this enhancement depends pronouncedly on the alkyl length of the hydrophobic sticker as it controls the residence time in a ME droplet. Similarly, the high frequency modulusG0depends on the amount of added polymer but not on the sticker length.G0was found to be directly proportional tof– 1. The onset of network formation is shifted to a lower number of stickers per ME droplet with increasingf, and the network formation becomes more effective. Thus, the dynamics of network formation are controlled by the polymer architecture. The effect on the dynamics seen by DLS is even more pronounced. Upon increasing the polymer concentration, slower relaxation modes appear that become especially pronounced with increasing number of arms. The relaxation dynamics are correlated to the rheological relaxation, and both are controlled by the polymer architecture.
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低官能度遥爪星形嵌段共聚物的相行为。
影响因子：
3.4
作者：
F. Lo Verso;A. Panagiotopoulos;C. N. Likos
通讯作者：
C. N. Likos
聚合物微乳液网络的免疫性
DOI：
10.1140/epje/e2006-00010-y
发表时间：
2005
期刊：
The European Physical Journal E
影响因子：
--
作者：
G. Hed;S. Safran
通讯作者：
S. Safran
通过动态光散射探测粘弹性流体的动力学行为的双流体模型分析。
DOI：
10.1021/la035678h
发表时间：
2004
期刊：
Langmuir : the ACS journal of surfaces and colloids
影响因子：
--
作者：
E. Michel;G. Porte;L. Cipelletti;J. Appell
通讯作者：
J. Appell
通过光子相关光谱和小角 X 射线散射研究物理交联非离子微乳液的弛豫现象和结构发展
影响因子：
4.4
作者：
M. Schwab;B. Stühn
通讯作者：
B. Stühn
聚合物-微乳液相互作用：凝聚模型
影响因子：
8.6
作者：
D. Siano;J. Bock
通讯作者：
J. Bock