Friction Coefficient of Well-Defined Hydrogel Networks
Friction Coefficient of Well-Defined Hydrogel Networks
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DOI：
10.1021/acs.macromol.5b01997
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发表时间：
2016-01
期刊：
影响因子：
5.5
通讯作者：
Midori Fujiki;Masaya Ito;K. Mortensen;Shintaro Yashima;M. Tokita;M. Annaka
中科院分区：
文献类型：
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作者：
Midori Fujiki;Masaya Ito;K. Mortensen;Shintaro Yashima;M. Tokita;M. Annaka
用简单设计的装置测定了Tetronic凝胶与水之间的摩擦系数随凝胶中聚合物浓度和温度的变化。通过活化酯化学交联Tetronic大分子单体制备Tetronic凝胶。预期凝胶具有均匀的网络结构。摩擦系数f与聚合物浓度Cp的关系可用指数v = 1.5的幂律关系f <$Cpν来表示，这与标度理论的预测相一致.由水的粘度归一化的摩擦系数f（T）/η（T）随温度而增加。当网络是均匀的时，网孔尺寸由最近的聚合物-聚合物接触之间的平均距离给出。因此，f（T）/η（T）比值随温度的升高是由于链在较高温度下脱水而导致网络的平均网眼尺寸减小。随机交叉的摩擦系数。
The friction coefficient between Tetronic gel and water is measured as a function of the polymer concentration of the gel and the temperature by a simply designed apparatus. Tetronic gel was prepared by cross-linking Tetronic macromonomers through activated ester chemistry. The gel is expected to have homogeneous network structure. The polymer concentration Cp dependence of the friction coefficient f is well expressed by a power law relationship f ∼ Cpν with the exponent of ν = 1.5, which is in a good agreement with the prediction of the scaling theory. The friction coefficient normalized by viscosity of water, f(T)/η(T), increases with temperature. When the network is homogeneous, the mesh size is given by the average distance between the nearest polymer–polymer contacts. Therefore, the increase in the ratio f(T)/η(T) with temperature attributed to the decrease in the average mesh size of the network due to the dehydration of the chains at higher temperature. The friction coefficient for randomly cross-l...