Structure of Sodium Carboxymethyl Cellulose Aqueous Solutions: A SANS and Rheology Study.
Structure of Sodium Carboxymethyl Cellulose Aqueous Solutions: A SANS and Rheology Study.
复制标题
DOI：
10.1002/polb.23657
复制
发表时间：
2015-04-01
期刊：
影响因子：
--
通讯作者：
Cabral JT
中科院分区：
文献类型：
--
作者：
Lopez CG;Rogers SE;Colby RH;Graham P;Cabral JT
报道了取代度为1.2的纤维素衍生物聚电解质羧甲基纤维素钠的小角中子散射和流变学研究。利用SANS，我们确定该聚合物以分子形式溶解在具有拉伸参数的局部刚性构象的水中。我们测定了链的截面半径(3.4o)和关联长度随浓度的标度(ξ=296c−1/2，对于c in g/L)由流变学确定的从半稀到集中交叉保持不变。粘度的测量结果与标度理论的预测是定性一致的，柔性聚电解质呈现半稀疏无纠缠和纠缠状态，然后在高浓度下表现为交叉到中性聚合物浓度的粘度依赖关系。然而，在流变学定义的浓缩区域中，这些较高的浓度仍然在散射函数中显示出峰值，这表明关联长度继续按比例变化。©2014作者。聚合物科学期刊，B部分：聚合物物理，由威利期刊公司出版。科学，B部分：多晶硅。太棒了。2015、53、492-501
We report a small angle neutron scattering (SANS) and rheology study of cellulose derivative polyelectrolyte sodium carboxymethyl cellulose with a degree of substitution of 1.2. Using SANS, we establish that this polymer is molecularly dissolved in water with a locally stiff conformation with a stretching parameter. We determine the cross sectional radius of the chain ( 3.4 Å) and the scaling of the correlation length with concentration (ξ = 296 c−1/2Å for c in g/L) is found to remain unchanged from the semidilute to concentrated crossover as identified by rheology. Viscosity measurements are found to be in qualitative agreement with scaling theory predictions for flexible polyelectrolytes exhibiting semidilute unentangled and entangled regimes, followed by what appears to be a crossover to neutral polymer concentration dependence of viscosity at high concentrations. Yet those higher concentrations, in the concentrated regime defined by rheology, still exhibit a peak in the scattering function that indicates a correlation length that continues to scale as. © 2014 The Authors. Journal of Polymer Science Part B: Polymer Physics Published by Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015, 53, 492–501