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炭甲基氧甲基 guar gum 在稀释水性介质中的物理化学特性

Emmanuel M Nsengiyumva¹, Mark P Heitz², Paschalis Alexandridis³

¹Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York (SUNY), Buffalo, NY 14260-4200, USA; Department of Chemistry and Biochemistry, The State University of New York (SUNY) Brockport, Brockport, NY 14420, USA.

International journal of biological macromolecules

|February 29, 2024

概括

碳氧甲基基 (CMHPG) 在盐溶液中由于选的电荷而降低粘度,导致更紧的结构. 这种耐盐聚合物表现出比原生瓜尔更好的性能.

科学领域:

聚合物科学聚合物科学
解决方案化学解决方案化学
材料科学材料科学材料科学

背景情况:

瓜尔衍生物被广泛用作加厚剂.
了解在离子环境中修改的瓜尔的溶液行为对于优化它们的应用至关重要.

研究的目的:

为了研究含有不同盐度 (NaCl,KCl,CaCl2) 的水溶液中的碳氧甲基基 (CMHPG) 的溶液特性.
为了确定CMHPG在不同离子强度下的内在粘度和结构变化.
为了比较CMHPG的盐分耐受性和风湿性行为与原生瓜尔和桑坦.

主要方法:

在水和盐溶液中测量CMHPG溶液的粘度.
将实验数据与Huggins,Kraemer和Rao模型相匹配,以计算内在粘度 ([η]).
确定水力动力学线圈半径 (Rcoil) 和粘性流动的激活能量.

主要成果:

劳的模型提供了最适合粘度数据的模型 (R2 = 0.779-0.999).
[η]随着盐度 (0.9-100 mM) 的增加而显著下降 (高达84%),表明了聚合物链的紧缩.
在降低粘度和线圈半径方面,KCl和CaCl2比NaCl更有效.
与原生瓜尔相比,CMHPG表现出盐耐受性,粘度变化较小.

结论:

盐离子有效地屏蔽CMHPG的带电侧组,从而导致更紧的聚合物结构和减少溶液粘度.
与原生瓜尔相比,CMHPG表现出优越的盐耐受性.
对于CMHPG粘性流的激活能量高于丹的激活能量.

关键词:

配方配方配方是一个瓜尔瓜尔的口香糖是什么意思聚电解质的多电解质它是一种多糖化合物.粘度粘度粘度粘度粘度

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