Complexes of starch polysaccharides and poly (ethylene co-acrylic acid) : structure and stability in solution
Complexes of starch polysaccharides and poly (ethylene co-acrylic acid) : structure and stability in solution
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淀粉多糖和聚（乙烯共丙烯酸）复合物：结构和溶液稳定性
DOI：
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发表时间：
1991
期刊：
影响因子：
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通讯作者：
Y. Wu
中科院分区：
文献类型：
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作者：
R. Shogren;R. Greene;Y. Wu
摘要：本文采用Chiroptical方法研究了直链淀粉和支链淀粉在水溶液中与聚乙烯共丙烯酸（EAA）的构象和相互作用。这些研究以及x射线衍射和固体核磁共振数据表明，直链淀粉和EAA，以及支链淀粉和EAA在水悬浮液中混合时形成螺旋V型包合物。这种结构显然解释了在含有淀粉和EAA的薄膜中观察到的部分相容性。重量约为1的EAA不与直链淀粉相互作用，可能代表EAA胶束的富含乙烯的中心核心。EAA/直链淀粉配合物在10 mM NaOH溶液中的温度在0 ~ 90℃下稳定，而EAA/直链淀粉配合物在相同溶剂中的温度在此温度下大部分被破坏。尿素浓度为8 M时，进一步破坏了EAAIamylopectin和EAAIamylose复合物的稳定性。碱性pH值（bbb9.5）的溶液能最大限度地分散EAA，并能最大限度地与直链淀粉络合。在pH值为> - 13时，EAAI直链淀粉配合物较弱，这很可能是由于直链淀粉的离子化羟基与EAA的羧基之间存在静电斥力。
SYNOPSIS Chiroptical methods have been used to study the conformation and interactions of amylose and amylopectin with poly (ethylene co-acrylic acid) (EAA) in aqueous solution. These studies, along with X-ray diffraction and solid-state NMR data, show that amylose and EAA, as well as amylopectin and EAA, form helical V -type inclusion complexes when mixed in aqueous suspension. This structure apparently accounts for the partial compat ibility observed in films containing starch and EAA. About i by weight of EAA does not interact with amylose and probably represents the ethylene-rich central core of the EAA micelle. EAA/amylose complexes in 10 mM NaOH were stable to temperatures> 90°C, whereas EAAIamylopectin complexes in the same solvent were largely disrupted at this temperature. Urea, at a concentration of 8 M, further destabilized both EAAIamylopectin and EAAIamylose complexes. Solutions with an alkaline pH (> 9.5) dispersed EAA op timally and allowed maximum complexing with amylose. At pH values> 13, the EAAI amylose complexes were weaker, most likely due to electrostatic repulsion between ionized hydroxyl groups of amylose and carboxyl groups of EAA.