Rheological characterization, crystallization, and gelation behavior of monoglyceride gels
Rheological characterization, crystallization, and gelation behavior of monoglyceride gels
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DOI：
10.1006/jcis.2002.8287
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发表时间：
2002-05-15
影响因子：
9.9
通讯作者：
Agterof, WGM
中科院分区：
文献类型：
--
作者：
Sein, A;Verheij, JA;Agterof, WGM
饱和甘油单酯在水中能形成牢固的凝胶。这些凝胶是单酸甘油酯的刚性板状β-晶体的网络（“纸牌屋”），从空间填充的层状液晶相生长。从网络形成的角度讨论了结晶的分子机理。用流变学方法研究了（剪切冷却）单甘酯凝胶的浓度依赖性。已经提出了一种凝胶化机制，包括两个步骤：（i）在形成核之后，在横向方向上发生快速结晶（可能在一个双层内），由此形成第一个空间填充网络。(ii)随后是网络的增强，通过该网络形成结晶双层的堆叠。板状晶体连接在连接域或交界区，可能包含所有的材料（助表面活性剂，甘油二酯等）。不适合水晶阵列的东西小变形流变学表明，高于约2wt%的甘油单酯形成了交联网络。大变形流变学对于在失效时具有相对小的应变（在剪切变形和压缩两者中）的颗粒凝胶是典型的。当对系统施加相对小的变形时，连接域或连接区已经失效。(C)2002年爱思唯尔科学（美国）。
Saturated monoglycerides can form firm gels in water. These gels are networks of stiff plate-like beta-crystals of monoglycerides (a "cardhouse"), grown from a space-filling lamellar liquid-crystalline phase. The molecular mechanism of crystallization is discussed in the light of network formation. The concentration dependence of gel development of (shear-cooled) monoglyceride gels has been studied by theology. A gelation mechanism has been proposed, consisting of two steps: (i) After formation of a nucleus, rapid crystallization in a lateral direction occurs (probably within one bilayer) by which the first space-filling network is formed. (ii) This is followed by reinforcement of the network by which stacks of crystalline bilayers are formed. The plate-like crystals are linked in connective domains or junction zones, probably containing all the material (cosurfactants, diglycerides, etc.) that does not fit in the crystalline array. Small deformation theology shows that above about 2 wt% monoglyceride a percolating network is formed. The large deformation rheology is typical for a particle gel with a relatively small strain at failure (both in shear deformation and compression). The connective domains or junction zones already fail when relatively small deformations are put on the system. (C) 2002 Elsevier Science (USA).