da Silva Perez Denilson, Montanari Suzelei, Vignon Michel R
Centre de Recherches sur les Macromolécules Végétales, (CERMAV-CNRS), Université Joseph Fourier, BP 53, 38041, Grenoble Cedex 9, France.
Biomacromolecules. 2003 Sep-Oct;4(5):1417-25. doi: 10.1021/bm034144s.
Various cellulose samples converted into cellulose III by two different ammonia treatments, either liquid or gaseous, were reacted with catalytic amounts of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO), sodium hypochlorite, and sodium bromide in water. A substantial increase in the reactivity of cellulose III samples was observed in comparison to those in cellulose I, and a relationship between oxidation conditions and cellulose primary hydroxyl groups accessibility was directly established. For the characterization, we have used several methods, mainly (13)C NMR, methylene blue adsorption, FTIR, and conductometric titration. In all samples, the primary alcohol groups were selectively oxidized into carboxyl groups, provided the sodium hypochlorite is added dropwise and the reaction is performed at constant pH 10.
通过两种不同的氨处理（液体或气体）转化为纤维素III的各种纤维素样品，与催化量的2,2,6,6-四甲基哌啶-1-氧基自由基（TEMPO）、次氯酸钠和溴化钠在水中反应。与纤维素I相比，观察到纤维素III样品的反应性有显著提高，并且直接建立了氧化条件与纤维素伯羟基可及性之间的关系。为了进行表征，我们使用了几种方法，主要是（13）C NMR、亚甲基蓝吸附、FTIR和电导滴定。在所有样品中，只要逐滴加入次氯酸钠并在恒定pH值10下进行反应，伯醇基团就会被选择性地氧化成羧基。
