Investigation into the structural, morphological, mechanical and thermal behaviour of bacterial cellulose after a two-step purification process
Investigation into the structural, morphological, mechanical and thermal behaviour of bacterial cellulose after a two-step purification process
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DOI：
10.1016/j.biortech.2011.04.077
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发表时间：
2011-10-01
影响因子：
11.4
通讯作者：
Peijs, Ton
中科院分区：
文献类型：
--
作者：
Gea, Saharman;Reynolds, Christopher T.;Peijs, Ton
细菌纤维素（BC）是一种天然水凝胶，由木醋酸杆菌（最近更名为木葡糖醋酸杆菌）在培养中产生，由带状纤维素微纤丝束的三维网络构成。在这里，提出了一种两步纯化方法，该方法显著改善了由静态培养中产生的这些水凝胶加工的BC片材的结构、机械、热和形态学行为。使用2.5 wt.%的一步处理使BC碱化NaOH溶液产生的杨氏模量的两倍增加的处理后的BC片材比未经处理的BC片材。在用2.5重量%的二次处理后实现了进一步的增强。NaOCl（漂白）。这些处理是精心设计的，以防止从纤维素I到纤维素II的任何多晶型晶体转化，这可能对机械性能有害。扫描电子显微镜和热重分析表明，随着化学处理的增加，加工膜的形态和热稳定性也得到改善。(C)2011爱思唯尔有限公司版权所有。
Bacterial cellulose (BC) is a natural hydrogel, which is produced by Acetobacter xylinum (recently renamed Gluconacetobacter xylinum) in culture and constitutes of a three-dimensional network of ribbon-shaped bundles of cellulose microfibrils. Here, a two-step purification process is presented that significantly improves the structural, mechanical, thermal and morphological behaviour of BC sheet processed from these hydrogels produced in static culture. Alkalisation of BC using a single-step treatment of 2.5 wt.% NaOH solution produced a twofold increase in Young's modulus of processed BC sheet over untreated BC sheet. Further enhancements are achieved after a second treatment with 2.5 wt.% NaOCl (bleaching). These treatments were carefully designed in order to prevent any polymorphic crystal transformation from cellulose I to cellulose II, which can be detrimental for the mechanical properties. Scanning electron microscopy and thermogravimetric analysis reveals that with increasing chemical treatment, morphological and thermal stability of the processed films are also improved. (C) 2011 Elsevier Ltd. All rights reserved.