...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Holzforschung >A CP/MAS ~(13)C-NMR study of cellulose fibril aggregation in eucalyptus dissolving pulps during drying and the correlation between aggregate dimensions and chemical reactivity
【24h】

A CP/MAS ~(13)C-NMR study of cellulose fibril aggregation in eucalyptus dissolving pulps during drying and the correlation between aggregate dimensions and chemical reactivity

机译：CP / MAS〜（13）C-NMR研究纤维素溶解过程中纤维素原纤维在干燥过程中的聚集以及聚集体尺寸与化学反应性之间的关系

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Changes in supramolecular properties of cellulose I, namely its lateral fibril aggregate dimension (LFAD), in bleached hardwood acid bisulphite pulp during drying was studied using cross-polarization/magic angle spinning carbon-13 nuclear magnetic resonance (CP/MAS ~(13)C-NMR) in combination with spectral fitting. A significant change in aggregate dimensions was noticed when each of the pulp grades were oven dried. The effect of drying was further investigated with pulp samples subjected to different drying methods. A comparison of a harsh oven drying, mild and rapid air drying, and a very mild and slow condition drying showed that the LFAD of the material decreases in the following order: oven drying > air drying > condition drying. The correlation between the total extractable material S_(10) (%) and LFAD and also the LFAD increment (ΔLFAD in %) are presented and shown to be intimately related. This means that the method of drying influences the size of the fibril aggregate dimensions and depends on the presence of extractable material within the fibre cell wall. Reactivity studies were carried out based on the acetylation of cotton linters and commercial 96a pulp. Results indicate that the initial reaction rate is proportional to the specific surface area of the two cellulose pulp samples. Accordingly, the specific surface area is directly related to initial reactivity of the performed acetylation. We demonstrated that it is possible to control the LFAD and hence specific surface area in laboratory-produced pulps 91α, 92α, and 96α by the drying method. Thus controlling LFAD can probably be one viable route for controlling the initial reactivity of dissolving pulp towards acetylation.
机译：使用交叉极化/魔角旋转碳13核磁共振（CP / MAS〜（13）研究了漂白的硬木酸亚硫酸氢盐浆在干燥过程中纤维素I的超分子性质，即其横向原纤维聚集体尺寸（LFAD）的变化。 C-NMR）与光谱拟合相结合。当每种纸浆等级进行烘箱干燥时，会发现骨料尺寸发生了显着变化。对于采用不同干燥方法的纸浆样品，进一步研究了干燥效果。严格的烤箱干燥，温和快速的空气干燥以及非常温和的缓慢状态干燥的比较显示，材料的LFAD按以下顺序降低：烤箱干燥>空气干燥>条件干燥。提出了总可提取材料S_（10）（％）和LFAD之间的相关性，并且还显示了LFAD增量（以％为单位的ΔLFAD）之间的相关性，并显示为密切相关。这意味着干燥方法会影响原纤维聚集体尺寸的大小，并取决于纤维细胞壁中可提取物质的存在。反应性的研究是基于棉短绒和商品96a纸浆的乙酰化进行的。结果表明，初始反应速率与两个纤维素纸浆样品的比表面积成正比。因此，比表面积与进行的乙酰化的初始反应性直接相关。我们证明了通过干燥方法可以控制实验室生产的纸浆91α，92α和96α中的LFAD，从而控制其比表面积。因此，控制LFAD可能是控制溶解纸浆对乙酰化的初始反应性的一条可行途径。

著录项

  • 来源
    《Holzforschung》 |2010年第6期|p.693-698|共6页
  • 作者

    Viren Chunilall; Tamara Bush; Per Tomas Larsson; Tommy Iversen; Andrew Kindness;

  • 作者单位

    Council for Scientific and Industrial Research, Forestry and Forest Products Research Centre (CSIR-FFP), P.O. Box 17001, Congella, Durban, 4013, South Africa University of Kwa-Zulu Natal, Westville, Durban, South Africa;

    rnCouncil for Scientific and Industrial Research, Forestry and Forest Products Research Centre (CSIR-FFP), Congella, Durban, South Africa University of Kwa-Zulu Natal, Westville, Durban, South Africa;

    rnInnventia, AB, Stockholm, Sweden;

    rnInnventia, AB, Stockholm, Sweden;

    rnUniversity of Kwa-Zulu Natal, Westville, Durban, South Africa;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

    acetylation; air drying; condition drying; lateral fibril aggregate dimensions (LFAD); oven drying; reactivity of cellulose;

    机译：乙酰化风干条件干燥;横向原纤维骨料尺寸（LFAD）;烤箱干燥;纤维素的反应性;

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号