An estimation of the Young's modulus of bacterial cellulose filaments
An estimation of the Young's modulus of bacterial cellulose filaments
复制标题
DOI：
10.1007/s10570-008-9206-8
复制
发表时间：
2008-08-01
期刊：
影响因子：
5.7
通讯作者：
Eichhorn, S. J.
中科院分区：
文献类型：
--
作者：
Hsieh, Y. -C.;Yano, H.;Eichhorn, S. J.
估计，使用拉曼光谱技术，细菌纤维素的单丝的杨氏模量。该技术用于通过1095 cm（-1）拉曼谱带的中心位置的位移来确定细菌纤维素的局部分子变形，这对应于纤维素结构骨架中糖苷键的拉伸。通过计算相对于所施加的应变的移位率，可以估计细菌纤维素的单个原纤维的刚度。为了进行这种估计，将纤维网络旋转360度，并记录1095 cm（-1）拉曼带的强度。结果表明，该带的强度在很大程度上与旋转角度无关，这表明网络是随机分布的。使用先前公布的数据，从拉曼谱带位移对模量的校准预测模量，并通过使用Krenchel分析来反算单个原纤维的模量。所获得的值（114 GPa）高于先前报道的该参数的值，但低于纤维素-I的晶体模量的估计值（130-145 GPa）。这些差异的原因给出的结晶度和样品的结构组成。
An estimation, using a Raman spectroscopic technique, of the Young's modulus of a single filament of bacterial cellulose is presented. This technique is used to determine the local molecular deformation of the bacterial cellulose via a shift in the central position of the 1095 cm(-1) Raman band, which corresponds to the stretching of the glycosidic bond in the backbone of the cellulose structure. By calculating the shift rate with respect to the applied strain it is shown that the stiffness of a single fibril of bacterial cellulose can be estimated. In order to perform this estimation, networks of fibres are rotated through 360 degrees and the intensity of the 1095 cm(-1) Raman band is recorded. It is shown that the intensity of this band is largely independent of the angle of rotation, which suggests that the networks are randomly distributed. The modulus is predicted from a calibration of Raman band shift against modulus, using previously published data, and by using Krenchel analysis to back-calculate the modulus of a single fibril. The value obtained (114 GPa) is higher than previously reported values for this parameter, but lower than estimates of the crystal modulus of cellulose-I (130-145 GPa). Reasons for these discrepancies are given in terms of the crystallinity and structural composition of the samples.