Effective Young’s Modulus of Bacterial and Microfibrillated Cellulose Fibrils in Fibrous Networks

• DOI: 10.1021/bm300042t
• Publication Date: 2012-03-16T17:10:04Z
• Authors: Supachok Tanpichai; Franck Quero; Masaya Nogi; Hiroyuki Yano; Robert J. Young; Tom Lindström; William W. Sampson; Stephen J. Eichhorn
• Keywords: Micromechanics; Bacterial Cellulose

The deformation micromechanics of bacterial cellulose (BC) and microfibrillated (MFC) networks have been investigated using Raman spectroscopy. spectra both BC MFC exhibit a band initially located at ≈ 1095 cm(-1). We used the intensity this as function rotation angle specimens to study fibril orientation in networks. also change peak's wavenumber position with applied tensile probe stress-transfer behavior these cellulosic materials. did not significantly angle, indicating an in-plane 2D network fibrils uniform random orientation; conversely, highly oriented flax fiber exhibited marked angle. Experimental data theoretical analysis shows that shift rate arising from under tension is dependent on angles between axis fibrils, strain axis, incident laser polarization direction, back scattered configurations. From analysis, effective moduli single were estimated be ranges 79-88 29-36 GPa, respectively. It shown for model fit it necessary use negative Poisson's ratio Discussion "auxetic" given.