Clarification of GO acted as a barrier against the crack propagation of the cellulose composite films

Graphene oxide, flat carbon nanosheets, has generated extensive interests in many areas of science and engineering due to its unprecedented physical and chemical properties. With the development of wide-scale applicability including facile synthesis and high yield, this exciting material is ready for practical applications. In this work, fully exfoliated graphene oxide nanosheets were introduced into cellulose matrix through a facial pathway. A significant increase in the elongation at break of the composites was observed; that was, a 120% improvement in the tensile strength and a nearly 3 times increase in elongation at break were achieved for the composite films with GO content of 0.27 vol%. The microstructures of the regenerated cellulose films before and after loading of GO nanosheets were characterized by using SEM and TEM. Furthermore, the theoretical simulation from Young's modulus of the composite films indicated that the GO nanosheets had unidirectional arrangement tendency rather than random dispersion in cellulose matrix, which contributed to the improvement in the elongation of the composites, which was supported by the SEM results of the cross-section of the broken composite. (C) 2014 Elsevier Ltd. All rights reserved.