Mechanical Properties of the Fiber Cell Wall in Bambusa pervariabilis Bamboo and Analyses of Their Influencing Factors

The cell wall mechanical properties are an important indicator for evaluating the overall mechanical properties of natural bamboo fibers. Using the nanoindentation technique, the variation of the mechanical properties of the fiber cell wall of Bambusa pervariabilis culms with different ages and different positions (both radial and longitudinal) was studied. Moreover, x-ray diffraction (XRD) was employed to measure the microfibril angle (MFA), and the correlation between the MFA and the mechanical properties of the fiber cell wall. The results showed that there was a remarkable difference in the fiber cell wall mechanical properties at different ages and at different radial and longitudinal positions. However, at different ages and at different positions, the absolute value of variation of MFA was less than 1 degrees and was very minor. Furthermore, there was no significant correlation between the fiber cell wall mechanics and MFA, indicating that the mechanical property of the fiber cell walls might be synergistically affected by many factors.