Mechanical properties testing of kapok fiber and its SiO2 composite

Natural fiber polymer composites have various potential applications because of its particular property. In this paper, the template technique is employed to prepare SiO2/kapok fiber composite and the mechanical properties of the kapok fibril and its composite are presented. The mechanical tests are carried out on a probe platform which consists of a micro probe with a sharp tip, a micro-force sensor, and a micromanipulator and operates under an optical microscope. The probe platform has a high accurate load and displacement resolutions that are able to meet the requirements of the measurements. During the tests, the probe is controlled by the manipulator to exert lateral force at the midpoint of the kapok fibers which is clamed as a tension spring on a frame. The force is detected by the force sensor and consecutive deformation images of kapok and SiO2/kapok fibers are acquired by the optical microscopic systems. From consistently fitting the measured deformation profiles follows the more accurate calculation model. Thus, the mechanical properties, such as the load-displacement (stress-strain) curve, the elastic modulus of the kapok and SiO2/kapok fibers under different gripping conditions are obtained.