Abstract
Thanks to good mechanical performances, high availability, low cost and low weight, the agave sisalana fiber allows to obtain biocomposites characterised by high specific properties, potentially very attractive for the replacement of synthetic materials in various industrial fields. Unfortunately, due to the low strength versus transversal damage processes mainly related to the matrix brittleness and/or to the low fiber/matrix adhesion, the tensile performance of random short fiber biocomposites are quite low, and to date most of the fiber treatments proposed in literature to improve the fiber-matrix adhesion, have not led to very satisfactory results. In order to overcome such a drawback, this work in turn proposes the proper introduction of low fractions carbon nanotubes to activate advantageous improvements in matrix toughness as well as fiber-matrix bridging effects, that can both lead to appreciable increments of the tensile strength.Systematic experimental static and fatigue tests performed on high quality biocomposites obtained by an optimized compression molding process, have shown that the introduction of 1% of carbon nanotubes is sufficient to gives significant improvement in both stiffness and static tensile strength, respectively by approximately 28% and 30%. Furthermore, toughening the biocomposite with 1% of nanotubes results in an appreciable enhancement in lifetime of at least 3 orders of magnitude. Biocomposites with 2% of CNTs show instead more limited improvement of 13% in stiffness, 6% in strength and 150% in lifetime. Also, a thorough analysis of the damage processes by SEM micrographs, as well as of the main fatigue data, has allowed to determine the model that can be used to predict the fatigue performance of such biocomposites.
Highlights
The use of composite materials reinforced by natural fibers is growing strongly in many industrial fields, in the automotive sector [1,2,3], and in the civil construction area and in the naval field
Since the scientific literature [29,30,31,32,33,34,35,36,37,38,39,40] shows that the incorporation of singlewalled and multi-walled carbon nanotubes in traditional fiber-reinforced polymers (FRPs) can significantly increase their static strength and the fatigue life, it seems reasonable to theorise that the dispersion of Carbon Nanotubes (CNTs) in the matrices could lead to significant improvements in the mechanical performance of biocomposites, especially under fatigue loading
In more detail, passing from the biocomposite CNT0% to the biocomposites with CNT1% the amount of the damaging corresponding to the first two phase decreases whereas the pull-out amount increase; both phenomena justify the increasing of the energy to failure of about 20%
Summary
The use of composite materials reinforced by natural fibers is growing strongly in many industrial fields, in the automotive sector [1,2,3], and in the civil construction area and in the naval field. Since the scientific literature [29,30,31,32,33,34,35,36,37,38,39,40] shows that the incorporation of singlewalled and multi-walled carbon nanotubes in traditional fiber-reinforced polymers (FRPs) can significantly increase their static strength and the fatigue life, it seems reasonable to theorise that the dispersion of CNTs in the matrices could lead to significant improvements in the mechanical performance of biocomposites, especially under fatigue loading This is a very important goal, considering that the improving of the fatigue performance of FRPs is currently an important research objective for both scientific community and industry. The fibers were cut with an optimal length of 5 ± 2 mm
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.