Performances and decision framework of CNT-infused bio-based hybrid composites for lightweight smart structures

Development of lightweight structures with sustainable materials created a suitable substitute to non-renewable traditional materials due to its cost-effective, abundant availability, biodegradability, and reduced carbon emissions. However, moderate strength-stiffness and toughness of these biobased composites are not predominant for load bearing structural applications. Thus, inclusion of CNTs nanoparticles played a vital role that not only improved fracture resistance but also increased the interfacial properties with greater strength and stiffness. This study projected to develop lightweighted sustainable hybrid structures by infusing CNTs at nano level (0-6%) with banana-pineapple laminated fibers at different stacking arrangements. XRD and FTIR characteristics of CNTs showed better crystallinity with uniform dispersion and stretching mechanisms. TEM and FESEM analysis showed that CNTs nanoparticles are spherical in shape with a magnified surface interfacial area that greatly adhesive with epoxy matrix. The results analyzed that 3% CNTs infused BPBP and BBPP hybrid composites showed maximum tensile strength (229.94 MPa), flexural strength (190.78 MPa), interfacial shear strength (41.51 MPa), impact strength (52.39 kJ/m²), and energy absorbing (9.95 J) properties which is higher tensile strength (36.2% & 75.4%), flexural strength (39.3% & 120%), shear strength (125% & 380%), impact strength (59.5% & 113%), and energy absorbing (41.2% & 84.6%) as compared to non-hybrid composites (BBBB & PPPP) respectively. The C-scan images, ultrasonic wave patterns, and morphology analysis also revealed that 3% CNTs infused epoxy matrix are dispersed homogeneously between the fiber layers that controlled the damages and delamination during higher penetration and impact load. Finally, in order to choose the best configuration among the prepared hybrid composite structures, a novel fuzzy strategy based on Schweizer-Sklar techniques was also executed.