Accelerated ultraviolet aging behavior and numerical simulation of ramie/carbon fiber reinforced polyethylene terephthalate glycol hybrid composites

Multi-fibers reinforced polymer hybrid composites can be designed to achieve excellent comprehensive performance through maximizing fibers physical and chemical properties. The accelerated ultraviolet (UV) aging behavior and mechanical degradation of natural ramie fiber (R) and carbon fiber (C) reinforced polyethylene terephthalate glycol (PETG) hybrid composites were investigated to broaden the industrial applications and understand the performance of ramie plant fiber products. The results show that the color and thermal properties of PETG matrix after UV aging have changed. The flexural properties of R/C laminated composites vary with the material types and layup sequences. The flexural modulus of the unaged [C/R/C/R]s and [C/C/R/R]s composites increase 1.2 and 1.0 times as compared with the unaged [R/C/R/C]s and [R/R/C/C]s. After 28 days of UV aging, the flexural strength retention rates of the [R/R/R/R]s, [R/R/C/C]s, [R/C/R/C]s, [C/R/C/R]s, [C/C/R/R]s and [C/C/C/C]s composites were 77.1 %, 79.2 %, 78.8 %, 81.7 %, 83 % and 87.4 %, respectively. The fracture strains of the R/C composites increase significantly after UV aging. The multiscale finite element model of the R/C composites is established to study the UV aging mechanism and predict the mechanical degradation. The knowledge gained in this work will be beneficial for the design and engineering application of plant fiber reinforced polymer hybrid composite materials.