Experimental investigation of the structural and thermal properties of ramie fiber composites using the response surface methods

Abstract This research explored the potential of ramie fibers (RFs) as a natural reinforcement in polymer composites. Composites were prepared with RF content varying between 20 and 60% by weight. The physical, mechanical, and thermal performance characteristics of these composites have been thoroughly investigated. Furthermore, microscopic analysis was used to assess the interactions at the fiber–matrix interface, and the impact of fiber ratio on the composites’ overall performance was examined. The increase in the RF ratio within the composite structure led to a rise in both water absorption and porosity values. There was also a decrease in ultrasonic pulse velocity (UPV), density, compressive strength, and thermal conductivity. Analysis of the microstructure revealed that the increase in the RF ratio caused incompatibilities at the fiber–matrix interfaces. The mechanical qualities suffered as a result of this. The best thermal conductivity was 0.0931 W m −1 K −1 in the %60 RF composite sample. Although high RF concentration reduces compressive strength, the results show that composites have the potential to be used as insulation materials by improving thermal insulation performance. However, samples containing 25 and 30% RF have proven to be a reasonable choice for applications that need to balance low density, good insulation properties, and mechanical performance. In the models prepared using response surface methodology (RSM), the statistical analysis results were found to be significant, and their high R 2 values indicate a high explanatory power of the model.