Characterizing Cryptostegia grandiflora stem fiber for reinforcing lightweight polymer composites: A comprehensive study of its physical, chemical, and thermal properties

This study aimed to characterize Cryptostegia grandiflora stem fiber (CGSF) as a potential reinforcement material for lightweight polymer composites. Natural fiber-reinforced materials have gained attention as a promising alternative to synthetic fibers due to their comparable strength and modulus, and lack of harmful chemicals. The physical, chemical, and thermal properties of CGSF were investigated through fiber roughness, chemical measurement, physical measurement, Fourier transform infrared spectroscopy, XRD, water absorption, thermogravimetric analysis, and SEM conformation analysis. The results showed that CGSF has a high cellulose content (80.3 wt.%) and specific strength, making it suitable for use in polymer composites. Its flaky layered outer surface provides a high modulus, and its low microfibril angle observed through electron microscopy results in strong bonding qualities. The fiber also demonstrated improved heat stability up to 254–387 °C through thermogravimetric analysis, meeting the requirements for polymerization. These findings demonstrate the potential of CGSF as a natural reinforcement material for lightweight polymer composites.