Effect of Ramie Fabric Chemical Treatments on the Physical Properties of Thermoset Polylactic Acid (PLA) Composites

Abstract

Ramie fabric-reinforced thermoset polylactic acid (PLA) composites were prepared by using heat pressing technology. Fabrics were treated with alkali, silane, and alkali–silane respectively, expecting an improvement of the interface between the fabric and the matrix. Scanning electron microscopy (SEM) results indicated that after alkali treatment, impurities on the fiber surface were removed and its diameter became finer. After the silane, and alkali–silane treatments, the contact angles of the ramie fibers increased by 14.26%, and 33.12%, respectively. The contact angle of the alkali–silane treated fiber reached 76.41°; this is beneficial for the adhesion between ramie fiber and the PLA. The research revealed that the tensile strength of the fiber increased after the alkali and silane treatments. A slight decrease was noticed on the tensile strength of fibers treated with alkali–silane. After all, three chemical treatments were done, the flexure strength of the ramie fabric-reinforced PLA composites, improved in all cases. Among the three treatments, the alkali–silane treatment demonstrated the best result, as far as the flexure strength and modulus of the fabricated composites were concerned. On the other hand, water absorption of the related composites decreased by 23.70%, which might contribute to the closer contact between the ramie fiber and the matrix. The ramie fabric-reinforced PLA composites, prepared in this study, can meet the standard requirements of aircraft interior structures and have favorable application foreground.

Physical and abrasive wear behaviour of Urena lobata fiber-reinforced polymer composites

“…This can be attributed to the fact that alkaline treatment causes roughness of the surface of the fibers, which in turn creates more avenues for more water absorption. 40,41…”

“…This can be attributed to the fact that alkaline treatment causes roughness of the surface of the fibers, which in turn creates more avenues for more water absorption. 40,41 The diffusion coefficients of Urena lobata fiberreinforced PP composites may be compared with those of the other natural fiber-reinforced composite materials with varying fiber loadings as presented in Table 4. It is shown that the values of diffusion coefficient of Urena lobata fiber-reinforced PP composites are in the order of 10 �5 -10 �7 mm 2 /s or 10 �11 -10 �13 m 2 /s for natural fiber-reinforced polymer composites.…”

Towards a Circular Economy in the Aviation Sector Using Eco-Composites for Interior and Secondary Structures. Results and Recommendations from the EU/China Project ECO-COMPASS

“…It is demonstrated that not only the fracture toughness, interfacial shear strength, tensile strength and modulus are improved by the component hybridization, nanoparticle grafting and nano-modification, but also the fire retardation and the anti-microbial performances. Moreover, the unique hollow structure of the plant fibers can provide additional benefit in structural damping, noise reduction and heat isolation compared to traditional glass or carbon fiber counterparts, behavior that is exactly desired for an aircraft interior structure [5][6][7][8]. Additionally, in the improvement of pure natural fiber reinforced polymer properties, the utilization of valuable recycled carbon fibers (rCF) as alternatives to enhancing the properties of eco-composites has been considered.…”

Special Issue “ECO-COMPASS: Ecological and Multifunctional Composites for Application in Aircraft Interior and Secondary Structures”

“…The numerical results highlight the prospect of conductive CNT networks to be used as a localized structural health monitoring technique in carbon fibre reinforced polymers (CFRP) and bio-composites. Wang et al [6] studied the effect of ramie fabric chemical treatments on the physical properties of thermoset polylactic acid (PLA) composites. It was found that chemical treatments lead to an increase in tensile and flexural strength of PLA composites while they lead to a decrease in water absorption.…”