Green process for fibrous networks extraction from Opuntia (Cactaceae): Morphological design, thermal and mechanical studies.

Highlights • A green process was used to manually extract fibrous networks from the cactus plant. • Fibrous layers have a natural net-like structure with a low bulk density. • Fibrous networks have good thermal stability and suitable mechanical properties. Abstract The present study focuses on the extraction and characterization of natural cellulosic tissues from the cactus Opuntia ficus-indica. A major goal is the establishment of a "green" process for fibrous networks extraction that allows for biomass valorization using sustainable plant fibers. This process shall contribute to the eco-friendly concept. Numerous separated fibrous layers (tissues) with intricate structures were obtained from different parts of the plant. Bulk density and thicknesses of the fibrous layers were determined including evaluation of fiber swelling (water uptake test) and detailed arrangement of the fibrous layers according to thickness was given. A good layer distribution and different values of bulk density were obtained for the studied tissues. The macrostructure (topology and geometric parameters) and microstructure (internal and anatomical structures) of fibrous networks were studied using both bright-field microscopy and scanning electron microscopy. A high diversity of fibers having a complex hierarchical structure was observed. The study of the fibrous-networks crystallinity and the thermostability indicate that water-immersion processing ameliorated the thermal stability in some temperature regions. The fibrous networks mechanical studies were examined, and the results showed a good response strength, especially for uniaxial tensile layers, which has led to the highest strength and elastic modulus. [ABSTRACT FROM AUTHOR]