Bamboo cellulose fibers prepared by different drying methods: Structure-property relationships

Abstract

Bamboo cellulose fibers (BCFs) has attracted increasing attention in many fields due to its high mechanical strength and interconnected porous structure. Drying is a key factor that determines the final structure and properties of BCFs. In this work, three kinds of BCFs, i.e., conventional-dried (CD-BCFs), freeze-dried (FD-BCFs), and supercritical CO₂-dried (SD-BCFs), were prepared via different drying methods. The effects of drying methods on their supramolecular structure, porosity, and mechanical properties were studied, and the structure-property relationships were proposed. The CD-BCFs composed of well-aligned crystalline nanofibrils with a dense structure exhibited the best mechanical properties (tensile strength of 854.54 MPa). The SD-BCFs featured with interconnected 3D microfibril networks give a highly porous structure and the highest surface area of 9.162 m²/g. The FD-BCFs showed medium mechanical properties and surface area owing to the stacked lamellar microfibril network. This work provides guidelines for designing BCFs with proper structure for various end-use applications.

Keywords: Bamboo cellulose fiber; Drying methods; Porous structure; Supramolecular structure; Tensile strength.