Single step PAA delignification of wood chips for high-performance holocellulose fibers

Abstract

Holocellulose fibers produced by mild delignification form strong fiber networks, without beating or dry-strength agents. Recently, sequential batch delignification using peracetic acid (PAA) on finely cut wood sticks resulted in high-quality holocellulose fibers. Here, single step PAA delignification is developed for wood chips, which is simpler and can be used for larger fiber batches (400 g) with similar, high yield (60%). Such fibers have 1.4% lignin, 25% hemicelluloses content and well-preserved cellulose and hemicellulose molar mass. The corresponding paper sheet materials with a porosity of ~ 50%, have a Young’s modulus of 9 GPa and a strength of 90 MPa. Holocellulose fibers can now be readily investigated for use in larger scale paper, molded fiber and polymer biocomposite materials applications, or for cellulose nanofibril preparation.