(533d) Enhanced Bondability Of Inorganic Particles With A Cellulosic Substrate By Encapsulation With Regenerated Cellulose

New insights into the solution structure and precipitation behavior of cellulose dissolved in 4-Methylmorpholine N-oxide (NMMO) monohydrate solvent were obtained from rapid precipitation of the cellulose aggregates upon addition of a non-solvent under agitation. Regenerated cellulose nanoparticles were synthesized with controllable morphology, crystalline phase, and crystallinity. Depending on the rate of non-solvent addition, the regenerated cellulose formed wormlike microfibrillar ribbons or spherical nanoparticles with diameters from 20 to 150 nm. Inorganic-cellulose core-shell and hollow cellulose nanoparticles were also prepared by self-encapsulation with regenerated cellulose via precipitation of cellulose in a polyacrylic acid hydrogel layer surrounding nanoparticle templates in NMMO. The cellulose shell surrounding the inorganic surface is composed of ~30 nm cellulose spheres or nodules. It was found that the bondability of the inorganic filler with wood fibers could be significantly improved by coating regenerated cellulose on it, and the degree of this improvement is dependant on the crystallinity, and therefore swellability and conformability of the coating layer.