  Understanding how nanostructure and nanomechanics influence physical material
properties on the micro- and macroscale is an essential goal in soft condensed
matter research. Mechanisms governing fragmentation and chirality inversion of
filamentous colloids are of specific interest because of their critical role in
load-bearing and self-organizing functionalities of soft nanomaterials. Here we
provide a fundamental insight into the self-organization across several length
scales of nanocellulose, an important bio-colloid system with wide-ranging
applications as structural, insulating and functional material. Through a
combined microscopic and statistical analysis of nanocellulose fibrils at the
single particle level, we show how mechanically and chemically induced
fragmentation proceed in this system. Moreover, by studying the bottom-up
self-assembly of fragmented carboxylated cellulose nanofibrils into cholesteric
liquid crystals, we show via direct microscopic observations, that the
chirality is inverted from right-handed at the nanofibril level to left-handed
at the level of the liquid crystal phase. These results improve our fundamental
understanding of nanocellulose and provide an important rationale for their
application in colloidal systems, liquid crystals and nanomaterials.
