Liquid Crystalline Properties of Symmetric and Asymmetric End-Grafted Cellulose Nanocrystals

The hydrophilic polymer poly[2-(2-(2-methoxy ethoxy)ethoxy)ethylacrylate] (POEG3A) was grafted onto the reducing end-groups (REGs) of cellulose nanocrystal (CNC) allomorphs, and their liquid crystalline properties were investigated. REGs on CNCs extracted from I (CNC-I) are exclusively located at one end crystallite, whereas II (CNC-II) feature both ends so that grafting affords asymmetrically symmetrically decorated CNCs, respectively. To confirm REG modification, several complementary analytical techniques applied. POEG3A CNC evidenced by Fourier transform infrared spectroscopy, atomic force microscopy, coil–globule conformational transition this above 60 °C, i.e., its lower critical solution temperature. Furthermore, we investigated self-assembly end-tethered CNC-hybrids into chiral nematic phases. Above a concentration, end-grafted allomorphs form tactoids. introduction to CNC-I does not disturb surface along rods, allowing modified approach each other helicoidal textures. End-grafted CNC-II formed tactoids with pitch observable polarized optical microscopy. This is likely due increase in hydrodynamic radius or introduced steric stabilization polymer.