Grafting liquid crystalline polymers from cellulose substrates using atom transfer radical polymerization

Immobilizing liquid crystalline polymers on cellulose generates new possibilities of accomplishing addressable/responsive bio-based substrates. In this paper we report on our first steps to combine the electro-optic properties of liquid crystals with the versatility of paper as a displaying substrate. Electric current or magnetic fields can be used to manipulate the orientation of liquid crystals and thereby change the appearance and the properties of the material. Atom transfer radical polymerization (ATRP) can be used successfully to graft polymers from solid substrates in a controlled manner. In this study it is shown that the grafting of a liquid crystalline monomer, 11-(4-cyanophenyl-4-phenoxy)undecyl acrylate, onto cellulose by ATRP is possible, and that thicker films can be obtained by using PMA as a spacer in between the cellulose and the liquid crystalline block. The cellulose fibers become highly hydrophobic subsequent to grafting and the liquid crystalline polymer possesses mesophases accessible for further processing.