Polymethylene with cage silsesquioxane: densely grafted structure prevents side-chain crystallization

Abstract

Cage silsesquioxane (POSS, polyhedral oligomeric silsesquioxane) is a crucial building block in the development of organic–inorganic hybrid polymers. However, polymers incorporating POSS units in their side chains often exhibit poor film-forming properties because of the high crystallinity of POSS. In this study, polymethylene densely grafted with POSS units was synthesized. This POSS-polymethylene structure produced a homogeneous, transparent cast film, in contrast to the turbid film formed by POSS-polyacrylate. The significant difference in the film quality was attributed to the inhibition of POSS crystallization, facilitated by the dense tethering of POSS on the polymethylene backbone.