Phase separation approach to a reactive polycarbonate monolith for "click" modifications

A new polycarbonate monolith carrying allyl groups has been introduced. The monolith was fabricated via the phase separation induced by adding cyclohexane to a solution of the polymer in chloroform. Cross-sectional analysis of the monolith was performed by scanning electron microscopy that unveiled a three-dimensionally networked porous structure inside the monolith. As a result of nitrogen adsorption/desorption experiments, the specific surface area of the monolith was calculated to be 145 m²/g with the Brunauer Emmett Teller equation. The allyl groups of the monolith were subjected to a thiol-ene click reaction with 2-mercaptoethanol and an olefin metathesis with a Grubbs catalyst. With the porous structure largely maintained, the click reaction attained high conversions and the metathesis internally crosslinked the monolith to the degree that confers solvent resistance. These results qualify the present monolith as a versatile platform for chemical transformations into a wide range of functional monoliths.