The behaviour of honeycomb film formation from star polymers with various fluorine content

A series of poly((1H,1H-pentafluoropropyl acrylate)-ran-(methyl methacrylate)) (poly(PFPA-ran-MMA)) star polymers with varying fluorine content were prepared via the core-first approach using atom-transfer radical polymerisation (ATRP). Subsequently, the star polymers were used to prepare honeycomb films on both planar and non-planar surfaces via the ‘Breath Figures’ technique using a static casting method. The fluorine content of the star polymers was observed to influence the morphology of the honeycomb structures and the formation of non-cracking honeycomb films on non-planar surfaces. Moreover, the average pore diameter of the honeycomb films was found to decrease with increasing fluorine content, as well as increasing polymer concentration in the casting solution or decreasing humidity during casting. The increasing fluorine content of the star polymers was also found to result in a decrease in their glass transition temperatures and Youngʹs modulus values.