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ABSTRACT The 'breath figures' method provides an efficient and cost-effective method to produce highly ordered honeycomb patterns in polymeric films at micrometer and sub-micrometer dimensions. The size and regularity of the pores can be adjusted through a series of physical and chemical parameters. In this study, amphiphilic diblock copolymers, polystyrene- block-poly(4-vinyl pyridine) (PS- b-P4VP) with different lengths of P4VP, were synthesized through Reversible Addition-Fragmentation Chain Transfer polymerization. The honeycomb-patterned films were prepared from these well-defined polymers through the dynamic breath figures method. A series of physical parameters including solution concentration, flow rate, humidity of the flow, and the humidity of the casting environment, were delicately adjusted to systematically investigate their effects on the morphology of the films. These studies identified four key factors which were found to influence the formation of the pattern. No obvious effect was found on the pore size by changing the length of P4VP block. The result provides clear direction on the fabrication of PS- b-P4VP honeycomb-patterned films and more broadly contributes a deeper understanding of the processes involved in the formation of honeycomb patterns. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 3721-3732 [ABSTRACT FROM AUTHOR]

ABSTRACT The arrangement of monomers and morphology of fluorinated copolymers of methyl methacrylate (MMA) were found to be important for controlling the surface energy of the materials when formed into thin films. Novel copolymers of MMA and 2,2,3,3,4,4,4-heptafluorobutyl methacrylate (F3MA) were prepared with different monomer placement, namely statistical and block arrangements of the monomer units. The surface energies decreased with increasing incorporation of F3MA, in a manner consistent with previous reports for similar copolymers; however, the surface energies of the block copolymers were consistently lower than the statistical copolymers. This was interpreted as arising from conformational restriction of presentation of the fluoromonomers to the surface in the statistical copolymers, and formation of phase-separated domains at the surface of the block copolymers. The morphology of the block copolymers was confirmed by small angle X-ray scattering measurements, which allowed calculation of a solubility parameter for the fluorinated segments. The results have implications for the design of more environmentally acceptable materials with ultra-low surface energies. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 2633-2641 [ABSTRACT FROM AUTHOR]