Enhanced surface segregation of poly(methyl methacrylate) end-capped with 2-perfluorooctylethyl methacrylate by introduction of a second block

New fluorinated copolymers of poly(methyl methacrylate)-b-poly(butyl methacrylate) or poly(n-octadecyl methacrylate) end-capped with 2-perfluorooctylethyl methacrylate (PMMAx-b-PBMAy-ec-PFMAz or PMMAx-b-PODMAy-ec-PFMAz) were synthesized by living atom transfer radical polymerization. Thin films made of PMMA230-b-PODMAy-ec-PFMA1 were characterized by differential scanning calorimetry, angle-resolved X-ray photoelectron spectroscopy and X-ray diffraction. These films were found to exhibit robust surface segregation of the end groups. Furthermore, the fluorine enrichment factor at the film surface was found to increase linearly with increasing degree of polymerization of poly(n-octadecyl methacrylate) and its increasing fusion enthalpy in the second block, which enhances the segregation of the fluorinated moieties.

Graphical abstractThe segregation of the fluorinated moieties in end-capped poly(methyl methacrylate)-b-poly(n-octadecyl methacrylate) was greatly enhanced by the crystallinity of poly(n-octadecyl methacrylate) block.Figure optionsDownload full-size imageDownload high-quality image (64 K)Download as PowerPoint slideHighlights► New fluorinated diblock copolymers were synthesized. ► Thin films made of these polymers exhibit robust surface segregation. ► Fluorine enrichment factor increase linearly with increasing PODMA fusion enthalpy. ► Self-assembly process imparts synergistically a higher degree of PODMA crystallinity.