Microphase Separation Behavior on the Surfaces of Poly(dimethylsiloxane)-block-poly(2,2,3,3,4,4,4-heptafluorobutyl methacrylate) Diblock Copolymer Coatings

摘要

Microphase separation behavior on the surfaces of poly(dimethylsiloxane)-block-poly(2,2,3,3,4,4,4-heptafluorobutyl methacrylate) (PDMS-b-PHFBMA) diblock copolymer coatings was investigated. The PDMS-b-PHFBMA diblock copolymers were successfully synthesized via atom transfer radical polymerization (ATRP). The chemical structure of the copolymers was characterized by nuclear magnetic resonance and Fourier transform infrared spectroscopy. Surface composition was studied by X-ray photoelectron spectroscopy. Copolymer microstructure was investigated by atomic force microscopy. The microstructure observations show that well-organized phase-separated surfaces consist of hydrophobic domain from PDMS segments and more hydrophobic domain from PHFBMA segments in the copolymers. The increase in the PHFBMA content can strengthen the microphase separation behavior in the PDMS-b-PHFBMA diblock copolymers. And the increase in the annealing temperature can also strengthen the microphase separation behavior in the PDMS-b-PHFBMA diblock copolymers. Moreover, Flory-Huggins thermodynamic theory was preliminarily used to explain the microphase separation behavior in the PDMS-b-PHFBMA diblock copolymers.