title: Structural evolution of low-molecular-weight poly(ethylene oxide)-block-polystyrene diblock copolymer thin film.
abstract: The structural evolution of low-molecular-weight poly(ethylene oxide)-block-polystyrene (PEO-b-PS) diblock copolymer thin film with various initial film thicknesses on silicon substrate under thermal annealing was investigated by atomic force microscopy, optical microscopy, and contact angle measurement. At film thickness below half of the interlamellar spacing of the diblock copolymer (6.2 nm), the entire silicon is covered by a polymer brush with PEO blocks anchored on the Si substrate due to the substrate-induced effect. When the film is thicker than 6.2 nm, a dense polymer brush which is equal to half of an interlamellar layer was formed on the silicon, while the excess material dewet this layer to form droplets. The droplet surface was rich with PS block and the PEO block crystallized inside the bigger droplet to form spherulite.
authors.affiliation: College of Material Engineering, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wu
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Huang
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry; D057005:Bioengineering; D018625:Microscopy, Atomic Force; D008859:Microscopy, Polarization; D015394:Molecular Structure; D008970:Molecular Weight; D011092:Polyethylene Glycols / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry*; D012825:Silicon; D013499:Surface Properties
chemical_list: D001672:Biocompatible Materials; D011137:Polystyrenes; C541965:polystyrene-b-poly(ethylene oxide); D011092:Polyethylene Glycols; D012825:Silicon