Abstract
| - The formation of homopolymer and block copolymer brushes grafted from Au and Si (SiOx) surfaces vialiving anionic surface-initiated polymerization (LASIP) is described. The initiator precursor 1,1-diphenylethylene (DPE) was functionalized with alkylsilane or alkylthiol and grafted onto planar Si waferand Au surfaces, respectively, by self-assembled monolayer techniques. n-BuLi was used to activate theDPE initiator for anionic polymerization of monomers at the interface. A high-vacuum reactor was usedfor polymerization at surfaces under anhydrous solution conditions. By a careful sequence of monomerintroduction, reaction, and termination, homopolymer and block copolymer tethered polymer brusheswere obtained. The grafted polymer chains were investigated using surface sensitive techniques such asellipsometry, contact angle measurements, atomic force microscopy, Fourier transform infrared spectroscopy,surface plasmon spectroscopy, and X-ray photoelectron spectroscopy. The importance of activation of thegrafted initiator, control of polymerization conditions, and removal of excess BuLi is emphasized. Interestingdifferences in morphology, thickness, grafting density, and polymerization conditions contrast LASIP fromsolution and other surface-initiated polymerization mechanisms. The formation of block copolymer sequenceshighlights the unique utility of a living anionic polymerization technique on surfaces.
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