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We have demonstrated directed self-assembly of poly(styrene-b-dimethylsiloxiane) (PS-b-PDMS) down to sub- 10-nm half-pitch by using grating Si substrate coated with PDMS. The strong segregation between PS and PDMS enables us to direct the self-assembly in wide grooves of the grating substrate up to 500 nm in width. This process can be applied to form various type of sub-10-nm stripe pattern along variety of grating shape. V C 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 2297-2301, 2010

The equilibrium properties of polymer brushes formed by starlike polymers with varying number of arms attached to a surface by their center were studied experimentally with neutron reflectrometry (NR). Polystyrene (PS) stars in a good solvent (toluene) were centrally adsorbed onto a quartz substrate via a zwitterionic anchor group. Increasing the number of arms resulted in significantly lower equilibrium adsorbance, while replacement experiments of a 3-armed star brush by linear chains revealed interesting equilibrium and kinetic features related to the special architecture of star polymers. These results are compared with scaling theoretical calculations and Monte Carlo simulations of centrally adsorbed star polymers that were performed under the bond fluctuation simulation scheme. Several features of the experimental results are reproduced in our simulation study.

The formation of homopolymer and block copolymer brushes grafted from Au and Si (SiOx) surfaces via living 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 wafer and Au surfaces, respectively, by self-assembled monolayer techniques. n-BuLi was used to activate the DPE initiator for anionic polymerization of monomers at the interface. A high-vacuum reactor was used for polymerization at surfaces under anhydrous solution conditions. By a careful sequence of monomer introduction, reaction, and termination, homopolymer and block copolymer tethered polymer brushes were obtained. The grafted polymer chains were investigated using surface sensitive techniques such as ellipsometry, contact angle measurements, atomic force microscopy, Fourier transform infrared spectroscopy, surface plasmon spectroscopy, and X-ray photoelectron spectroscopy. The importance of activation of t...