title: Amphiphilic cross-linked networks produced from the vulcanization of nanodomains within thin films of poly(N-vinylpyrrolidinone)-b-poly(isoprene).
abstract: Diblock copolymers of poly(N-vinylpyrrolidinone) (PNVP) and poly(isoprene) (PIp) were employed as building blocks for the construction of complex cross-linked networks that present surfaces having amphiphilic character, imparted by covalent trapping of compositionally heterogeneous phase-separated morphologies. The kinetics for the homopolymerization of N-vinylpyrrolidinone by reversible addition-fragmentation chain transfer (RAFT) techniques was studied, and the initially obtained PNVP-based macro-RAFT agents were then extended to PNVP-b-PIp block copolymers. Therefore, the PNVP chain length was held constant at a number-averaged degree of polymerization of 120, while the PIp chain length was varied to afford a series of three PNVP120-b-PIpx block copolymers (where x=710, 53, and 25). These materials were then cross-linked individually using sulfur monochloride, to produce complex amphiphilic networks. The nanoscopically resolved topographies of these films were analyzed using atomic force microscopy, and their compositional heterogeneities were probed by X-ray photoelectron spectroscopy and internal reflectance infrared imaging techniques. Additionally, the surfaces were analyzed to determine the extent of surface reorganization under aqueous conditions.
authors.affiliation: Department of Chemistry, Washington University in Saint Louis, Saint Louis, MO 63130-4899, USA.
authors.forename: Jeremy W
authors.initials: JW
authors.lastname: Bartels
authors.forename: Peter L
authors.initials: PL
authors.lastname: Billings
authors.forename: Biswajit
authors.initials: B
authors.lastname: Ghosh
authors.forename: Marek W
authors.initials: MW
authors.lastname: Urban
authors.forename: C Michael
authors.initials: CM
authors.lastname: Greenlief
authors.forename: Karen L
authors.initials: KL
authors.lastname: Wooley
mesh_terms: D002070:Butadienes / Q000737:chemistry*; D003432:Cross-Linking Reagents / Q000737:chemistry*; D045782:Hemiterpenes / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D018625:Microscopy, Atomic Force; D015394:Molecular Structure; D036103:Nanotechnology; D010420:Pentanes / Q000737:chemistry*; D011145:Polyvinyls / Q000737:chemistry*; D011760:Pyrrolidinones / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D002070:Butadienes; D003432:Cross-Linking Reagents; D045782:Hemiterpenes; D010420:Pentanes; D011145:Polyvinyls; D011760:Pyrrolidinones; D014867:Water; C005059:isoprene