Amphiphilic cross-linked networks produced from the vulcanization of nanodomains within thin films of poly(N-vinylpyrrolidinone)-b-poly(isoprene).
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.
Bartels
Jeremy W
JW
Department of Chemistry, Washington University in Saint Louis, Saint Louis, MO 63130-4899, USA.
Billings
Peter L
PL
Ghosh
Biswajit
B
Urban
Marek W
MW
Greenlief
C Michael
CM
Wooley
Karen L
KL
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*
D002070:Butadienes; D003432:Cross-Linking Reagents; D045782:Hemiterpenes; D010420:Pentanes; D011145:Polyvinyls; D011760:Pyrrolidinones; D014867:Water; C005059:isoprene