title: Effect of Monomer Solubility on the Evolution of Copolymer Morphology during Polymerization-Induced Self-Assembly in Aqueous Solution.
abstract: Polymerization-induced self-assembly (PISA) has become a widely used technique for the rational design of diblock copolymer nano-objects in concentrated aqueous solution. Depending on the specific PISA formulation, reversible addition-fragmentation chain transfer (RAFT) aqueous dispersion polymerization typically provides straightforward access to either spheres, worms, or vesicles. In contrast, RAFT aqueous emulsion polymerization formulations often lead to just kinetically-trapped spheres. This limitation is currently not understood, and only a few empirical exceptions have been reported in the literature. In the present work, the effect of monomer solubility on copolymer morphology is explored for an aqueous PISA formulation. Using 2-hydroxybutyl methacrylate (aqueous solubility = 20 g dm-3at 70 °C) instead of benzyl methacrylate (0.40 g dm-3at 70 °C) for the core-forming block allows access to an unusual "monkey nut" copolymer morphology over a relatively narrow range of target degrees of polymerization when using a poly(methacrylic acid) RAFT agent at pH 5. These new anisotropic nanoparticles have been characterized by transmission electron microscopy, dynamic light scattering, aqueous electrophoresis, shear-induced polarized light imaging (SIPLI), and small-angle X-ray scattering.
authors.affiliation: Dainton Building, Department of Chemistry, The University of Sheffield , Brook Hill, Sheffield, South Yorkshire S3 7HF, U.K.
authors.forename: Amy A
authors.initials: AA
authors.lastname: Cockram
authors.affiliation: Dainton Building, Department of Chemistry, The University of Sheffield , Brook Hill, Sheffield, South Yorkshire S3 7HF, U.K.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Neal
authors.affiliation: Dainton Building, Department of Chemistry, The University of Sheffield , Brook Hill, Sheffield, South Yorkshire S3 7HF, U.K.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Derry
authors.affiliation: Dainton Building, Department of Chemistry, The University of Sheffield , Brook Hill, Sheffield, South Yorkshire S3 7HF, U.K.
authors.forename: Oleksandr O
authors.initials: OO
authors.lastname: Mykhaylyk
authors.affiliation: AkzoNobel Decorative Paints, Wexham Road, Slough, Berkshire SL2 5DS, U.K.
authors.forename: Neal S J
authors.initials: NS
authors.lastname: Williams
authors.affiliation: AkzoNobel Decorative Paints, Wexham Road, Slough, Berkshire SL2 5DS, U.K.
authors.forename: Martin W
authors.initials: MW
authors.lastname: Murray
authors.affiliation: AkzoNobel Decorative Paints, Wexham Road, Slough, Berkshire SL2 5DS, U.K.
authors.forename: Simon N
authors.initials: SN
authors.lastname: Emmett
authors.affiliation: Dainton Building, Department of Chemistry, The University of Sheffield , Brook Hill, Sheffield, South Yorkshire S3 7HF, U.K.
authors.forename: Steven P
authors.initials: SP
authors.lastname: Armes