The synthesis of a series of co-oligomer amphiphiles by RAFT and their self-assembly behavior in water is described. These novel amphiphiles, comprised of styrene, butyl acrylate, and alkyl hydrophobes together with ionic acrylic acid and nonionic hydroxyethylacrylate hydrophilic moieties and with a total degree of polymerization from 5 to 17, represent a new class of small-molecule surfactants that can be formed from the immense potential library of all polymerizable monomers. Examples of micellar solutions and discrete cubic, hexagonal, lamellar, and inverted hexagonal lyotropic phases, as well as vesicle dispersions and coexisting lamellar phases, are reported and characterized by small-angle scattering. The variation of self-assembly structure with co-oligomer composition, concentration, and solution conditions is interpreted by analogy with the surfactant packing parameter used for conventional small-molecule amphiphile ABSTRACT: The synthesis of a series of co-oligomer amphiphiles by RAFT and their self-assembly behavior in water is described. These novel amphiphiles, comprised of styrene, butyl acrylate, and alkyl hydrophobes together with ionic acrylic acid and nonionic hydroxyethylacrylate hydrophilic moieties and with a total degree of polymerization from 5 to 17, represent a new class of smallmolecule surfactants that can be formed from the immense potential library of all polymerizable monomers. Examples of micellar solutions and discrete cubic, hexagonal, lamellar, and inverted hexagonal lyotropic phases, as well as vesicle dispersions and coexisting lamellar phases, are reported and characterized by small-angle scattering. The variation of self-assembly structure with co-oligomer composition, concentration, and solution conditions is interpreted by analogy with the surfactant packing parameter used for conventional small-molecule amphiphiles.

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In this article, we report the manipulation of block terpolymer morphology through control of the segment distribution. We consider a model system comprised of three acrylic monomers: hydrophilic poly(hydroxyethyl acrylate) (H), hydrophobic poly(octyl acrylate) (O), and polar poly(methyl acrylate) (M). For each of four chemical compositions, we altered the M segment distribution in four terpolymer architectures with reversible addition–fragmentation chain transfer (RAFT) polymerization to yield: two triblock terpolymer architectures, HOM and HMO, and two diblock terpolymer architectures, HM/O and H/MO, where the M segments are statistically distributed in the O or H blocks, respectively. Using a combination of small-angle X-ray scattering and dynamic shear rheology, we illustrate how the monomer distribution can be used to manipulate the thermodynamic behavior of terpolymers at constant chemical composition. These results will be of use to those wishing to partially decouple the formulation of a block copolymer from its morphology.

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