title: Large-scale structure in gels of attractive block copolymer micelles.
abstract: We have used ultra-small-angle scattering (USANS) and fluorescence microscopy to demonstrate the existence of a nonfractal large-scale structure in attractive micellar gels of poly(styrene)-poly(acrylic acid) block copolymers, which have some characteristics of attractive colloidal glasses. The nature of the large-scale structure appears to depend systematically on the strength of attraction. Our systems display scattering that follows I approximately q(x) in the low q regime, with x varying from approximately -3 to -4 as the strength of attraction is decreased. This scattering behavior appears to be the result of surface scattering from large, highly polydisperse aggregates with rough interfaces.
authors.affiliation: Department of Chemical Engineering, University of Massachusetts Amherst, 686 North Pleasant Street, Amherst, Massachusetts 01003, USA.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Crichton
authors.forename: Surita R
authors.initials: SR
authors.lastname: Bhatia