Morphology of Poly[(t-butyl acrylate)-b-styrene-b-isobutylene-b-styrene-b-(t-butyl acrylate)] Pentablock Terpolymers and Their Thermal Conversion to the Acrylic Acid Form
Polymers and High Performance Materials
The morphology of a synthesized poly[(tert-butyl acrylate)-b-styrene-b-isobutylene-b-styrene-(tert butyl acrylate)] pentablock terpolymer was determined using transmission electron microscopy, atomic force microscopy and small angle X-ray scattering methods. The outer blocks of this material were converted to the acrylic acid form by a thermal process that caused a beta-scission reaction in a simple thermal process, as verified by FTIR and NMR spectroscopies as well as thermogravimetric analysis. An initial heat-vacuum treatment induced a morphology that was more disordered relative to the precursor material, but when these samples were recast in THF solvent and annealed again, a considerably more refined and ordered morphology consisting of hexagonally packed cylinders resulted. This simple heat treatment allows for the tert-butyl groups to be converted to acrylic acid groups without dissolving the polymer or further sample cleaning. A dynamic mechanical investigation of the PtBuA form revealed three or two relaxation features depending interpretations based on the presence of three-phase morphology or a two-phase morphology in which there are mixed hard block domains. (C) 2008 Elsevier Ltd. All rights reserved.
Kopchick, J. G.,
Storey, R. F.,
Jarrett, W. L.,
Mauritz, K. A.
(2008). Morphology of Poly[(t-butyl acrylate)-b-styrene-b-isobutylene-b-styrene-b-(t-butyl acrylate)] Pentablock Terpolymers and Their Thermal Conversion to the Acrylic Acid Form. Polymer, 49(23), 5045-5052.
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