SANS Study of Coated Block Copolymer Micelles

✍ Scribed by Josef Pleštil; Jaroslav Kříž; Čestmír Koňák; Herman Pospíšil; Petr Kadlec; Zdeňka Sedláková; Isabelle Grillo; Robert Cubitt

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 193 KB
• Volume: 206
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.200400543

✦ Synopsis

Abstract

Summary: Multishell particles were prepared by γ‐radiation‐induced polymerization of methyl methacrylate (MMA) in polystyrene‐block‐poly(methacrylic acid) (PS‐b‐PMA) aqueous micellar solution and their structure was studied by small‐angle neutron scattering (SANS). Before polymerization, almost all MMA molecules are distributed in aqueous phase and only 1% of MMA is accumulated inside the micelles. The newly formed polymer (PMMA) is deposited on the surface of PS cores of the original micelles. The effect of the MMA concentration, micelle concentration, absorbed radiation dose, and absorbed dose rate on the characteristics of the resulting particles was examined. The thickness of the PMMA shell (20–218 Å for the presented series of samples) can be easily controlled by variation of monomer and/or micelle concentration. Universal plots of the core volume (PS+PMMA) and SANS curve were presented. These plots facilitate choosing proper monomer and micelle concentrations and detecting possible irregularities in the parameters of the resulting particles.
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