Self-assembled and Nanostructured Copolymer Aggregations of the Tertiary Amine Methacrylate Based Triblock Copolymers

Abstract

The micellization behavior of novel tertiary amine methacrylate-based ABA type triblock copolymers formed by poly[2-(dimethylamino)ethyl methacrylate] [PDMA] middle block and poly[2-(diethylamino)ethyl methacrylate] [PDEA] or poly[2-(diisopropylamino)ethyl methacrylate] [PDPA] side blocks, PDPA_m-b-PDMA_n-b-PDPA_l, and PDEA_m-b-PDMA_n-b-PDEA_l was investigated. Both types of triblock copolymers were water-soluble and had potential for various applications due to their self-assembled and the bottom-up nanoscale micellar construction. The micellar aggregations of the triblock copolymers in aqueous solutions with varying comonomer ratios, molecular weights, temperatures, and pH values were investigated by small-angle X-ray scattering and dynamic light scattering. Compact micellar aggregations were obtained as 0.5 weight percent solutions at 20–21°C and pH 8.67 to 9.05, and characterized as polydispersed spherical core-shells. One group of triblock copolymer micelles had PDPA-cores with radii from 18 to 21 Å and PDMA-shell thicknesses of 89–105 Å, whereas the other group had PDEA-core spherical micelles with core radii of 60–62 Å and a PDMA-shell thicknesses of 64–66 Å.

Keywords::

• Block copolymer
• DLS
• Dynamic light scattering
• Micelles
• SAXS
• Small-angle X-ray scattering

ACKNOWLEDGMENTS

We would like to thank Prof. Dr. Semra Ide for her scientific comments regarding the SAXS results and data evaluation. The corresponding author is grateful to the NSRRC for measurements performed as part of this work (SWAXS Beamline-Endstation 23A1 for project 2014-2-042-1).