The influence of architecture on polymer interactions is investigated and differences between branched and linear copolymers are found. Four key aspects are addressed: (1) Synergistic Intramolecular Complexation within Miktoarm Stars. The proximity of thermoresponsive poly(propylene oxide) (PPO) and poly(dimethylaminoethyl methacrylate) PDMAEMA within a miktoarm star leads to complexation between these weakly interacting partners. Consequently, the original properties of the constituents are lost, showing hydrophobic domains even at low temperatures, where all homopolymers are water soluble. (2) Prevention of Pronounced Complexation within Diblock Copolymers. In contrast to the star copolymers, PPO and PDMAEMA adapt rather their homopolymer behavior within the respective diblock copolymers. (3) Unimolecular Micelles for Miktoarm Stars. The star does not exhibit intermolecular self-assembly in a large temperature range. This behavior was traced back to a reduced interfacial tension between the PPO/PDMAEMA complex and water (PDMAEMA acts as �microsurfactant�). (4) Two-Step Micellization for Diblock Copolymers. Upon heating of linear copolymers, the dehydration of PPO is followed by self-assembly into spherical micelles. An intermediate prevalence of unimolecular micelles is revealed in a small temperature window between PPO collapse and the concomitant self-assembly. In summary, advanced macromolecular architectures can lead to an unprecedented intramolecular self-assembly behavior, where internal complexation prevents intermolecular aggregation.

Architectural effects on the stability of thermosensitive unimeric micelles

248th National Meeting (2014)

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