We report the synthesis of a Y‐shaped inimer that contains two orthogonal initiators for ATRP and NMP. The inimer is synthesized through a one‐pot multi‐component reaction that vastly simplifies the typically cumbersome synthesis of similar compounds. The Y‐inimer has the versatility to be homopolymerized into a backbone for A/B Janus bottlebrush synthesis or copolymerized with glycidyl methacrylate (GMA) and cross‐linked into an ultra‐thin coating for mixed A/B brush growth from planar surfaces. Importantly, the Y‐shaped nature of the inimer ensures growth of A and B brushes are consistently in a 1:1 ratio. We demonstrate the application of the Y‐inimer in the synthesis of a PMMA/PS Janus bottlebrush as well as two different mixed A/B polymer brushes, one with the ability to microphase separate, and a second mixed polyelectrolyte brush with opposite charges. The inimer is compatible with various A/B monomer systems and offers a universal approach to the “grafting‐from” polymerization of dual vinyl polymer side chains. This study provides a unique way of utilizing multi‐component reactions in polymer chemistry to access complex functional architectures.
This content will become publicly available on July 16, 2025
Unlike inorganic nanoparticles, organic nanoparticles (oNPs) offer the advantage of “interior tailorability,” thereby enabling the controlled variation of physicochemical characteristics and functionalities, for example, by incorporation of diverse functional small molecules. In this study, a unique inimer-based microemulsion approach is presented to realize oNPs with enhanced control of chemical and mechanical properties by deliberate variation of the degree of hyperbranching or cross-linking. The use of anionic cosurfactants led to oNPs with superior uniformity. Benefitting from the high initiator concentration from inimer and preserved chain-end functionality during atom transfer radical polymerization (ATRP), the capability of oNPs as a multifunctional macroinitiator for the subsequent surface-initiated ATRP was demonstrated. This facilitated the synthesis of densely tethered poly(methyl methacrylate) brush oNPs. Detailed analysis revealed that exceptionally high grafting densities (~1 nm−2) were attributable to multilayer surface grafting from oNPs due to the hyperbranched macromolecular architecture. The ability to control functional attributes along with elastic properties renders this “bottom-up” synthetic strategy of macroinitiator-type oNPs a unique platform for realizing functional materials with a broad spectrum of applications.
more » « less- Award ID(s):
- 2209587
- PAR ID:
- 10572055
- Publisher / Repository:
- National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 121
- Issue:
- 29
- ISSN:
- 0027-8424
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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