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Abstract Polymerization‐induced self‐assembly (PISA) has emerged as a scalable one‐pot technique to prepare block copolymer (BCP) nanoparticles. Recently, a PISA process, that results in poly(l‐lactide)‐b‐poly(ethylene glycol) BCP nanoparticles coined ring‐opening polymerization (ROP)‐induced crystallization‐driven self‐assembly (ROPI‐CDSA), was developed. The resulting nanorods demonstrate a strong propensity for aggregation, resulting in the formation of 2D sheets and 3D networks. This article reports the synthesis of poly(N,N‐dimethyl acrylamide)‐b‐poly(l)‐lactide BCP nanoparticles by ROPI‐CDSA, utilizing a two‐step, one‐pot approach. A dual‐functionalized photoiniferter is first used for controlled radical polymerization of the acrylamido‐based monomer, and the resulting polymer serves as a macroinitiator for organocatalyzed ROP to form the solvophobic polyester block. The resulting nanorods are highly stable and display anisotropy at higher molecular weights (>12k Da) and concentrations (>20% solids) than the previous report. This development expands the chemical scope of ROPI‐CDSA BCPs and provides readily accessible nanorods made with biocompatible materials.
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Reaction‐induced morphology control in block copolymers
Abstract Controlling the self‐assembly behaviors of block copolymers (BCPs) is a focal point of many research thrusts due to their broad use in various applications. While BCP molecular weight, volume fraction, and chemical identities are key thermodynamic parameters to determine their morphology, an emergent method in this area is through reaction‐induced changes to the characteristics of a BCPin situ, which provides access to multiple morphologies and domain sizes from a single parent polymer, as well as enabling the formation of metastable morphologies which may be difficult to attain otherwise. This work provides a focused review about the current state of reaction‐induced morphology control in BCPs in both solution and solid states. Furthermore, we provide a forward‐looking perspective on the future opportunities of understanding and employing reaction engineering to manipulate and advance BCP self‐assembly. © 2023 Society of Industrial Chemistry.
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- Award ID(s):
- 2239408
- PAR ID:
- 10433886
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Polymer International
- Volume:
- 72
- Issue:
- 12
- ISSN:
- 0959-8103
- Format(s):
- Medium: X Size: p. 1061-1069
- Size(s):
- p. 1061-1069
- Sponsoring Org:
- National Science Foundation
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