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The size and shape of polymer materials is becoming an increasingly important property in accessing new functions and applications of nano‐/microparticles in many scientific fields. New synthetic methods have allowed unprecedented capability for the facile fabrication of anisotropic and shape‐defined nanomaterials. Bottom‐up approaches including: emulsion polymerization techniques, amphiphile self‐assembly, and polymerization‐induced self‐assembly, can lead to polymer particles with precise dimensions in the nanoscale. Top‐down methods such as lithographic templating, and 3D printing, have increased the access to unique particle shapes. In this review, these recent developments are appraised and contrasted, with future research directions providing that focus on biomedical applications. Finally, the opportunity available for synergistic combinations of top‐down and bottom‐up fabrication approaches in realizing previously unattainable architectures and material properties is highlighted.
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Microfluidic-supported synthesis of anisotropic polyvinyl methacrylate nanoparticles via interfacial agents
For polymer particles, recent studies emphasized that the particle shape—not size—plays the dominant role in novel applications in fields ranging from nanotechnology, biomedicine, to photonics, which has intensified the quest for fabrication platforms of polymer colloids with complex non-spherical (anisotropic) shapes. Here, we developed a single-step, microfluidic-supported synthesis for anisotropic polyvinyl methacrylate (PVMA) nanoparticles (NPs) by combining the advantages of microfluidics (providing homogeneous conditions for the initial emulsification process) and bulk batch synthesis (providing inhomogenous conditions for the thermal polymerization). Specifically, we tested five interfacial agents regarding their direct impact on the NP shape (from isotropic spherical to anisotropic flower-like shapes) and their concentration-dependent impact (from 0.1 mM to 20 mM) on the NP diameter (from 200 nm to 50 nm). We employed vinyl methacrylate (VMA), a monomer offering two-polymerization active sites. With our work, we contribute to a fundamental understanding of colloidal polymerization towards predictive shapes below the critical 200 nm regime.
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- PAR ID:
- 10351568
- Date Published:
- Journal Name:
- Polymer Chemistry
- Volume:
- 13
- Issue:
- 32
- ISSN:
- 1759-9954
- Page Range / eLocation ID:
- 4625 to 4633
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D1PY01729B
