Anisotropic polymer nanoparticles with controlled dimensions from the morphological transformation of isotropic seeds

Abstract

Understanding and controlling self-assembly processes at multiple length scales is vital if we are to design and create advanced materials. In particular, our ability to organise matter on the nanoscale has advanced considerably, but still lags far behind our skill in manipulating individual molecules. New tools allowing controlled nanoscale assembly are sorely needed, as well as the physical understanding of how they work. Here, we report such a method for the production of highly anisotropic nanoparticles with controlled dimensions based on a morphological transformation process (MORPH, for short) driven by the formation of supramolecular bonds. We present a minimal physical model for MORPH that suggests a general mechanism which is potentially applicable to a large number of polymer/nanoparticle systems. We envision MORPH becoming a valuable tool for controlling nanoscale self-assembly, and for the production of functional nanostructures for diverse applications.

Overcoming the Necessity of a Lateral Aggregation in the Formation of Supramolecular Polymer Bottlebrushes in Water

“…[ 1 ] Recently, more attention has been paid to introducing motifs capable of forming directional, supramolecular interaction forces such as π–π interactions or hydrogen bonds (H‐bonds) that can allow to direct the polymer assembly into elongated structures, such as cylinders, that would otherwise not be accessible. [ 2–7 ] In particular, the so‐called supramolecular polymer bottlebrushes (SPBs) have gained increasing interest due to their potential applications in areas such as nanomedicine, [ 8 ] rheology [ 9 ] , electronics, and photonics. [ 10,11 ]…”

Synthesis and applications of anisotropic nanoparticles with precisely defined dimensions

“…Although there have been recent reports using more unusual interactions as the basis for seeded growth, such as hydrogen bonding, 198 π-π interactions 287 and metal-metal bonding 288 , we believe a priority for the field should be the identification of growth mechanisms that enable the controlled growth of nanostructures based on amorphous materials. A recently proposed approach, based on a morphological transformation process (MORPH) exploits supramolecular bonding to drive insertion of a polymer into a spherical seed nanoparticle, coupled with careful design of the polymers' physical properties, to control growth of amorphous, high aspect ratio wormlike nanoparticles 289 . A physical model developed to describe this 'morphological transformation' process suggested that it should be possible to use other supramolecular bonding interactions to achieve similar results.…”

Mapping the Morphological Landscape of Oligomeric Di-block Peptide Polymer Amphiphiles

“…Most peptide amphiphiles are especially proficient at forming rigid cylindrical micelles, because inter-amphiphile hydrogen bonding provides a strong driving force towards anisotropy. [42][43][44] In fact, considerable research has been dedicated to modulating this behavior in peptide-lipid conjugates, primarily by altering the peptide sequence to control inter-amphiphile interactions. [4,[45][46][47] This series of XTEN2-based PPAs have a self-assembly space that more closely resembles block copolymers, which typically have a narrow regime for anisotropic particles that are flexible.…”