Solvent-non-solvent rapid-injection for preparing nanostructured materials from micelles to hydrogels

Abstract

Due to their distinctive molecular architecture, ABA triblock copolymers will undergo specific self-assembly processes into various nanostructures upon introduction into a B-block selective solvent. Although much of the focus in ABA triblock copolymer self-assembly has been on equilibrium nanostructures, little attention has been paid to the guiding principles of nanostructure formation during non-equilibrium processing conditions. Here we report a universal and quantitative method for fabricating and controlling ABA triblock copolymer hierarchical structures using solvent-non-solvent rapid-injection processing. Plasmonic nanocomposite hydrogels containing gold nanoparticles and hierarchically-ordered hydrogels exhibiting structural color can be assembled within one minute using this rapid-injection technique. Surprisingly, the rapid-injection hydrogels display superior mechanical properties compared with those of conventional ABA hydrogels. This work will allow for translation into technologically relevant areas such as drug delivery, tissue engineering, regenerative medicine, and soft robotics, in which structure and mechanical property precision are essential.

Controlling nanostructure and mechanical properties in triblock copolymer/monomer blends via reaction-induced phase transitions

“…Although synthetic improvements for controlling polymer topology and chemical composition have led to TPE advances, there are a wealth of opportunities in utilizing in situ reaction and processing modalities to tune macromolecular structures and nanoscale phases not easily accessible via traditional methods. [8][9][10][11] The molecular architecture of TPEs is based on a block polymer framework in which covalent bonds chemically link distinct repeat segments or ''blocks'' (e.g., A or B blocks in an ABA triblock copolymer) to form a single macromolecule. 12 Block polymers will microphase separate into distinct domains as a result of the incompatibility between the polymer blocks.…”

Surface-Initiated Ring-Opening Metathesis Polymerization: A Method for Synthesizing Polymer-Functionalized Nanoparticles Exhibiting Semicrystalline Properties and Diverse Macromolecular Architectures

“…Polymer/inorganic nanoparticle hybrids are a class of materials that are designed to enhance material properties by introducing inorganic functionality and by increasing component interfacial contact. − The combination of nanoscale objects (oxides, metals, or semiconductors) with polymers results in hybrid materials with advanced optical, − magnetic, − electrical, and mechanical properties . However, for hybrid materials to achieve advanced properties, the inorganic nanoparticles often need to be homogeneously dispersed within the polymer matrix at high particle loadings. − In practice, dispersing particles into a polymer phase and organizing them into hierarchical nanostructures is challenging because of the thermodynamic phase separation of inorganic and organic components. − A successful way to reduce the enthalpic driving forces to phase separation and improve component dispersion is to graft the same polymer to the nanoparticle surface as the polymer matrix …”

Multiplex fluorescence imaging‐guided programmed delivery of doxorubicin and curcumin from a nanoparticles/hydrogel system for synergistic chemotherapy

“…Linear triblock amphiphilic copolymers have been broadly used to from physically cross‐linked nanoparticles or gels 36 . The hydrophobic polymers will form interconnected domains supporting the nanoparticles or gels.…”

“…Linear triblock amphiphilic copolymers have been broadly used to from physically cross-linked nanoparticles or gels. 36 The hydrophobic polymers will form interconnected domains supporting the nanoparticles or gels. The hydrophobic PCL blocks segregate into separate micellar domains, while the mid PEG-blocks bridges the two domains.…”