Synthesis of polymer-vesicle latex particles through an ATRP-based approach

The synthesis of polymer-vesicle latex particles by using extruded vesicles of dimethyldioctadecyl ammonium bromide (DODAB) via an atom transfer radical polymerization–based approach is reported. Cryo-TEM characterization revealed the growth of polymer from one side of the vesicle, and the final morphology of the resulting particles was affected by monomer feed composition. Protrusions or nanocapsules were synthesized when MMA:BA:EGDMA or MMA were used, respectively. Furthermore, it was found that the co-oligomer composition and chain length affect the resulting morphologies of the particles.

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Interaction of Cationic, Anionic, and Nonionic Macroraft Homo- and Copolymers with Laponite Clay

The functionalization of Laponite RD platelets with different cationic, anionic, and nonionic homo- and copolymers synthesized by reversible addition-fragmentation chain transfer (RAFT) has been investigated. The effective interaction of the macromolecular RAFT agents (macroRAFTs) with the inorganic particles is known to be of crucial importance for the successful coating of minerals with polymers via RAFT-mediated emulsion polymerization to produce polymer-encapsulated inorganic particles. The macroRAFT agents synthesized in the present work contain carefully selected reinitiating R groups, which bear either ionizable tertiary amine or quaternary ammonium moieties (from 2-(dimethylamino)ethyl methacrylate, DMAEMA), negatively charged acrylic acid (AA) repeat units, or neutral polyethylene glycol (PEG) side chains, and are capable of interacting with Laponite via different adsorption mechanisms. The equilibrium adsorption of these RAFT (co)polymers was investigated by the plotting of adsorption isotherms, and either L-type or H-type curves were obtained. The hydrophobicity of the macroRAFT was shown to promote adsorption, as did the pending configuration of the PEG block. Charge repulsion between AA and the negatively charged surface of Laponite at pH 7.5, on the other hand, was prejudicial for adsorption, while the strong electrostatic interaction between the cationic DMAEMA molecules and the Laponite surface led to high-affinity-type curves.

Recent advances in colloidal nanocomposite designviaheterogeneous polymerization techniques

Recent advances in colloidal nanocomposite design by heterogeneous polymerization are reviewed, with a specific focus on encapsulation and particle-based stabilization for specific materials applications.

A Roadmap towards Successful Nanocapsule Synthesis via Vesicle Templated RAFT-Based Emulsion Polymerization

Vesicle templated emulsion polymerization is a special form of emulsion polymerization where the polymer is grown from the outside of the vesicle, leading to nanocapsules. Cost effective nanocapsules synthesis is in high demand due to phasing out of older methods for capsule synthesis. Although the first indications of this route being successful were published some 10 years ago, until now a thorough understanding of the parameters controlling the morphologies resulting from the template emulsion polymerization was lacking. Most often a mixture of different morphologies was obtained, ranging from solid particles to pro-trusion structures to nanocapsules. A high yield of nanocapsules was not achieved until now. In this paper, the influence of initial vesicle dispersion, choice of the Reversible Addition-Fragmentation chain Transfer (RAFT) species and oligomer, monomer and crosslinker have been investigated. It turns out that good initial vesicle dispersion, molecular control of the RAFT process, a not too hydrophobic monomer and some crosslinking is needed to result in high yield of nanocapsules. In previous work, the level of RAFT control was often suboptimal and not properly verified and although nanocapsules were shown, other morphologies were also present. We now believe we have a full understanding of vesicle templated nanocapsules synthesis, relevant to many applications.

Nanocomposite latexes containing layered double hydroxides via RAFT-assisted encapsulating emulsion polymerization

Successful encapsulation of LDH nanoplatelets into latex particles.

ATRP mediated encapsulation of Gibbsite: fixation of the morphology by using a cross-linker

Gibbsite platelets were successfully encapsulated using a cross-linker in ATRP-mediated starved feed emulsion polymerisation.

The in situ formation of nanoparticles via RAFT polymerization-induced self-assembly in a continuous tubular reactor

Amphiphilic poly(poly(ethylene glycol)methyl ether methacrylate)-b-poly(methyl methacrylate) (PPEGMA-b-PMMA) diblock copolymer nanoparticles were successfully synthesized via polymerization-induced self-assembly (PISA) at 70 °C in a continuous tubular reactor.

Encapsulation of unmodified Gibbsite via conventional emulsion polymerisation using charged co-oligomers

A simple procedure for the encapsulation of unmodified Gibbsite was developed using conventional emulsion polymerization and charged oligomers as stabilisers.