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This review describes the most recent progress in the use of polymer multiresponsive microgels as central components of advanced, functional colloidal materials. Significant areas of development include the use of microgels as microreactors for templated synthesis of inorganic nanoparticles with predetermined properties, as optically active materials including lenses and photonic crystals, and as primary units in site-specific and controlled drug delivery systems. In the last category, both synthetic and biopolymeric microgels are discussed. [ABSTRACT FROM AUTHOR]

Nanoparticle (NP) dispersions are extensively used for the producing nanocomposite materials. Optimization of formulations of NP dispersions is a time- and labor-consuming process that can benefit from high-throughput preparation of composite materials, followed by studies of their structure-property relationships. This paper describes a microfluidic platform for producing photopolymerized films from NP-monomer dispersions. The platform enables rapid and reproducible preparation of films with varying compositions by tuning the flow rates of the monomer and NP-monomer mixtures, along with suppressed evaporation of volatile monomers, no need of an inert atmosphere, and the reduced exposure to potentially harmful monomers and NPs. This work paves the way for efficient studies of composition-dependent properties of nanocomposite materials. [ABSTRACT FROM AUTHOR]

Self-organization of nanoparticles is an efficient strategy for producing nanostructures with complex, hierarchical architectures. The past decade has witnessed great progress in nanoparticle self-assembly, yet the quantitative prediction of the architecture of nanoparticle ensembles and of the kinetics of their formation remains a challenge. We report on the marked similarity between the self-assembly of metal nanoparticles and reaction-controlled step-growth polymerization. The nanoparticles act as multifunctional monomer units, which form reversible, noncovalent bonds at specific bond angles and organize themselves into a colloidal polymer. We show that the kinetics and statistics of step-growth polymerization enable a quantitative prediction of the architecture of linear, branched, and cyclic self-assembled nanostructures; their aggregation numbers and size distribution; and the formation of structural isomers. [ABSTRACT FROM AUTHOR]

We studied the optical properties of hybrid multilayer microspheres (HMMs). We prepared multilayer particles with alternating radial layers of gold nanoparticles (NPs) and poly(methyl methacrylate) and achieved control over particle size, the thickness of particle layers, and the surface coverage of gold NPs. We showed the ability to tune the spectral characteristics of the HMMs, which was based on frequency dispersion of the dielectric constant of polymer–metal NP structures. Good agreement between experimental and theoretical extinction properties of the HMMs was obtained. In comparison with multilayer structures synthesized solely from polymers, hybrid multilayer microspheres have a larger refractive layer contrast between adjacent layers, which is important for practical applications in optoelectronic devices. [ABSTRACT FROM AUTHOR]