Polymer-grafted nanoparticles response

Paris, J.L., Cabanas, M.V., Manzano, M., Vallet-Regi, M., 2015. Polymer-grafted mesoporous silica nanoparticles as ultrasound-responsive drug carriers. ACS Nano 9 (11), 11023-11033. 

The linear viscoelastic properties in the melt state of highly grafted polymers on spherical silica nanoparticles are probed using linear dynamic oscillatory measurements and linear stress relaxation measurements. While the pure silica tethered polymer nanocomposite exhibits solid-like response, the addition of a matched molecular weight free matrix homopolymer chains to this hybrid material, initially lowers the modulus and later changes the viscoelastic response to that of a liquid. These results are consistent with the breakdown of the ordered mesoscale structure, characteristic of the pure hybrid and the high hybrid concentration blends, by the addition of homopolymers with matched molecular weights. 

Generally, the conditions leading to a CRP system were found to yield a well-defined polymer shell. In some examples, the latter was a classical hydrophobic polymer such as polyMMA [158,160], polyMA [158], polystyrene [163], poly(tert-butyl acrylate) [163], or polyBMA [163]. In one example, the grafted polymer was polyDMAEMA, which showed pH- and temperature-responsive behavior when the particles were further transferred to water [159]. The polyDMAEMA domains were used as nanoreactors to generate gold nanoparticles at the particle surface, the catalytic activity of which was effective in the reduction of 4-nitrophenol by NaBILj... 

Mazurowski, M., Gallei, M., Li, J., Didzoleit, H., Stiihn, B., Rehahn, M. (2012). Redox-responsive polymer brushes grafted from polystyrene nanoparticles by means of surface initiated atom Transfer radical polymerization. Macromolecules, 45, 8970-8981. 

Ordered mesoporous silica nanoparticles have shown significant potential for use as biomedical devices, such as drug delivery carriers [182]. In one example, a thermoresponsive polymer, PNIPAM, was grafted onto porous substrates, which allowed formation of surface-responsive properties in the pores [183]. The conformation change of PNIPAM brushes with temperature was used to initiate the... 

Fei Li, Hong Wu, Fan Li, Hui Zhang, et al. Study of Dual Responsive Dex-MA-graft-PNIPAAm hydrogel nanoparticles preparation, characterization and biological evaluation. Polymer International. Early View. 

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