Synthesis of tailored core–brush polymer particles via a living radical polymerization and architecture of colloidal crystals

Polystyrene Brushes on Fully Deuterated Organic Nanoparticles by Surface‐Initiated Nitroxide‐Mediated Radical Polymerization

“…Grafting‐from procedures are more challenging with respect to the thorough characterization of the grafted chains, but allow a much broader variation – from low to high grafting densities – and reliable predetermination of the grafting densities 1, 27, 28. As the latter aspects are especially relevant for our investigations, following surface‐initiated controlled radical polymerization methodologies seem feasible and are already well established29, 30: surface‐initiated atom transfer radical polymerization (SI‐ATRP),31–37 surface‐initiated radical addition and chain transfer (SI‐RAFT) process,22, 38–40 and surface‐initiated nitroxide‐mediated radical polymerization (SI‐NMRP) 41–49. Especially NMRP should be an appropriate choice for growing linear PS from the latex particles' surface while varying the grafting densities over a wide range.…”

Convenient Quantification of Accessible Surface-Attached ATRP Initiators and RAFT Chain Transfer Agents on Cross-Linked Polystyrene Nanoparticles

“…In recent years, nanoparticles attract more and more attention due to their high potential in applications ranging from material sciences to medicine such as electronics, biomedical, pharmaceutical, optics, and catalysis. − Surface-modification of both inorganic and organic particles leads to tunable spheres with core/shell structures that allow, for example, improvement of established materials as well as development of basically new systems. , Since the pioneering work of Prucker and Rühe, , who grafted silica nanoparticles with polystyrene (PS) by a free radical process, many further methodologies came up for so-called surface-initiated polymerization strategies. The “grafting from” approach has the main advantage over the “grafting onto” method in generating remarkably higher grafting densities of surface-anchored polymer chains on the solid substrate. − All above controlled radical polymerization strategies such as atom transfer radical polymerization (ATRP) and the reversible addition–fragmentation chain transfer (RAFT) processes seem to be the most promising routes for decorating particles with high grafting densities resulting in polymer brushes. ,,− By these methods, surfaces of particles have furthermore been modified with stimuli-responsive polymers leading to so-called “smart surfaces”. ,, Especially the surface-grafting of cross-linked polymeric microspheres leads to very interesting materials with a wide range of potential applications. ,− Recently, Barner-Kowollik et al highlighted scope and limitations in polymeric microparticle science …”

Permanent locking of colloidal crystals composed of core‐brush polymeric nanoparticles

“…This was followed by the formation of a grafted polymer brush prepared by photoinduced atom transfer radical polymerization (ATRP). The particle sizes (number‐average particle diameter D n = 190–300 nm) were controlled by varying the temperature, and the size distribution was extremely narrow (D w /D n = ∼1.0001) . By varying the particle size of the colloidal crystals, their brilliant color could be varied throughout the visible spectrum.…”