Poly brushes conditions

Based on this approach Schouten et al. [254] attached a silane-functionalized styrene derivative (4-trichlorosilylstyrene) on colloidal silica as well as on flat glass substrates and silicon wafers and added a five-fold excess BuLi to create the active surface sites for LASIP in toluene as the solvent. With THF as the reaction medium, the BuLi was found to react not only with the vinyl groups of the styrene derivative but also with the siloxane groups of the substrate. It was found that even under optimized reaction conditions, LASIP from silica and especially from flat surfaces could not be performed in a reproducible manner. Free silanol groups at the surface as well as the ever-present impurities adsorbed on silica, impaired the anionic polymerization. However, living anionic polymerization behavior was found and the polymer load increased linearly with the polymerization time. Polystyrene homopolymer brushes as well as block copolymers of poly(styrene-f)lock-MMA) and poly(styrene-block-isoprene) could be prepared. 

Recently, core-shell type microgels, which contain a hydrophobic core and a hydrophilic thermosensitive shell, have become attractive for scientists because such systems can combine the properties characteristic of both the core and the shell [53], We have prepared core-shell microgel particles consisting of a poly(styrene) core onto which a shell of polyCA-isopropylacrylamide) (PS-PNIPA) has been affixed in a seeded emulsion polymerization [54-56], In this case, the ends of the crosslinked PNIPA chains are fixed to a solid core, which defines a solid boundary of the network. In this respect, these core-shell latex particles present crosslinked polymer brushes on defined spherical surfaces. The solvent quality can be changed from good solvent conditions at room temperature to poor solvent conditions at a temperature... 

Poly(n-butyl acrylate) brushes were synthesized by activators generated by electron transfer (AGET) ATRP of BA from 2-bromoisobutyrate functionalized silica particles in miniemulsion imder conditions similar to those reported previously, BA Si02-Br CuBr2 BPMODA ascorbic acid = 600 1 0.5 0.5 ... 

Tugulu S, Klok H-A (2008) Stability and nonfouling properties of poly(poly(ethylene glycol) methacrylate) brushes under cell culture conditions. Biomacromolecules 9 906... 

Class D. The class of engineered assemblies includes systems that do not spontaneously form ordered structures under normal conditions. Their classification as SPs can be justified since elements of supramolecular interaction stfil assist the final organization. Some examples are layered assembly of complementary poly electrolytes obtained by stepwise deposition under kinetic control (cf. Chapter 19), and polymer brushes prepared by grafting a polymer chain over a SAM of an initiator [6]. Both approaches allow a fine-tuning of surface properties and patterning possibilities. Tailored performance in applications, such as biocompatibility, biocatalysis, integrated optics and electronics have been considered. Additional differences between self-assembled and engineered SPs are discussed in Section I.C. 

Choi, B. C., Choi, S., Leckband, D. E. (2013). Poly(N-isopropyl acrylamide) brush topography dependence on grafting conditions and temperature. Langmuir, 29, 5841-5850. 

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