Poly brushes atom transfer radical

In this review, synthesis of block copolymer brushes will be Hmited to the grafting-from method. Hussemann and coworkers [35] were one of the first groups to report copolymer brushes. They prepared the brushes on siUcate substrates using surface-initiated TEMPO-mediated radical polymerization. However, the copolymer brushes were not diblock copolymer brushes in a strict definition. The first block was PS, while the second block was a 1 1 random copolymer of styrene/MMA. Another early report was that of Maty-jaszewski and coworkers [36] who reported the synthesis of poly(styrene-h-ferf-butyl acrylate) brushes by atom transfer radical polymerization (ATRP). 

Thermally responsive polymers, such as poly( V-isopropyl acrylamide) (NI-PAm), have also been studied extensively for applications related to those previously discussed [112], De las Heras et al. described the synthesis and patterning of NIPAm brushes on SAMs and their subsequent performance during temperature-dependent adhesion assays of BSA and Streptococcus mutans (Fig. 7). The authors employed p.CP to pattern features of hydrophobic hexadecanethiol and backfilled the surface with an initiator-functionalized alkanethiol. Polymer brushes were grown via surface-initiated atom transfer radical polymerization (ATRP). FITC-BSA was then... 

Ramakrishnan A, Dhamodharan R, Ruhe J. Growth of poly(methyl methacrylate) brushes on silicon surfaces by atom transfer radical polymerization. J Polym Sci Pol Chem 2006 44 (5) 1758-69. 

Using an original approach, Zhang and coworkers recently reported the synthesis of PMMA latex particles stabilized by MMT platelets tethered with poly[2-(dimethylamino)ethyl methacrylate] (PDMAEMA) brushes (Fig. 33) [290]. The PDMAEMA polyelectrolyte brush was synthesized by atom transfer radical polymerization using a cationic initiator previously introduced in the clay galleries. The PDMAEMA-functionaUzed clay platelets were further used to stabilize the emulsion polymerization of MMA initiated by the remaining free radical initiator present on the clay surface. 

Next, in order to demonstrate the efficacy of this cell surface engineering approach, cell microarrays were prepared using a micropattemed poly(2-methacryloyloxyethyl phosphorylcholine [MPC]) (PMPC) polymer brush surface as the substrate. PMPC brushes were prepared on a silicon (Si) wafer via surface-initiated atom transfer radical polymerization, as previously described elsewhere [35]. Selective decomposition of the initiators immobilized on the Si wafer using UV light irradiation resulted in micropatterning of the... 

Parnell, A. J., Martin, S. J., Dang, C. C., Geoghegan, M., Jones, R. A. L., Crook, C. J., et al. (2009). Synthesis, characterization and sweUing behaviour of poly(methacrylic acid) brushes synthesized using atom transfer radical polymerization. Polymer, 50, 1005-1014. 

Lokuge, L, Wang, X., Bohn, P. W. 2007. Temperature-controlled flow switching in nanocapillary array membranes mediated by poly(N-isopropylacrylamide) polymer brushes grafted by atom transfer radical polymerization, 23 305-311. 

Wang, X., Tu, H., Braun, RV., and Bohn, P.W 2006. Length scale heterogeneity in lateral gradients of poly(N-isopropylacrylamide) polymer brushes prepared by surface-initiated atom transfer radical p>olymeiization coupled with in-plane electrochemical potential gradients. Tanomuir 22 817-823. 

Topham, P., Howse, J.R., Crook, C.J., PameU, A.J., Geoghegan, M., Jones, R.A.L., Ryan, A. J. 2006. Controlled Growth of Poly(2-(Diethylamino)Ethyl Methacrylate) Brushes via Atom Transfer Radical Polymerisation on Planar Silicon Surfaces. Polvm. Int. 55 808-815. 

Wu, T, Zhang, Y.F., Wang, X.F., Liu, S.Y. 2008. Fabrication of Hybrid Silica Nanoparticles Densely Grafted with Thermoresponsive Poly(N-Isopropylacrylamide) Brushes of Controlled Thickness via Surface-Initiated Atom Transfer Radical Polymerization. 20 101-109. 

Kizhakkedathu, J. N., Takacs-Cox, A., and Brooks, D. E. 2002. Synthesis and characterization of jxjlymer brushes of poly(N//-dimethylacrylamide) from polystyrene latex by aqueous atom transfer radical polymerization. 

Tugulu, S., Barbey, R., Harms, M., Fricke, M., Volkmer, D., Rossi, A., Klok, H.-A., S5mthesis of Poly(Methacrylic Acid) Brushes via Surface-Initiated Atom Transfer Radical Polymerization of Sodium Methacrylate and Their Use as Substrates for the Mineralization of Calcium Carbonate, g amolecules 2007, 40,168-177. 

This technology has been expanded to prepare intelligent nanocapsules with temperature-responsive cross-linked shells and pH-responsive brushes on their inner walls. These nanocapsules have been prepared by the surface-initiated atom transfer radical polymerization (SI-ATRP) technique with sihca NP as the sacrificial templates. The two-step, sequential SI-ATRP procedure provided the poly(tert-butyl acrylate) (PtBA) brushes on the inner walls of the temperature-responsive cross-linked poly(A-isopropylacryl-amide) (PNIPAA) shells. Then the ester groups in the nanocapsules were transformed chemically into carboxyl groups after etching the silica templates with HF (Mu and Liu, 2012). 

Zhang et al. controlled the size of nanoparticles by exploiting the pH and temperature responsiveness ofa poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) brush [68]. Briefly, a PDMAEMA bmsh was synthesized onto a polystyrene latex nanoparticle via atom transfer radical polymerization (ATRP). Dynamic light-scattering events indicated that pH changes led to temperature changes in solution, which resulted in an alteration in particle size. This approach could be useful in enzyme immobilization or protein separation. 

Fig. 8 Poly(vmylferrocene) brushes extend upon oxidatirm in hexachloroantimonate solutions of methylene chloride or tetrahydrofuran SI-ATRP surface initiated atom transfer radical polymerization (reprinted with permission from [161]. Copyright 2012 American Chemical Society)...

Jia et al. [125] constructed ionic polymer-coated nanofibrous membranes through grafting poly(ionic hquid) brushes (Scheme 8.12) onto the electrospun Si02 nanofiber surface using atom transfer radical polymerization (ATRP) method. They further demonstrated the potential applications of functionalized membranes as an anion-directed molecular gating system and also a membrane with electroactivity via simple counteranion exchange of the attached poly(ionic hquid) brushes. 

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