Surface-initiated atom transfer radical

Fig. 3 Schematic illustration of surface-initiated atom transfer radical polymerization...

In a recent report, new nanocomposites of Au NPs and poly(4-vinylpyridine) were obtained through surface-initiated atom-transfer radical polymerization (SI-ATRP). The citrate-stabilized gold nanoparticles were first modified by the disulfide initiator [BrC(CH3)2COO(CH2)iiS]2 for ATRP initiation, and the subsequent polymerization of 4-vinylpyridine occurred on the surface of the gold particles. The assembled Au PVP nanocomposites are pH-responsive because of the pyridyl groups, which are facially protonated and positively charged. The micrographs show Au N Ps of around 15 nm size [92] (Scheme 3.14). 

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... 

As an illustration of the application of these techniques, the surface of poly(ethylene terephthalate) (PET) films has been modified via the grafting of polyacrylamide (PAM) by surface-initiated atom transfer radical polymerization (ATRP) and UV-initiated grafting in order to obtain a film of PET with a hydrophilic surface [15c],... 

Tsujii Y, Ejaz M, Yamamoto S, Fukuda T, Shigeto K, Mibu K, et al. Fabrication of patterned high-density polymer graft surfaces II. Amplification of EB-pattemed initiator monolayer by surface-initiated atom transfer radical polymerization. Polymer 2002 43(13) 3837—41. 

Singh N, Chen Z, Tomer N, Wickramasinghe SR, Soice N, Husson SM. Modification of regenerated cellulose ultrafiltration membranes by surface-initiated atom transfer radical polymerization. J Membr Sci 2008 311(1—2) 225-34. 

Desai SM, Solanky SS, Mandale AB, Rathore K, Singh RP. Controlled grafting of N-iso-propylacrylamide brushes onto self-standing isotactic polypropylene thin films surface initiated atom transfer radical polymerization. Polymer 2003 44(25) 7645—9. 

Huang J, Murata H, Koepsel RR, Russell AJ, Malyjaszewski K. Antibacterial polypropylene via surface-initiated atom transfer radical polymerization. Biomacromolecules 2007 8(5) 1396-9. 

Hu Y, Li JS, Yang WT, Xu FJ. Functionalized polymer film surfaces via surface-initiated atom transfer radical polymerization. Thin Sohd Films 2013 534 325-33. 

Fristrup CJ, Jankova K, Eskimergen R, Bukrinsky JT, Hvilsted S. Protein repellent hydrophilic grafts prepared by surface-initiated atom transfer radical polymerization from polypropylene. Polym Chem 2012 3(1) 198—203. 

Z. Lei and S. Bi, Preparation of polymer nanocomposites of core-shell structure via surface-initiated atom transfer radical polymerizations. Mater. Lett., 61, 3531-3534 (2007). 

Recently, Liu s group also reported the fabrication of thermoresponsive cross-linked hollow poly(A-isopropylacrylamide) (PNIPAM) nanocapsules with controlled shell thickness via the combination of surface-initiated atom transfer radical polymerization (ATRP) and click cross-linking. Cross-linked PNIPAM nanocapsules were fabricated by the click cross-linking of PNIPAM shell layer with a tri-functional molecule, l,l,l-fm(4-(2-propynyloxy) phenyl)ethane. Due to the thermo-responsiveness of PNIPAM, cross-linked PNIPAM nanocapsules exhibit thermo-induced collapse/swelling transitions that make it possible to classify them as nanogels. 

Paripovic D, Klok H-A (2011) Improving the stability in aqueous media of polymer brushes grafted from silicon oxide substrates by surface-initiated atom transfer radical polymerization. Macromol Chem Phys 212 950... 

Surface-Initiated Atom Transfer Radical Polymerization... 

Scheme 5.1 CNT-based macroinitiators for surface-initiating atom transfer radical polymerization (ATRP). ...

Huang, W Baker, G.L. Bruening, M.L. Controlled synthesis of cross-linked ultrathin polymer films by using surface-initiated atom transfer radical polymerization. Angew. Chem. Int. Ed. 2001, 40, 1510-1512. 

Lately, surface-initiated atom transfer radical polymerization (ATRP) has been used to obtain a surface-grafted membrane (Liu et al. 2010). A porous PTFE membrane was treated by the hydrogen plasma and the C-F groups of the modified surface became effective initiators of ATRP. PEG methacrylate or its copolymer with A-isopropylacrylamide was grafted in such a way and the modified membranes showed temperature-responsive and protein repulsion features (Liu et al. 2010). 

Liu, Y.L., Han, C.C., Wei, T.C. and Chang, Y. 2010. Surface-initiated atom transfer radical polymerization from porous poly(tetrafluoroethylene) membrane using the C-F groups as initiators. J. Pohm. Sci. A Pohm. Chem. 48 2076-2083. 

In a recent paper, P(HEMA-co-MOEP) brushes were further functionalized using RGD peptides. The desired outcome was to obtain osteoconductive substrates suitable for bone implant applications. Surface-initiated atom transfer radical copolymerization was used to produce the copolymer brushes. It does not appear that the MOEP was purified before use. MOEP was found to promote matrix mineralization with a concomitant increase with MOEP content. Mineral formation was most pronounced on substrates that presented both phosphate groups and the RGD peptide sequences. 

Morandi G, Heath L, Thielemans W (2009) Cellulose nanocrystals grafted with polystyrene chains through surface-initiated atom transfer radical polymerization (SI-ATRP). Langmuir 25 8280-8286... 

MaUik, A.K. Rahman, M.M. Czaun, M. Takafuji, M. Diara, H. Facile synthesis of high-density poly(octadecyl acrylatej-grafted siUca for reversed-phase high-performance liquid chromatography by surface-initiated atom transfer radical polymerization. J. Chromatogr. A, 2008,1187, 119. 

Kim, J.-B, Bruening, M.L. Baker, G.L. Surface-initiated atom transfer radical polymerization on gold at ambient temperature. J. Am. Chem. Soc. 2000, 122, 7616. 

Recently, surface modification techniques for polymer chains have progressed a great deal with the development of a new polymer synthesis method. In particular, surface-initiated atom transfer radical polymerization (SI-ATRP) is one of the most effective modification methods for preparing a well-defined dense polymer brush structure, or polymer brush, on solid substrates. Thus, a self-oscillating polymer brush prepared by SI-ATRP can be expected to create a novel self-oscillating surface with autonomous function, which will lead to potential applications in transporting systems for nanomaterials of flow control in microfluidics. 

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... 

Ye J, Chen Y, Zhou W, Wang X, Guo Z, Hu Y (2009) Preparation of polyma PbS hybrid nanofibers by surface-initiated atom transfer radical polymerization and acidolysis by H2S. Mater Lett 63 1425-1427... 

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