Polymer brushes grafted

We consider a system consisting of two identical polymer brushes (grafted to two parallel plates) and solvent molecules. The cubic lattice model is employed to represent the mixture of polymer chains and solvent (schematically shown in Fig. 1). Each polymer segment and each solvent molecule occupies one lattice site. The lattice is divided into 2m layers parallel to the plates, numbered from any of the two plates as 1, 2,..., m+ 1,...,2m+1 i,...,2m. Each lattice layer... 

Three main strategies have been successfully developed for the synthesis of cylindrical polymer brushes grafting through, grafting to, and grafting from. Scheme 8 shows the processes for each preparation strategy. 

T. Kawai, K. Saito, K. Sugita and T. Sugo, Extension and Shrinkage of Polymer Brush Grafted onto Porous Membrane Induced by Protein Binding, Macromolecules, 33 (2000) 1306. 

Yun JM, Jung CH, Kim DK, Hwang IT, Choi JH, Ganesan R, et al. Photosensitive polymer brushes grafted onto PTFE film surface for micropatterning of proteins. J Mater Chem 2010 20(10) 2007-12. 

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... 

Ito, Y, Nishi, S., Park, YS. and Imanishi, Y. 1997a. Oxidoreduction-sensitive control of water permeation through a polymer brushes-grafted porous membrane. MacrvmQl gl 30 ... 

Mu B, Shen RP, Liu P (2009) Crosslinked polymeric nanocapsules from polymer brushes grafted silica nanoparticles via surface initiated atom transfer radical polymerization. Colloid SurfB 74 511-515... 

Gao, X. Kucerka, N. Nieh, M. P Katsaras, J. Zhu, S. P Brash, J. L. Sheardown, H. Chain conformation of a new class of PEG-based thermoresponsive polymer brushes grafted on silicon as determined by neutron reflectometry. Langmuir 2009, 25, 10271-10278. 

Patel, A.K. Sharma, P.S. Prasad, B.B. (2009). Electrochemical sensor for uric acid based on a molecularly imprinted polymer brush grafted to tetraethoxysilane derived sol-gel thin film graphite electrode. Materials Science and Engineering C, 29,1545-1553. 

Figure 38 Equilibrium morphologies of six polymer brush-grafted AuNP systems in five...

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. 

Nguyen, A. T., Baggerman, J., Paulusse, J. M. J., Van Rijn, C. J. M., Zuilhof, H. (2011). Stable protein-repellent zwitterionic polymer brushes grafted from silicon nitride. Langmuir, 27, 2587-2594. 

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. 

Graphical representation of the preparation of ferrocene-functionalized polymer brushes grafted on gold nanoparticles via SI-ROMP. (Reprinted with permission from Watson et at. 1999. Hybrid nanoparticles with block copolymer shell structures. Journal of the American Chemical Society 121 (2) 462-463, copyright (1999) American Chemical Society.)... 

On the other hand, cationic polymer brushes grafted on PET surfaces could prevent microbial infection in industrial and medical fields, such as alkyl pyridinium or quaternary ammonium moieties. Gen et al. grafted copolymerized with 4-vinylpyridine (4VP) and subsequently quaternized with hexylbromide [53,54], and N-hexyl-N -(4-vinylbenzyl)-4,4 -bipyridinium bromide chloride (HVV) [55] onto PET films for enhancing antibacterial properties. The PET films were pretreated by argon plasma to form surface... 

Probably the first notion of polymer brushes grafted inside pores was given by Sevick [6] in the mid 1990s in relation to the potential fabrication of pressure-sensitive microvalves. Essentially it was proposed that adsorbed polymer brushes on the inner surface of pores might sense the solvent flow through the pores due to a pressure difference and then respond by swelling. This response that actively changes the pore cross section is an... 

E. M. Sevick. Shear swelling of polymer brushes grafted onto convex and concave surfaces. Macromolecules. 29(21) 6952-6958,1996. 

Using electrochemistry to probe the transport of Ox/Red within polymer brushes grafted onto substrates, (a) Direct electrochemical measurement at a grafted electrode by chrono-amperometry (CA), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) represented by their respective waveform, (b) Indirect measurement by SECM. The overall process is decomposed in (a) into the subsequent steps (from top to bottom) solution diffusion, partition at the solution-polymer brush interface, diffusion in the brush, and electron transfer at the electrode. (Adapted from Matrab, T., et al., ChemPhysChem, 11,670-682,2010.)... 

In this approach, a controlled polymerization reaction is used to amplify chemical defects on a surface, and therefore to access indirectly the chemical reactivity of a functional surface. This strategy has been used to interrogate the reactivity of thin assembled layers of different ATRP polymerization initiators. The principle relies on the ability of the selected experimental conditions of ATRP polymerization, to grow polymer brushes of thicknesses proportional to the polymer molecular mass, M . Then, for surfaces presenting different densities of polymerization initiator, the growth of polymer brushes of similar mass, M, yields polymer thickness, e, proportional to the polymer brush grafting density, Op, according to Equation 8.8 ... 

Modulation of the driving force of the debromination efficiency, (a) Schematic representation of the effect of the driving force of Equation 8.9 on the polymer brush conformation within and outside patterns, (b) Experimental variations of the polymer brush grafting density, Op, in the patterns, with E% the standard reduction potential of the reducing etchant (driving force of the transformation). (Adapted from Slim, C., et al., Chem. Mater., 20, 6677-6685,2008.)... 

Such lithographic procedure allows for the precise control of the initiator grafting density at the micrometer scale and allows, in principle, the patterning of surfaces with domains presenting controlled polymer brush grafting densities and therefore controlled thicknesses. It is in principle transposable to recently reported ways to electrochemically mediate ATRP... 

Polymer brushes are ultrathin polymer coatings that consist of polymer chains with one end covalently tethered to a substrate, i.e., a surface either needing modification or serving as a support [20]. There are two methods to synthesize polymer brushes grafting to and grafting from. Grafting to techniques employ prefabricated, end-functionalized polymer chains that are... 

Tagit and coworkers developed surfaces which can act as nano-thermometers using quantum dots (QDs) attached to PNIPAM polymer brushes grafted onto a gold substrate. The luminescence of these QDs could be quenched by increasing the temperature above the LCST of PNIPAM, and recovered by decreasing it (Tagit, 2009). 

Fig. 16.3 Illustration showing relationship between polymer brush grafting density and chain length...

Pei Y, Travas-Sejdic J, Williams DE (2012) Reversible electrochemical switching of polymer brushes grafted onto conducting polymer films. Langmuir 28 8072-8083... 

Li CZ, Benicewicz BC (2005) Synthesis of well-defined polymer brushes grafted onto silica nanoparticles via surface reversible addition-fragmentation chain transfer polymerization. Macromolecules 38 5929-5936... 

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