Brush quaternized

In a first example, for a densely grafted PEL brush system positively charged quaternized poly-4-vinylpyridine brushes have been prepared by following a two step approach [2, 63, 64, 66]. In the first step a neutral poly-4-vinylpyridine monolayer is prepared and, subsequently, charges are introduced by a second, polymer-analogous quaternization step. The grafting density of the parental neutral brush is adjusted by varying the polymerization time (Fig. 12) [63, 64]. The substrates were planar silicon substrates in... 

Fig. 13 (above) Waveguide-spectra (p-polarization) of a 490 nm thick PVP brush on a LaSFN9/Au/SiOx substrate, and the same sample at a constant relative humidity of 70% after quaternization with methyl iodide (MePVP, thickness 870 nm) (below) FTIR detail spectrum of a PVP brush attached to both sides of a silicon wafer, and the same sample after the polymer-analogous quaternization... 

In the following text we focus on cylindrical brushes prepared by polymerization of macromonomers, in particular on two systems. First, cylindrical brushes consisting of poly-2-vinylpyridine side chains and a poly-methacrylic main chain are discussed these were converted into cationic polyelectrolyte brushes by quaternization of the pyridine units by alkyl halides. The second system comprises sulfonated anionic cylindrical brushes, i.e. polymacromonomers with polystyrene side and main chains and polymacromonomers with polymethacrylic main and polymethacrylic acid side chains. 

Table 6 Light-scattering and IR characterization of cylindrical polyelectrolyte brushes prepared by quaternization of PVP brushes...

Depending on the hydrophobicity of the quaternization agent the polyelectrolyte brushes start to aggregate at higher salt concentrations and eventually precipitate. This aggregation has been observed in situ by AFM for sample PM-PVP21-Bz80 [125]. 

The PDMAEMA stars are weak cationic polyelectrolytes. But they can be easily transformed into strong cationic polyelectrolytes poly [2-(methacryloyloxy)ethyl] trimethylammonium iodide] (PMETAI) stars by quaternization with methyl iodide. Asymmetric field flow fractionation (AFFF) measurements showed that the silsesquioxane core remained intact. The PMETAI brushes were also subjected to... 

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... 

Liu, X., Zhang, H., Tian, Z.C., Sen, A., AUcock, H.R. Preparation of quaternized organic-inorganic hybrid brush polyphosphazene-co-poly 2-(dimethylamino)ethyl methacrylate electrospun fibers and their antibacterial properties. Polym. Chem. 3(8), 2082-2091 (2012). doi 10.1039/c2py20170d... 

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