Polyelectrolytes-Polymethacrylic Acid

The humates present in soil are polyelectrolytes and bear some similarity to polyacrylic acid and polymethacrylic acid (49, 50). The molecular weight distribution for the humates is considerable fulvic acid fractions of 1,000 daltons have been isolated (51) while humic acid molecular weights obtained by gel chromatography are in the range 17,000 to 100,000 daltons according to the type of soil from which it was extracted (52). However, ultracentrifugation analysis indicates a molecular range of 2,000 to 1,500,000 daltons for humic acids (55). 

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. 

Polydectrolytes Polyacrylic acid, -(CH2-CH-COOH) -. At pH > 5, ionisation of the carboxylic acid groups occurs forming an anionic polyelectrolyte. Polyacrylic acid/polymethacrylic acid, (CH2-CH-COO ) - (CH2-C (CH3)-COO ). Naphthalene formaldehyde sulphonated condensates, Hgnosulphonates. 

In this chapter, approaches to estimates of (1) the polyelectrolyte (electrostatic) effect, (2) the hydrophobicity/hydrophilicity effect, and (3) the multicoordination effect, specified for metal ion/polyelectrolyte systems are described. As weak acidic polyelectrolytes, polyacrylic acid, PAA, as well as polymethacrylic acid, PMA, are exemplified as an example of weak basic polyelectrolyte, poI y(/V-vinyI i m idazoIc), PVIm, is chosen all the chemical structures of the polymer ligands are illustrated in Figure 1. Precise poten-tiometric titration studies by the use of a glass electrode as well as respective metal ion selective electrodes have been performed for the complexation equilibrium analyses. All the equilibrium constants reported in this chapter were obtained at 298 K unless otherwise stated. 

Sajeesh, S., Sharma, C.P. Novel pH responsive polymethacrylic acid-chitosan-polyethylene glycol nanoparticles for oral peptide delivery. J. Biomed. Mater. Res. Appl. Biomater., 76B, 298, 2006. Sajeesh, S., Sharma C.P. Novel polyelectrolyte complex microparticles based on polymethacrylic acid-polyethylene glycol for oral peptide delivery. J. Biomater. Sci. Polym. Ed., 18,1125, 2007. 

PPG-5 lanolin alcohol ether PPG-20 lanolin alcohol ether PPG-2 laurate PPG-2 oleate PPG-2 stearate dispersant, polyelectrolyte 2-Hydroxy 3-methacryl oxypropyl trimoniumchloride dispersant, polymerization C13-15 pareth-30 Polymethacrylic acid Polysorbate 80 Polyvinyl alcohol (partially hydrolyzed) dispersant, polymers... 

Aggregation phenomena are observable when cationic dyes are bound to anionic polyelectrolytes, such as polyacryHc acid (PAA), polymethacrylic acid (PMA), or polystyrene sulfonate (PSS). Of is strongly... 

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