– The combination of two techniques (Small Angle X-ray Scattering and Atomic Force Microscopy) has allowed us to measure in reciprocal and real space the correlation length ξ of salt-free aqueous solutions of highly charged hydrophobic polyelectrolyte as a function of the polymer concentration Cp, charge fraction f and chain length N . Contrary to the classical behaviour of hydrophilic polyelec...

the purpose of this study was comparison of applicability of tertiary treatment of tehran domestic sewage with organic and inorganic coagulants or a combination of them. the far test procedure was applied utilizing: alum, polyelectrolyte wt 2600, anionic polyelectorlyte wt 3000, and nonionic polyelctrolyte wt 2690 as organic coagulants (products of calgon). the combination of lime with each of ...

Adsorbed layers of polyelectrolytes have been studied with atomic force microscopy (AFM) and the interferometric surface force apparatus (SFA). Particular emphasis was put on determining the effect of the polyelectrolyte charge density on surface topography, and the effect of the polyelectrolyte coating on the adhesive properties. The AFM was employed to image individual polymer chains at low a...

Michal Borkovec, Ger J. M. Koper Email. [email protected], [email protected] September 15, 2013 Direct link www.colloid.ch/polyelectrolytes In aqueous solutions, bases bind protons, while acids dissociate them. For weak acids and bases, these protonation reactions occur in the intermediate pH range. Dealing with monoprotic or diprotic acids and bases, the corresponding binding isoth...

We review recent experiments on the interaction of proteins with anionic polyelectrolytes in aqueous solution. Data from the literature demonstrate that proteins can form soluble complexes with linear polyelectrolytes even on the "wrong side" of the isoelectric point, that is, for pH values above the isoelectric point of the proteins under which the polyelectrolytes and the proteins are like-ch...

We present the electrostatic complexation between polyelectrolytes and charged nanoparticles. The nanoparticles in solution are γ-Fe2O3 (maghemite) spheres with 8.3 nm diameter and anionic surface charges. The complexation was monitored using three different formulation pathways such as direct mixing, dilution, and dialysis. In the first process, the hybrids were obtained by mixing stock soluti...

The formation of polydimethylsiloxanes (PDMSs)-based layer-by-layer multilayer ultrathin films on charged surfaces prepared from water and phosphate buffer solutions has been investigated. The multilayer films prepared under these conditions showed different surface roughness. Nanoscale islands and network structures were observed homogeneously on the multilayer film prepared from pure water so...

PAMAM dendrimers are used as a model system to investigate the effects of counterion condensation and the effective charge for spherical polyelectrolytes. Because of their amino groups, PAMAM dendrimers are weak polyelectrolytes. Lowering the pH results in an increasing protonation of the amino groups which is monitored via the proton chemical shifts of the adjacent CH2 groups. The effective ch...

The processing of a polyelectrolyte (whose functionality is derived from its ionized functional groups) into a nanofiber may improve its functionality and yield multiple functionalities. However, the electrospinning of nanofibers from polyelectrolytes is imperfect because polyelectrolytes differ considerably from neutral polymers in their rheological properties. In our study, we attempt to solv...