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The adsorption behaviour of functionalized polystyrene-block-polybutadiene diblock copolymers, P(S-b-B), and polybutadiene-block-polystyrene-block-polybutadiene triblock copolymers, P(B-b-S-b-B), from dilute solutions in toluene onto silicon wafers was investigated by means of null-ellipsometry. Polar 4-(3,5-dioxo-1,2,4-triazolidin-4-yl) benzoic acid groups (urazole groups) were attached randomly...
Inverse gas chromatography has been used for the determination of the glass transition temperatures of amorphous polymers and the thermodynamic functions for adsorption of n-alkanes (C 7 to C 10 ), n-butanol, di-n-butyl ether and 1,4-dioxane in the Henry region onto the surface of polystyrene, styrene-nonyl methacrylate (4 : 1) copolymer, and styrene-maleic anhydride-methacrylic...
Attachment of the peroxide initiator of radical polymerization to the surface of various oxides due to the adsorption of reactive copolymers of peroxide monomer and maleic anhydride (PM-MA) was performed. Plateau adsorption amount of PM-MA depend mainly on the nature of the solvent. It was found that adsorption is irreversible with respect to the solvent. Measuring the exchange between the polymer...
Lattice model dendrimers interacting with an adsorbing planar surface are studied by computer simulation, where G is the number of generations of the dendrimer and A is the interaction strength. With increasing A, dendrimers are observed to spread out and flatten down on the surface, as expected. In certain regions ofG-A space, two competing configurational states, S 2 and S 3 , are...
Adsorption properties of polybutadiene on carbon black aggregates are investigated from several experimental approaches: weighing, n.m.r. of protons attached to chains, and swelling of mixtures, induced by good solvents of the polymer. The observed apparent law of polymer adsorption is shown both experimentally and theoretically to obey a master curve obtained by using the reduced variable defined...
Polyethylene terephthalate/polyoxyethylene terephthalate (PET/POET) water-soluble polymers are effective surface modifiers of polyester-containing textiles and exhibit surface activity in aqueous solutions. Adsorption of a PET/POET polymer on fabric was studied using ultraviolet-visible (u.v.-vis) and fluorescence spectroscopy. Aqueous PET/POET solutions exhibit two distinct fluorescent emission...
The adsorption of a single chain on structured surfaces is investigated using the bond-fluctuation model. The different surfaces were a flat, a stick-like, a pyramidal surface and a surface with square holes. The adsorption starts at about the same temperature for all surface structures, therefore denoted as the adsorption temperature. The rate for further adsorption with decreasing temperature...
The spin-label method has been used to study the structure and molecular motion of polystyrene chains adsorbed on porous silica. Spin-labelled polystyrene (PS) with a narrow molecular weight distribution, havingM w (weight average molecular weight) = 1.9 10 5 was adsorbed on the surface of porous silica with two different pore diameters, 28.5 nm (MB-300) and 81.3 nm (MB-800), in...
N.m.r. relaxation and diffusion studies of the adsorption of polydimethylsiloxane polymers on silicas have been carried out as a function of particle concentration and polymer molecular weight. The structure of the adsorbed layer can be rationalized by a three-state model comprising bound polymer, polymer entangled or restricted by the adsorbed layer and free bulk polymer. In particular, n.m.r. relaxation...
The spin-label method was used to study the structure and molecular motion of polystyrene chains adsorbed on three different porous silica surfaces, in order to examine the effect of surface geometry on the conformational structure. Three kinds of spin-labelled polystyrene (PS) samples with narrow molecular weight distributions, having weight-average molecular weight (MW) = 2.98 × 103, 96.4 × 103,...
Electron spin resonance (e.s.r.) spectroscopy of spin-labelled poly(ethylene oxide) (SL-PEO) tethered on silica was studied to characterize the conformation and local dynamics of the chain end. Non-labelled polysterene (PS) with narrow molecular weight distributions, having weight-average molecular weights (M w ) of 9.64 10 4 (PS-96) and 3.84 10 5 (PS-384), were adsorbed...
The spin-label method was used to study the structure and molecular motion of polystyrene (PS) chains adsorbed on a silica-tethered poly(ethylene oxide) (PEO). Spin-labelled polystyrene with a narrow molecular weight distribution, having a weight-average molecular weight (< w ) of 9.64 10 4 , was adsorbed on the surface of the silica-tethered PEO with various grafting ratio...
Recent experimental data of Cohen Addad and Frebourg on the adsorption of polybutadiene chains on the ISAF carbon black from bulk were compared with the polymer-filler gel formation theory. A very good agreement was obtained and the resulting parameter-values were similar to those recently determined for the SBR-ISAF black system. This lends support to the model upon which the theory is based: random...
The kinetics of adsorption of poly(dimethylsiloxane) (PDMS) on silica particles was studied. A theoretical model was developed and fitted to different sets of experimental data to investigate the dependence of model parameters upon polymer and filler characteristics. In the model, the formation of bound polymer was pictured as a second-order reaction process with a rate proportional to both the...
The effect of chain architecture of graft copolymer on the structure of an adsorbed layer on a surface is investigated using an off-lattice Monte Carlo simulation method. The graft copolymers used for the simulation have the same composition but different chain architecture. The simulation results show that the layer thickness of multi-chains adsorbed onto the surface first decreases with increasing...
Self-assembled films of Poly(o-ethoxyaniline) (POEA) doped with HCl alternated with sulfonated lignin (SL) were successfully produced under different pHs and their kinetics of formation studied. The adsorption at lower pHs is faster due to the greater electrostatic attraction between the POEA and the SL covered substrate, but a lower amount of POEA is deposited due to charge repulsion of additional...
Four hyaluronan based hydrogels with different cross-linking agents were synthesised. Compounds with an increasing hydrophobic character and length as spacer arms were chosen, i.e. O,O'-bis(2 aminopropyl)polyethylen glicol, 1.3 diaminopropane, 1.6 diaminohexane, and 1.12 diaminedodecane. The cross-linking reaction involved 50% of the carboxylate groups present in the hyaluronan macromolecule chain...
The adsorption of gelatin chains on polystyrene (PS) latex nanoparticles was investigated by a combination of static and dynamic laser light scattering (LLS). The average mass of gelatin adsorbed on each nanoparticle (m adsorbed ) was calculated from the absolute scattered intensity, while the hydrodynamic volume (V shell ) of...
We report thermodynamic and conformational properties of collapsed polymer globules in a poor solvent close to adsorbing and non-adsorbing surfaces containing a cylindrical pore that is either smaller or larger than the coil size in bulk solution. Configurational Bias Monte Carlo simulations at infinite dilution were used for this purpose. We find that above the critical adsorption transition changing...
The complexation agent 2[-bis-(pyridylmethyl) aminomethyl]-4-methyl-6-formyl-phenol (HL) was immobilized in chitosan in order to obtain a new adsorbent material to be employed in studies on adsorption and pre-concentration of Cu(II). The chitosan modified by the complexation agent was characterized by infrared spectroscopy, DSC and TGA. The studies were conducted as a function of the pH of the medium...
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