Poly inhomogeneity

A great variety of suitable polymers is accessible by polymerization of vinylic monomers, or by reaction of alcohols or amines with functionalized polymers such as chloromethylat polystyrene or methacryloylchloride. The functionality in the polymer may also a ligand which can bind transition metal complexes. Examples are poly-4-vinylpyridine and triphenylphosphine modified polymers. In all cases of reactively functionalized polymers, the loading with redox active species may also occur after film formation on the electrode surface but it was recognized that such a procedure may lead to inhomogeneous distribution of redox centers in the film... 

Kobashi, M. Takeuchi, H. 1998. Inhomogeneity of spin-coated and cast non-regioregular poly(3-hexylthiophene) films. Structures and electrical and photophysical properties. Macromolecules 31 7273-7278. 

Another study by means of light scattering (42) showed the formation of inhomogeneous networks in the case of 5 % poly (vinyl alcohol) solutions... 

All three elements can scarcely be identified from impedance spectra of systems with adsorption for example, in many cases the adsorption resistance is masked by the diffusional element. In addition, whenever electrodes of inhomogeneous surfaces (e.g., poly crystalline electrodes) are measured, the resistance-diffusional element - capacitance terms of the adsorption impedance are smeared out yielding a CPE-like impedance. 

Network structure and its size inhomogeneity of poly(methyl methacrylate) (PMMA) gels through diffusional behaviour of probe PSs with different molecular weights... 

The pronounced dependence of the Kerr constant on molecular weight observed for poly(vinyl chloride) and poly(vinyl bromide) solutions appears to be due to their molecular inhomogeneity. The presence of agpegates in solutions of these two polymers has often been detected experimentally - . ... 

The eosine PEF (Fig. 2a, spectrum 1) is accompanied by 2 nm short wavelength shift. The half width (HW) of eosine-poly-L-lysine PEF band (Fig. 2a, spectrum 1) is equal to 30 nm. That corresponds to HW for eosine fluorescence in the aqueous solution (Fig. lb, spectrum 3). It means that eosine-poly-L-lysine PEF band does not undergo the considerable Inhomogeneous broadening due to heterogeneity of the surrounding between two PSFs. 

Inhomogeneous gold polycrystallites with compact structure and a broad range of orientations were formed after 45 min of ultrasonic treatment in a home-developed sonoreactor at the constant temperature. Sonication for additional 40 min recrystallized highly monodisperse platinum nanoparticles with smaller size. The fastest catalysis was enabled by platinum nanoparticles after sonication in the poly vinyl pyrrolidone solution for one hour, while the lowest activity was found for particles after the ultrasonic treatment for 20 min in the ethylene glycol solution. Amorphous and polycrystalline platinum nanoparticles before and after sonication in water have similar catalytic efficiencies. 

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