Hydrodynamic properties of molecules of polyvinylpyrrolidone as shown by sedimentation-diffusion analysis and viscometry

Effect of Centrifugal Field upon Hydrodynamic Characteristics of Fullerene C60and Poly(N-vinylpyrrolidone) Complex in Aqueous Solutions

“…[29,30] The experimental points obtained for PVP-C 60 at different n are in surprising agreement with the data obtained by different authors for homological sets of PVP in aqueous solutions ( Figure 6). [25,36,37] The superscript (3b À 1)= (1 À b) of Equation (6) for the PVP-C 60 complex becomes 1.1-1.5 according to our estimation. Supposing that Equations (5) and (6) are both true for PVP-C 60 , we can estimate superscript 1 À b ¼ (0.45-0.50) for Equation (5).…”

“…For example, the values of S ¼ 2.4 Â 10 À13 s at n ¼ 55000 rpm and S ¼ 2.5 Â 10 À13 s at n ¼ 18000 rpm were obtained for the PVP sample with M SD ¼ 180000 g=mol at solution concentration c ¼ 0.07 Â 10 2 g=cm 3 . This suggests that the change of hydrostatic pressure in the sedimentation from the articles [25], [37], [36] respectively. 212 cell does not directly influence the sedimentation coefficient of the PVP-C 60 aqueous solution.…”

“…On this basis, it was possible to evaluate the MM of the PVP-C 60 complex at different rotor speeds by taking the equations that are true for PVP homologues obtained by various researchers. [25,36,37] The equations used for the calculations are given in Table II, which also shows the intervals of MM and sedimentation constant S 0 . It is 214 E. Tarabukina et al significant that all the mentioned relations were obtained for rather wide MM and, correspondingly, S 0 ranges.…”

“…The obtained Figure 6. Logarithmic dependence of concentration coefficient k s vs. sedimentation coefficient at infinite dilution S 0 for PVP-C 60 and PVP [25,36,37] aqueous solutions. expression seems to fit best the equation from Tarabukina [36] where the subscript 1 À b ¼ 0.5.…”

Synthesis of Water-Soluble Copolymers of N-vinylpyrrolidone with N-vinyldithiocarbamate as Multidentate Polymeric Chelation Systems and Their Complexes with Indium and Gallium

“…It should be noted that monomeric units inside the polymeric chain in initial copolymers VP–VFA have statistic distribution [ 63 ]. Consequently, the statistic character of the VP–VDTC copolymerand irregular arrangement of M(DTC) 3 fragments inside polymeric coil are also expected.…”