Polyacrylic acid intrinsic viscosity

As early as 1951, Flory and Osterheld [18] could show that partially ionized polyacrylic acid in aqueous solution of an inert salt shrinks in size if the concentration of the inert salt is increased. This shrinking process can be pushed towards the unperturbed dimensions of the NaPA chains. Known from neutral polymers as 0-state, it is reached for fully ionized NaPA [50] at T=15 °C and 1.5 M KBr. In several papers, the dependence of the intrinsic viscosity was investigated as a function of the molar mass [51]. Data were... 

FIG. 3 Variation of the intrinsic viscosity of long alkyl-modified polyacrylic acids as a function of the concentration of bovine serum albumin in the solvent. Solvent used for dilutions 30 mM borate buffer pH 9 and protein (top curves) or same buffer plus 0.3 M NaCl and protein (bottom curves). Black circles polymer modified with 4 mol% of C18 side groups squares polymer modified with 3 mol% of C12 groups cross-circles unmodified poly (sodium acrylate). (Reprinted with permission from Ref. 33. Copyright 1998 American Chemical Society.)... 

Materials. Two samples of polyacrylic acid, PAA-1 (4) and PAA-2, were obtained as gifts from S. C. Johnson Company. Their degrees of polymerization were 3090 and 4420, respectively, as calculated from the intrinsic viscosities of their sodium salts in 0.102V NaBr at 15°C using the appropriate relation of Takahashi and Nagasawa (5). The samples of the hydrolyzed copolymers of maleic anhydride witn ethylene (HEMA) and with methyl vinyl ether (HVMEMA) have been described previously (4). 

Figure 4. Effects of hound silver and hydrogen ions on the intrinsic viscosity of the TMA salt of polyacrylic acid in 0.2M TMANOs at 30°C. The abscissa 0totai denotes the sum of 0H and 0Ag. (O) silver ion bound to PAA-2 initially at a — 0.910 (D) hydrogen ion bound to PAA-2 initially...

Flory, P.J. and Osterheld, J.E., Intrinsic viscosities of polyelectrolytes polyacrylic acid, /. Phys. Chem., 58, 653, 1954. 

The chemical composition, dimensions and the molecular parameters of four dental acrylic polymer materials and two polyacrylic acids of different molec.wt. used as model compounds were studied by NMR and IR spectroscopies, GPC, intrinsic viscosity and light scattering measurements. Two of the dental polymers were shown to be mainly polyacrylic acid, while one showed the peak pattern for an acrylic acid/methyl acrylate copolymer of about 2 1 composition and one was an oligomer derived from 2-hydroxyethyl methacrylate. The steric hindrance parameter, molecular stiffness and second virial coefficient were calculated using different thermodynamic models. The Flory-Fox-Shafgagen and the Stockmayer-Fixman models fitted the experimental data reasonably well and could be use to describe the molecular parameters of the acrylic polymers. 18 refs. (7th International Conference on Polymer Characterization (POLYCHAR-7), Denton, Texas, USA, Jan. 1999)... 

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