Mark–Houwink–Sakurada constants and dilute solution behavior of heterodisperse poly(acrylamide-co-sodium acrylate) in 0.5M and 1M NaCl

Abstract

SynopsisMark Houwink coefficients and molecular size parameters are presented for 31 unfractionated samples of polyacrylamide and hydrolyzed polyacrylamide in 0.5M and 1M aqueous NaCl.Polymers investigated include polyacrylamide, plus 10, 20, 50, 70, and 100 mol I poly(s0dium acrylate). Their solution characteristics were studied by gel permeation chromatography, intrinsic viscosity, and light scattering techniques. A density function and heterodispersity index was assigned to each polymer sample due to the polydispersity of the molecular weight distributions. This technique improves the intrinsic viscosity-molecular weight correlation for heterodispem commercially synthesized polymer systems. The intrinsic viscosity of these commercial compounds w i l l yield useful estimates of their molecular weight, in spite of their obvious heterogeneity.

Molecular weight and the Mark‐Houwink relation for ultra‐high molecular weight charged polyacrylamide determined using automatic batch mode multi‐angle light scattering

“…When the M w is below 5.3 × 10 6 g mol −1 , Mark‐Houwink constants a = 0.723, K = 1.79 × 10 −4 dL g −1 , which are consistent with literature values that covered the similar MW regions (<∼5 × 10 6 g mol −1 ) (see Table ). When the M w is above 5.3 × 10 6 g mol −1 , Mark‐Houwink constants a = 1.14, K = 2.63 × 10 −7 dL g −1 , are significantly different from those values for the lower MW range.…”

“…According to literature, 34 both constant k and a are insensitive to temperature when a exceeds about 0.70, and they can be used in a ten‐degree range on either side of temperature at which the constants were determined. Since a constants for the 30 mol % APAMs determined in this and a few other work are greater than 0.70, the constants determine in this work are suitable for use at 25–30 °C, at which most IV measurements on polyacrylamides are conducted.…”

Synthesis and solution property of acrylamide-sulfobetaine copolymers

“…As polymer chains change from random coils in θ-solvent to worm-or rod-like rigid conformations, α increases from 0.5 to above 0.8 and generally lies in the range of 0.5-0.8 for flexible chains in dilute solution [66]. α of PAM in 1 M NaCl is 0.72 according to McCarthy [67]. For the PAM8-2DMAPS copolymers, a value of α=0.52 means that the 1 M NaCl solution behaves as a near θ-solvent and the copolymer chains adapt a very slightly extended conformation in the infinite dilute limit in comparison with the unperturbed coils.…”

Amine‐modified poly(vinyl alcohol) as a novel surfactant to modulate size and surface charge of poly(lactide‐co‐glycolide) nanoparticles

“…The solvent employed was an aqueous solution of 1.0 mol L −1 NaCl and intrinsic viscosity was estimated from Huggins and Kraemer plots . For calculation of the viscosity‐average molecular weight, Mark–Houwink–Sakurada parameters reported by McCarthy et al were used.…”