Weights solution properties relationship

The dilute solution properties of copolymers are similar to those of the homopolymer. The intrinsic viscosity—molecular weight relationship for a VDC—AN copolymer (9 wt % AN) is [77] = 1.06 x 10 (83). The characteristic ratio is 8.8 for this copolymer. 

Dilute and concentrated solution properties of PBZT and PBZO have been studied [30] in detail by Berry et al. Their research has provided important relationships for the solutions of these polymers such as the response of the viscosity to temperature, shear, polymer concentration, polymer molecular weight and solvent composition. The relationship of intrinsic viscosity to molecular weight has been determined for both PBZT and PBZO [31]. 

Robinson, G., Ross-Murphy, S. B., and Morris, E. R. (1982). Viscosity-molecular weight relationships, intrinsic chain flexibility, and dynamic solution properties of guar galactomannan. Carbohydr. Res. 107 17-32. 

Theoretical treatments on the viscosity of solutions of polymer chains are too numerous to give even a brief summary. Originally their principal objective was to explain the intrinsic viscosity-molecular weight relationship as described in Eq. (5). Now the major interest goes far beyond that and toward a better understanding of the solution properties of polymers. Our brief discussion will be confined only to general terms. The approach... 

Dilute Solution Properties. The rheology of dilute polymer solutions has been used extensively to gain insight into the structure and conformation of polymers in solution (11). The intrinsic viscosity provides a measure of the molecular weight of a polymer through a relationship such as the Mark-Houwink-Sakurada equation. Earlier studies of polyacrylamide (PAM) systems and details of the complexity of the characterization of high-molecular-weight water-soluble systems can be found in references 9, 13, and 14. 

Reprinted from Viscosity - Molecular Weight Relationships, Intrinsic Chain Flexibility, and Dynamic Solution Properties of Guar Galactoman-nan , Copyright, 1982, with permission from Elsevier)... 

Early structural characterization of polymers focused on solution properties and their relationship to molecular weight (Dawkins, 1986 Booth and Price, 1989 Yamakawa, 1971 Flory, 1969). Subsequently spectroscopic and chromatographic techniques were developed, and reviews are widely available (Tanaka, 1991 Campbell and White, 1989 Baldwin and Ver Strate, 1972 Hsu, 2004 Stuart, 2002 Koenig, 1999). This chapter describes various characterization techniques, including discussion of the classical methods of analysis, as well as NMR, SANS, and so on. The main modifications for the fourth edition include the addition of newer methods and results and an update of the references. 

The molecular weights of polymers of this type are difficult to measure because of their unusual solution properties and limited range of solvents. Attempts have been made, however, and the relationship between molecular weight and solution viscosity (the Mark-Houwink equation. 

In the case of evaporation of the solvent, the extruded polymer solution properties inside the spinning zone would vary in relation to the original properties of the solutions taken and would, therefore, correlate with the original concentration and molecular weight of the original polymer solution. Figure 1.8 shows the relationship of nanofiber diameter against the Berry number, which is the product of... 

Wilke and Chang, 1955 (32) studied the diffusivity of both iodine and toluene in alkanes and included in their analysis other systems from the literature. They investigated the influence of solvent properties, such as, viscosity, molar volume, molecular weight and heat of vap>orization and found a linear relationship between Log (Dpg/T) and Logp with a slope of (0.5). They examined also the influence of solute properties, by collecting diffusion data for a variety of solutes in the solvents, water, methanol, ethanol, hexane, toluene and carbon tetrachloride and they observed a linear relationship between Log (Dpg/T) and log V, the slope being (-0.6). They proposed the following equation... 

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