The viscosity of polymers and their concentrated solutions

The results of an extensive study of some dilute solution properties of a series of linear, homogeneous (anionically prepared) polystyrenes (48<10−4M<440) over a wide temperature interval (10°<T<110°C) in decalin and toluene are described The data are used to obtain detailed comparisons among the second virial coefficient A2, the mean‐square molecular radius 〈s2〉, the molecular weight M, and the temperature The empirical correlations thus obtained are compared to theoretical predictions In particular, it is found that A2M½(〈s2〉/M)0−32 and α2=〈s2〉/〈s2〉0 are each single‐valued functions of the interaction parameter z=B(〈s2〉0/M)0−32M½, when B is assumed to have the temperature dependence B=B0[1—(Θ/T)] Certain theoretical predictions for the dependence of A2M½/α3 on z/α3 are found to adequately describe the form of the observed behavior and can be used as the basis for a satisfactory empirical relation The observed dependence of α2 on z is satisfactorily predicted by recent calculations of Flory and Fis

Thermodynamic and Conformational Properties of Polystyrene. I. Light‐Scattering Studies on Dilute Solutions of Linear Polystyrenes

Publisher Summary
This chapter deals with the cohesive energy and the solubility parameter, and explains the correlation of these quantities with chemical structure. The cohesive properties of a polymer find direct expression in its solubility in organic liquids. The cohesive properties of a substance are expressed quantitatively in the cohesive energy. This quantity is closely related to the internal pressure, a parameter appearing in the equation of state of the substance. The solubility of a given polymer in various solvents is largely determined by its chemical structure. Besides the chemical structure, also the physical state of a polymer is important for its solubility properties. Crystalline polymers are relatively insoluble and often dissolve only at temperatures slightly below their crystalline melting points. As a general rule, the solubility decreases as the molar mass of the solute increases. This property can be used to fractionate polymers according to molar mass. This chapter begins by pointing out that the order of solubility of a given solute in a series of solvents is determined by the internal pressures of the solvents. Following this, it introduces the concept of “cohesive energy density,” identifying this quantity with the cohesive energy per unit volume. Finally it provides a comprehensive treatment of this concept and verifies the proposition that the square root of the cohesive energy density is a parameter identifying the behavior of specific solvents.

Cohesive Properties and Solubility

http://web.mit.edu/nnf/publications/GHM163.pdf

Solution spraying of poly(methyl methacrylate) blends to fabricate microtextured, superoleophobic surfaces

The results of an extensive study of the intrinsic viscosity [η] of a series of linear, homogeneous (anionically prepared) polystyrenes (1.9 ∼106. Above this molecular weight the dependence of [η]/[η]0 on z is satisfactorily predicted by recent calculations of Fixman; [η]/[η]0 is not linear in z contrary to other recent suggestions. The failure of the data on lower molecular weight polymers to be a single‐valued function of z is discussed in terms of partial draining effects.

T.G. Fox

Papers

Properties of dilute polymer solutions I—Osmotic and viscometric properties of solutions of conventional polymethyl methacrylate

Properties of dilute polymer solutions IILight scattering and viscometric properties of solutions of conventional polymethyl methacrylate

Properties of dilute polymer solutions III: Intrinsic viscosity/temperature relationships for conventional polymethyl methacrylate