The recently derived general equation for the capacity ratio has been utilized to study the dependence of selectivity and resolution upon mobile phase composition. This equation accounts for differences in molecular size of solutes and solvents, and for the energetic heterogeneity of the adsorbent s
Dependence of modulus and viscosity upon composition for mixtures of polymers. Effects of phase composition and properties of phases
โ Scribed by V.N. Kuleznev; O.L. Mel'nikova; V.D. Klykova
- Publisher
- Elsevier Science
- Year
- 1978
- Tongue
- English
- Weight
- 591 KB
- Volume
- 14
- Category
- Article
- ISSN
- 0014-3057
No coin nor oath required. For personal study only.
โฆ Synopsis
For polymer mixtures with narrow-MMD, the most common types of viscosity-composition and elastic modulus-compositions relations are investigated. It is shown that viscosity anomaly in two-phase polymer mixtures develops, when the polymers have different thermodynamic flexibility of macromolecules. In a polymer mixture solution, viscosity anomaly develops not just above the concentration of phase separation but at substantially higher concentrations, when a single unified entanglement network forms in solution. The viscosity and elastic modulus-composition relation is described by the Pakula-Kryszewski and Kerner equations.
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