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Dextran-Based Polycations: Thermodynamic Interaction with Water as Compared With Unsubstituted Dextran, 2 – Flory/Huggins Interaction Parameter

✍ Scribed by Maria Bercea; Marieta Nichifor; John Eckelt; Bernhard A. Wolf

Book ID: 102485160
Publisher: John Wiley and Sons
Year: 2011
Tongue: English
Weight: 343 KB
Volume: 212
Category: Article
ISSN: 1022-1352
DOI: 10.1002/macp.201100197

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✦ Synopsis

Abstract

The Flory‐Huggins interaction parameter χ is determined as a function of volume fraction of polymer φ by vapor‐pressure measurements at 25, 37.5 and 50 °C for five dextran samples that differ in f, the fraction of randomly distributed charged monomer units. The function χ(φ) has a minimum that is shifted towards lower χ values as f increases. The higher the temperature, the more the individual curves fan out. The heats of dilution at high polymer concentrations change from exothermal to endothermal as f increases. The results can be well modeled by an approach accounting explicitly for chain connectivity and conformational changes. A smooth transition of the solution properties upon the random introduction of charged units into dextran is observed.

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📜 SIMILAR VOLUMES

Dextran-Based Polycations: Thermodynamic

Dextran-Based Polycations: Thermodynamic Interaction with Water as Compared With Unsubstituted Dextran, 1 – Volumetric Properties and Light Scattering

✍ Simona Morariu; John Eckelt; Bernhard A. Wolf 📂 Article 📅 2011 🏛 John Wiley and Sons 🌐 English ⚖ 274 KB

## Abstract Dextran and random dextran‐based copolymers containing different molar fractions __f__ of charged units are studied in aqueous solution and in the pure state. The specific volumes of the solutions decrease linearly with increasing weight fraction of the polymer. Extrapolation to the pur