Continuous fractionation of poly[(dimethylimino)decamethylene bromide] and molecular weight dependence of the glass transition

✍ Scribed by Klaus Schultes; B. A. Wolf; Wolfgang H. Meyer; Gerhard Wegner

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 495 KB
• Volume: 196
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.1995.021960403

✦ Synopsis

30 g of the ionene poly[(dimethylimino)decamethylene bromide] were fractionated by a continuous counter-current extraction method (CPF) using ethylene glycol monoethyl ether as the solvent and diisopropyl ether as the non-solvent component. The efficiency of the separation was checked by viscometry and gel-permeation chromatography (GPC) measurements. Eight fractions of different molar mass were prepared for differential scanning calorimetry (DSC) experiments. With bromide as counter-ion, the glass transition temperature of the ionene increases from ca. 60 to 85 "C as the intrinsic viscosity of this material (in 0,4 M aqueous solutions of KBr at 25 "C) rises from ca. 14 to 22 mL/g. When bromide is replaced by tetrafluoroborate, the glass transition temperature remains almost constant at ca. 60 "C, irrespective of the molar mass of the ionene.