POLY(AMMONIOALKANESULFONATE) BLENDS WITH POLAR ORGANIC-SPECIES AND ALKALI-METAL SALTS - STRUCTURE, GLASS-TRANSITION AND IONIC-CONDUCTIVITY

Because the dipole moment of its zwitterionic side group is very high (mu similar to 23 D), -diethyl-N-(5-methacryloyoxy-3-oxopentyl)-ammoni o) propanesulfonate] affords a unique polar host matrix possessing a s trong solvation power towards a variety of polar or ionic guest specie s. Water, glycerol, liquid ethylammonium nitrate, triethylammoniopropa nesulfonate are all good plasticizers with a fairly similar efficiency of Delta T-g similar to -2 degrees C/mol% of additive, while a dizwit terion behaves as a weak antiplasticizer. The stoichiometric blends of the polyzwitterion with alkali metal salts of low enough lattice ener gy such as thiocyanates, trifuoromethanesulfonates, iodides, perchlora tes, tetrafluoro or tetraphenylborates, are amorphous systems showing a single glass transition, with plasticization or anf antiplasticizati on effects depending on the salt nature. Microphase separation systema tically occurs in these binary systems but long-range order is observe d only in some cases, with development of lamellar (I-) or hexagonal ( SCN-) structures. Conductivity increases and the dielectric constant o f the material decreases as salt is added. The activation energies of the conductivity are not strongly affected either by the state of the material, glassy or viscoelastic, or by the salt nature. (C) 1997 by J ohn Wiley & Sons, Ltd.