Ap. Safronov et al., THERMODYNAMICS OF DISSOLUTION OF POLYACRY LIC-ACID IN DONOR AND ACCEPTOR SOLVENTS, Vysokomolekularnye soedinenia. Seria A, 38(5), 1996, pp. 900-904
Dissolution of PAA in various donor and acceptor solvents was studied
at 273-423 K. A phase diagram with LCST was obtained for PAA-THF syste
m. Mean specific enthalpy of mixing and partial excess enthalpy of the
solvent were determined by calorimetry for the solutions of PAA in wa
ter, the acceptor solvent (butanol), or the donor solvent (DMF), over
the entire range of compositions and at different temperatures. Simila
r data were also obtained for aqueous solutions of poly(methacrylic ac
id) as the closest PAA homolog. PAA more readily interacts with the do
nor compounds than with the acceptor ones. In contract to the other so
lutions studied, the PAA-water system is characterized by abnormal ext
rema in the concentration dependences of the partial excess enthalpy o
f water, The results are discussed in terms of specific features of so
lvation and association processes in PAA solutions.