Parametre de solubilite d'un polyurethanne de structure definie

The limiting swelling of a polyurethane of well defined structure was investigated in numerous solvents. It was found that the polymer dissolved for a very narrow range of solubility parameter (δ) values. The swelling in various solvent mixtures exhibits a sharp maximum for δ = 9.6±0.2. This value is suggested for δ of the polyurethane. Theoretical evaluations lead to a similar result. It was also found that for N-vinylpyrrolidone, a solvent for the polyurethane, δ is between 9.5 and 11.1.