Miscibility of isotactic polypropylene in n-pentane and n-pentane plus carbon dioxide mixtures at high pressures

Demixing pressures for solutions of isotactic polypropylene (M(w)=216 000; M(w)/M(n)=7.2) in n-pentane have been determined for polymer concentrations of 1, 3, 5, 10, 15 and 30 mass% in the temperature range from about 410 to 480 K. Isotactic polypropylene is completely miscible in n-pentane at these concentrations at pressures above about 10 MPa. Limited data are also presented for miscibility in binary mixtures of n-pentane+carbon dioxide. In the presence of carbon dioxide, higher pressures are required for complete miscibility. (C) 1998 Elsevier Science B.V.