[The influence of plasticizers on the permeability of polymethacrylate films (Eudragit RS)]

Pellets with pholedrine sulphate are coated by means of a fluid-bed process with polymethacrylates and increasing portions of plasticizers. The addition of PEG 6000 increased the film permeability. On the other hand triacetin effected no change and dibuthyl phthalate decreased the permeability in relation to films without plasticizers. When the films were contacted 8 h with phosphate buffer (pH = 7,4) PEG could not be detected and triacetin film contents was reduced to about 30%. Unlike that the portion of dibuthyl phthalate decreased insignificantly.