Optimization of the mechanical properties and water-vapor transmission properties of free films of hydroxypropylmethylcellulose.

Free films of hydroxypropylmethylcellulose were prepared by a spraying technique. Methocel E5 and Methocel E15 were used in varying proportions in the preparation of films. The free films were studied for their mechanical properties and moisture permeability characteristics. A 2(2) factorial design was used to quantitate the effect of each polymer on the tensile strength and permeability constant of the films.