structures together in order to create new properties intermediate between

the two individual polymer components. Film structure, surface properties,

and stability of immiscible hydroxypropyl cellulose (HPC) polyethylene

glycol (PEG) polymeric blend films were investigated. The effect of

substrate properties on the phase separation behavior of a polymer films has

been investigated. We found that the amplitude of this process may be

modified by a substrate material. This is due to the reduced surface

attraction of HPC for the increased surface coverage by PEG. It was observed

that regime of spinodal decomposition of films could be controlled through

manipulation of key parameters of film formation process. Control of these

parameters result in guided surface morphology where surface roughness, pore

size, and segregation can be predicted and directed