Organization of the copolymer obtained from perfluoroalkylethylacrylate and acrylic acid/ester (FCPn, n = 8) and its spreading characteristics have been studied in Langmuir films at the air/water interface using the surface pressure-molecular area (pi-A) and surface potential-molecular area (AV-A) isotherms. Influence of additives in the interfacial organization and spreading characteristics contributing to significant changes in wetting and adhesion proper-ties of the copolymer film was studied using three types of mixed monolayers with FCP: polar, nonpolar, and amphiphilic. The polar additives such as 1,4 dioxane or alcohols did not show any effect on the spreading behavior of FCP. Only octadecane (OD) and chloroparaffin (CP) among the nonpolar additives in the surface active class change the organization of the polymer at the air/water interface while octadecane alone changes the interfacial energy drastically. An estimate of the compressional moduli for the pure polymer and the mixed films showed that the presence of octadecane in FCP makes the film more elastic. However there is a critical fraction of OD in the mixture beyond which a phase transition takes place.