The present invention provides methods of reducing friction on a surface of an apparatus that stores or transports a gas, comprising: (a) contacting the surface either directly or through an intermediate organometallic layer with a fluorinated material in a diluent, wherein the fluorinated material has the following structure: ##STR00001##
wherein A is an oxygen radical or a chemical bond; n is 1 to 20; Y is H, F, C.sub.nH.sub.2n+1 or C.sub.nF.sub.2n+1; X is H or F; b is at least 1, m is 0 to 50, p is 1 to 20, and Z is an acid group or an acid derivative; (b) forming a hydrophobic surface layer on the surface; and (c) introducing the gas into the apparatus.

The present invention provides treated gravel pack screens comprising a metal surface and a hydrophobic surface layer applied thereto, directly or through an intermediate layer. The surface layer comprises a self-assembled monolayer prepared from a fluorinated material having the structure: ##STR00001##
wherein A is an oxygen radical or a chemical bond; n is 1 to 20; Y is H, F, C.sub.nH.sub.2n+1 or C.sub.nF.sub.2n+1; X is H or F; b is at least 1, m is 0 to 50, p is 1 to 20, and Z is an acid group or an acid derivative. Also provided is a method of reducing deposition of a contaminant on a metal surface of a gravel pack screen, comprising: contacting the surface with the above fluorinated material in a diluent, directly or through an intermediate layer; forming a hydrophobic surface layer on the surface; and introducing a fluid through the gravel pack screen.