Corrosion Characters in Sulfuric Acid of Polypropylene Films Modified by Maleic Anhydride Plasma

Polypropylene film surfaces were modified by plasma polymerization method of maleic anhydride to improve the surface hydrophilicity.The effects of the plasma power on the surface chemistry and the surface hydrophilicity were investigated by the FT-IR and contact angle methods.The corrosion characters of poly(maleic anhydride) on modified film surfaces in sulfuric acid medium were evaluated.The surface contact angle values of the modified films were decreased to 43°~50° and increased with the increase of plasma power.The corrosion resistance properties of poly(maleic anhydride) of 50W were better than those of 30W in 40% sulfuric acid solution at 110 ℃.The sulfonic groups could be introduced to plasma polymer in sulfric acid solution at higt temperature,the contact angles of modified films were decreased to lower than 30°.