Homogeneity and penetration depth of atmospheric pressure plasma polymerization onto electrospun nanofibrous mats

•Functional plasma polymer was prepared on electrospun polymer nanofibrous mat.•Plasma polymerization run at atmospheric pressure in Ar/maleic anhydride/C2H2 mixture.•Anhydride/carboxyl plasma polymer thin films coated uniformly the polymer nanofibers.•The coating penetrated deep into the nanofibrous mat.