ConclusionA single step method to improve surface hydrophobicityof polyurethane (PU) synthetic leather is proposed. Silicon-based precursor was applied for deposition of PU syntheticleather. The silicon-based precursor, TMS, was used togenerate hydrophobic surface on polyurethane synthetic leathersurface by means of atmospheric pressure plasma (APP).Low flow rate of carrier gas facilitated the deposition ofsilicon compounds. Sufficient discharge power is required toinitiate the deposition of TMS without any degradation ofsynthetic leather. Under the optimum combination of theexperimental parameters (flow rate of helium=7.5 LPM;discharge power=50W), a hydrophobic surface was achievedwith static contact angle=94±2o whereas contact angle of theuntreated sample was 80±2o . SEM and FTIR results confirmthat silicon compounds were successfully deposited on thesample surface. Water resistance was improved with en-hancement of surface hydrophobicity. In addition, thehydrophobic surface seems to be robust and stable in time,without hydrophilic recovery 30 days after the APP treatment.