Low temperature gas plasma-induced graft polymerization of acrylic acid onto polypropylene film

Low temperature gas plasma-induced graft polymerization of acrylic acid(AAc) onto polypropylene(PP) film was performed.The experimental results showed that 15 minutes' grafting was sufficient enough to decrease the water contact angle(WCA) of PP film from 97° to 32°,which indicated a great improvement in its hydrophilicity.FTIR-ATR and SEM studies confirmed the grafting of AAc onto PP film,which resulted in the formation of many bump-like substances in a size of 1-2 μm.The WCA did not increase significantly even after being treated in the boiling water for 10 min,which indicated that the ageing effect of merely plasma-treated PP film was effectively overcome.After grafting for 15 min at 55 ℃,the degree of grafting and WCA of the grafted sample reached 0.45% and 32°,respectively.These parameters were regarded as optimum grafting conditions.