O uso do plasma de nitrogênio para modificação superficial em membranas de quitosana

Abstract

The treatment by plasma of polymer surfaces has been applied in various fields of study such as biomedical, electronics and textiles. Most of these applications uses plasmas at low pressure and temperature. Due to the versatility of plasma, the result of its interaction with the surface of the polymer changes the physical and chemical properties of these, such as permeability, coefficient of friction, surface energy and chemical properties. Among the polymers that are being modified by plasma has the chitosan. Chitosan membranes were treated in a plasma reactor with a constant pressure of 6 mbar, gas flow of 16 sccm (nitrogen), a current of 0.09 A for 60 minutes. Testing of contact angle, surface tension, roughness and permeation were performed to characterize the treated samples and compare them with the untreated sample. To test the contact angle and surface tension were used three liquids: water, formamide and glycerol. Treated membranes showed higher hydrophilicity and an average roughness (Ra) equal to 5.911nm while the untreated membranes the Ra was 3.426nm The permeation in treated and untreated membrane was constant