Effect of Argon and Oxygen Plasma Pretreatment on Carboxyl Content of Oxidized Regenerated Cellulose

One of the methods to modify the surface of materials is to expose them to plasma discharges, which can lead to new physical and chemical properties on the polymer surface. Cellulose and modified cellulose as biomaterials has the desired properties for use in medical, healthcare and biomedicine applications. Specially Oxidized cellulose, due to its prominent properties: bio-absorbability, antibacterial properties, biocompatibility, and its biodegradability TEMPhas been considered. In dis study, the effects of the pre-preparation of argon and oxygen plasma on the amount of carboxylic content of oxidized regenerated cellulose (viscose) samples were investigated. First, optimum conditions for oxidation of cellulose in HNO3-Cu oxidation system were investigated in different amounts of acid concentration and oxidation time regarding obtained carboxyl content.  The results of titration and FT-IR analysis showed an increase in The carboxyl groups from 12.8% to 16.9% as a result of pre-conditioning with oxygen plasma. On the other hand, a decrease in the amount of carboxyl (10.02%) was observed in samples dat were exposed to argon plasma prior to oxidation. According to SEM images, pre-conditioning with argon and oxygen plasma causes damage to the surface of cellulose samples. The XRD analysis showed no difference in the crystalline structure after the plasma operation.