IMPACT OF NITROGEN COLD PLASMA TREATMENT ON FIBERS OF LUFFA CYLINDRICA

An innovative approach of modifying the surface of natural, cellulose rich fibers of luffa cylindrica(LC) using nitrogen (N2) gas cold plasma is discussed in this paper. The cold plasma treatment utilizes ionized gas at low pressure to change the chemical structure and surface roughness of the fiber with an objective of increasing the adhesion between matrix and fiber during fabrication of composite materials using plasma treated fiber. The LC fiber are exposed to N2 cold plasma for exposure time of 20sec at 1kV and 120 sec at 2kV .Before plasma exposure ,the LC fibers are modified by Ca salts so that the fiber can be explored to be used in biomedical terrain. The plasma treated fibers are characterized by XRD, FT-IR and TGA. The mechanism of molecular interaction between LC fiber and cold plasma are discussed in details along with the description of the cold plasma treatment experimental setup. The XRD pattern of plasma treated LC fiber revealed destruction of the glycosidic linkage present in the cellulose of the fiber. The crystallinity index of the LC fiber increases with increase in exposure time. FTIR study indicates presence of amines in the backbone of cellulose chain which is an index of increased reactivity of fiber. Hydrophilicity which is a considerable drawback of natural fiber is got rid of as indicated in TGA curve thus can enhance the fiber-matrix adhesion. Therefore the findings of XRD, TGA and FTIR are encouraging and make the plasma treated LC fiber suitable to be used as reinforcement in synthesis of biodegradable green composites. The plasma treatment on the fiber uses no chemicals, free from water and chemical waste, environment friendly, timesaving and cost effective. Significant statement The present study explores the innovative method of giving cold N2 plasma treatment(fast, free from chemical hazards, environment friendly) to agricultural cellulosic plant fiber with an objective of modifying the fiber surface .The modified fiber can be utilized as reinforcement fillers in fabrication of biodegradable composite materials, green alternatives to synthetic materials.