Cotton Knits Atmospheric Pressure Air Plasma Pre-treatment Process

In this thesis,cotton knitting fabric pretreatment technologies by using an atmospheric pressure plasma treatment with air were reviewed.The present situation and development of plasma and their using technologies were also studied.The principles of plasma,the effect factors of the plasma were discussed.The structure and chemistry composition of the cotton were involved.On this basis,detailed discussion on the cotton knitting fabric DBD pretreatment process is carried out.By comparing with conventional pretreatment process,a suitable plasma technology for cotton knitting fabric pretreatment were obtained by measuring some fabric properties such as weight loss percentage, capillarity effect,degree of whiteness,bursting strength and so on.It is showed in this research that the region of dielectric barrier air plasma treatment is limited to fabric surface,and by a short-time treatment of low concentration of soda and peroxide,the pretreatment effect can be achieved or exceed the conventional one with saving energy and reducing pollution.The optimized plasma pretreatment process:first,the plasma processing with power of 75 watt for 5 min;second,scouring and bleaching:solution composition liquid caustic soda 1.0 g /L and peroxide 5 ml/L→immersing cloth sample→shaking at constant temperature of 85℃for 30min→adding acetic acid at temperature of 65℃for 6min→hot water washing at temperature of 50℃→cold water washing→drying to constant weight.In the plasma pretreatment technology,scouting penetranting agent is not needed so serious pollution can be induced,and the temperature and time for scouring and bleaching is decreased,therefore,energy consumption can be greatly reduced.The results show that better cotton knitting fabric properties were obtained by plasma than that by the conventional pretreatment process,so short-step processing of dry plasma pre-treatment can be achievedThe dying properties of fabrics pretreated by plasma were compared with that by the conventional one.In three concentration of reactive dyes red 3BS(C.I.195),0.5%,1.0%, 1.5%,the dye-up take,color deviation and color fastness to washing and rubbing of the samples are tested respectively.The results show that the dying properties of fabrics pretreated by the plasma technologies maintain or exceed the conventional properties.