Prepared By Nmmo Method Spun Hollow Fiber Membrane Artificial Kidney

Cellulose and its derivation membranes are promident in the development history of hemodialysis membranes because they have a good characteristic and their crude materials are easy to obtain and they have a lower price than others. Not only many countries think much of the study of this kind of membrane, but also does this kind of membrane affect the research of novel hemodialysis membranes . A traditional preparing mothed of this kind of membrane is cuprammonium. This mothed has a complicated procedure which are less and less satified with the requirement of environment protecting. Although the membrane from this mothed has a good permeability to urea,creatinine and some low molecular weight, the permeability to middle and high molecular weight is not enough.In this paper, A novel solvent N-methylmorpholine-N oxide was used to solve cellulose.The solving condition and rheological behavior were investigated. Then, Cellulose/carboxyl chitosan hollow fiber membrane was spinned. Several spinning procedure conditions were discussed, such as coagulation bath concentration, temperature, extruding rate and core layer liquid flow rate etc. some influences of cellulose pulp, making aperture reagent and blend reagent of membrane characteristics were studied. And the dialysis characteristics and blood anticoagulant activity of membrane were tested.Some conclusions can be drew from the experiment. The optimal swelling and solving time and temperature were about 6 hours, 2 hours and 90 C, 105 C,respectively; and hollow fiber can be succeedly spinned when cellulose pulp concentration was in 8%; fiber figuration rate increased with the coagulation bath temperature increasing; and the membrane flux increased with the coagulation both temperature increasing. In addition, the membrane structure was thick when coagulation bath temperature was below 10 C, and the structure became porous when coagulation bath temperature increased to 20 C.The maximum spinning speed decreased with the coagulation bath concentration increasing. And hollow fibers' out layer diameter, membrane wall thickness and porosity increased and the flux decreased when extruding volumn flux increased. Alsothe optimal DP was about 600, and the DP of cellulose pulp can't decide all characteristics of membrane . However, the property of membrane was obviously effected by the constitudes.Dialysis characteristics of membrane were tested, and several conclusions were drawn. The ultrafiltration rate of pure water of hollow fiber membrane decreased but the sieving coefficient of dextran increased with the cellulose concentration increasing; Adding PVP to solution have a little influence on the dialysis characteristics of hollow fiber membrane, at the same time, the ultrafiltration rate of pure water increasly decreased and sieving coefficient of dextran increased also. The ultrafiltration rate of pure water with the coagulation bath temperature increased.The anticoagulant activity of membrane were tested. It was found that the experiment of hemolysis showed that the hemolysis ratio of the blend membrane accorded with the country standard.After studing this experiment, we got to know that solving and spinning procedure were simple which avoided the serious pollution;Introducing carboxyl chitosan can partly enchance the blood anticoagulant activity. This kind of artificial kidney dialyzer, which emphysis on environment protecting and have a good blood flexibility, is suggested to a fine foreground.