Characters: White or off-white amorphous powder, odourless, tasteless, soluble in hot water, insoluble in ethanol. Its water solution is colorless transparent liquid or clear liquid with slight milky light. Uses: 1. Medicine for blood volume expansion, increase plasma colloid osmotic pressure, increase of plasma volume and maintain blood pressure, can prevent the red blood cell and platelet aggregation, reduce blood viscosity, which has the effect of improving microcirculation. The goods mainly through the kidneys in vitro, the discharge rate and the size of the molecular weight. When the body after 1 hour, low, small molecule Dextran respectively from the eduction in urine was 30%, 50%, 70%; After 24 hours, respectively, from 60%, 70%, 80% 2. widely used in chemical industry as an important raw material, play an important role as sewage treatment agent, etc.