It is soluble in water, but when its solubility reaches more than 1O, it will form transparent gel in water and lose its fluidity. If a large amount of it is added instantaneously in the dissolution process, a dissolution system with a concentration of more than one thousandth of O will be formed in a certain area of water, which makes the dissolution process difficult to continue. Therefore, it is necessary to add a certain amount of water first, until the blades have not been stirred, and then start the agitator, so that the water solution circulates and then add high purity polyacrylamide. It is required that the stirring blade should not have edges and edges, otherwise it will produce bad effects of hanging materials and shearing high purity polyacrylamide molecular chains, which will make the dissolution concentration inaccurate and weaken its dispersion. The dissolution concentration of high purity polyacrylamide is not too high, generally about 0.5-1 thousandths.