Influence Factors of Measuring Results of Viscosity of Polypropylene Solution

The reduced viscosity of polypropylene solution was measured by automatic capillary viscometer. The influence of mass concentration, mixing time, rotating speed and exposed time in the air on the measuring results of reduced viscosity of polypropylene solution was investigated. The results show that:the mass concentration of polypropylene solution affected its reduced viscosity greatly, and the solution whose mass concentration was between 0.001-0.005 g·mL^-1 was suitable to measure the reduced viscosity; when the mixing time was 2 h and the rotating speed was 1200 r·h^-1, the polypropylene solution dissolved into homogeneous system completely; the reduce viscosity had small change after the polypropylene solution exposed in the air for a short time, and the phase separation happened to the solution after the polypropylene solution exposed in the air for a long time, and then the reduced viscosity decreased.