Effect of Piston Travel and Starting Position on Measurement Results of Polyethylene Melt Flow Rate

In order to determine the effect of piston travel and piston starting position on the measurement results of polyethylene melt flow rate, different polyethylene resin samples with varying melt flow rates were tested in experiment with procedure B (automatically timed flow rate measurement). The results showed that, under the same piston travel, the closer the starting position by different instrument, the similar the measurement results; by the same instrument, the effect of piston travel on measurement result increased with the increase of melt flow rate. The research results provided the basis for the unity of piston travel distance and starting position in the melt flow rate measurement.