How does an MFI tester help in determining the viscosity of molten plastics?

Description : An MFI (Melt Flow Index) tester determines the viscosity of molten plastics by measuring the rate at which a standardized amount of plastic extrudes through a specified orifice under standard conditions of temperature and pressure. The plastic sample is loaded into a heated barrel and subjected to a constant load, causing it to melt. The molten plastic then flows through the orifice, and the time taken for a specific volume of plastic to extrude is recorded. This measurement provides a quantitative indication of the flow properties or viscosity of the molten plastic. In essence, the MFI tester quantifies how easily the plastic flows under standardized conditions, allowing for the assessment of its processability and quality in various plastic manufacturing applications.