What is a high melt flow rate?

What is a high melt flow rate?

What is a high melt flow rate?

Melt flow rate is an indirect measure of molecular weight, with high melt flow rate corresponding to low molecular weight. At the same time, melt flow rate is a measure of the ability of the material’s melt to flow under pressure.

What is melt mass flow rate?

The Melt Mass-Flow Rate is a one number indication of the viscosity of a polymer in the melt phase. It is defined as the mass of polymer in grams flowing per 10 minutes through a capillary of specific diameter and length by a pressure applied via a range of standard weights at specified temperature.

How do you calculate melt flow index?

Melt flow rate values are calculated in g/10 min. melt flow rate = g/10 min.

What is melt volume rate in plastics?

The Melt Flow Rate is a measure of the ease of flow of melted plastic and represents a typical index for Quality Control of thermoplastics. An alternative quantity is the volume flow expressed (SI units) in cm3/10min, called Melt Volume-Flow Rate or MVR.

What material property significantly affects the melt flow rate?

Flow rate in a polymer is related inversely to viscosity. High-viscosity materials flow with greater resistance and therefore more slowly under any particular set of conditions than low-viscosity materials do. Therefore, higher-MW polymers have lower MFR values and lower-MW polymers have higher MFR.

Why is melt flow rate important?

MFI is an important parameter to determine the property of the polymer to flow at melting point under the application of the standard weight (3.2 kg). This MFI is an important parameter, as it provides the necessary data of mass flow rate of the polymer per 10 min.

How do you increase melt flow index?

Mixing with (high MFI) virgin polymers will reduce the risk of mechanical qualities. However in this case you have to add more amounts than in case of lubricant to get high enough MFI, so in general the material cost will increase. You can add very high MFI PP , or else you can add peroxide to boost the melt flow.

What is melt flow index used for?

1 Melt flow index. MFI is a simple measurement of the quantity of polymer pushed through a die of specified dimensions at a set temperature within 10 min. It is frequently used to compare grades of the same polymer, as it gives an indication of the molecular weight present in that batch or grade.