Scope
- Melt Flow Rate assesses the extrusion rate of thermoplastics through an orifice at a specified temperature and load.
- It helps differentiate grades and evaluate the degradation extent of plastics due to molding.
- Degraded materials typically exhibit increased flow due to reduced molecular weight, affecting physical properties.
- Flow rates of resin are determined, and percentage differences are calculated for analysis.
Test Procedure
- Material is loaded into a heated melt flow apparatus.
- A specified weight is applied to the plunger, forcing molten material through a die.
- The extrudate is collected and weighed after a timed interval.
- Melt flow rate values are calculated in grams per 10 minutes.
Specimen Size
- A minimum of 50 grams of material is required for testing.
Data
- Flow rate formula: Flow rate = 600/t x weight of extrudate, where t = time in seconds.
- Melt flow rate is expressed in grams per 10 minutes.
This test description is generic, and standards should be obtained from relevant authorities.