Plastics - Determination of the melt mass-flow rate (MFR) and melt volume flow rate (MVR) of thermoplastics - Part 1: Standard method
|Publication Date:||1 December 2011|
|ICS Code (Thermoplastic materials):||83.080.20|
This part of ISO 1133 specifies two procedures for the
determination of the melt mass-flow rate (MFR) and the melt
volume-flow rate (MVR) of thermoplastic materials under specified
conditions of temperature and load. Procedure A is a
mass-measurement method. Procedure B is a displacement-measure
The MVR is particularly useful when comparing materials of different filler content and when comparing filled with unfilled thermoplastics. The MFR can be determined from MVR measurements, or vice versa, provided the melt density at the test temperature is known.
This part of ISO 1133 is also possibly applicable to thermoplastics for which the rheological behaviour is affected during the measurement by phenomena such as hydrolysis (chain scission), condensation and crosslinking, but only if the effect is limited in extent and only if the repeatability and reproducibility are within an acceptable range. For materials which show significantly affected rheological behaviour during testing, this part of ISO 1133 is not appropriate. In such cases, ISO 1133-2 applies.
NOTE The rates of shear in these methods are much smaller than those used under normal conditions of processing, and therefore it is possible that data obtained by these methods for various thermoplastics will not always correlate with their behaviour during processing. Both methods are used primarily in quality control.