Closed Loop MFI Technology – Whats Happening at Standards.
Today ASTM D1238 for melt flow does not currently accommodate a closed loop MFI it is a weight loading standard only. However, the ASTM Committee D20.30 Thermal Properties, specifically D20.30.08 Thermal Processing Properties responsible for the standard are evaluating closed loop technology, in particular accuracy, repeatability and comparison of the same with dead weight systems. At this point they have a path to updating ASTM D1238 to cover both dead weight and closed loop MFI technology. ISO 1133-1 does allow for closed loop melt flow technology see extract from the standard in pic. That said it does not mean ASTM are lagging, rather they take a different approach proving technology works before they add it to a standard by performing actual comparative material tests to verify measurement performance and capability in key parameters including accuracy, repeatability and being able to define a precision and bias statement. In short ASTM wants