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Dear Harry,

I want to know the differences between ASTM  and ISO test procedure for MFR/MFI for PP ? 

Thanks for the question.  There can be diiferences un the test results between the ISO 1133 method and ASTM D1238.  These are mainly due to:

1) there are some slight dimensional differences on the piston foot;

2) the preheat time in ISO is 5 minutes verses 7 +/- 0.5 min in ASTM;

3) the starting point is a 50 mm in ISO and at 46 mm in ASTM

4) the test takes place over a 30 mm piston travel in ISO while the test is limited to 1/4" or 1" of piston travel in the ASTM method.

These are the main differences.  Hope that helps!