For the characterization and comparison of polyethylene grades used for the manufacture of
packagings and Intermediate Bulk Container (IBC) the following parameters are required: melt
flow rate (MFR), density (D), low temperature notched impact strength (NIS), Full Notch Creep
Test (FNCT) and increase of MFR by molecular degradation (Ox). The correlation of these material
parameters determined on the basis of specimens prepared from compression moulded
sheets of polyethylene grades and the test behavior of packagings has been investigated in
several tests.
The environmental stress crack resistance determined by Full Notch Creep Test (FNCT)
represents the impacts from the stacking tests at 40 °C performed with standard liquid wetting
solution (without pre-storage) and with normal butyl acetate saturated wetting solution (prestorage
with normal butyl acetate). The molecular degradation by the determination of MFR
increase represents the impacts from the drop test and stacking tests performed after prestorage
(21 and 42 days at 40 °C) with standard liquid 55 % nitric acid.
The low temperature impact strength represents the impacts from the drop test at -18 °C performed
without pre-storage and after pre-storage with standard liquid 55 % nitric acid.
A good correlation was found between the test results and the material parameters.
Keywords: dangerous goods packagings, HDPE grades, material parameters, design type
tests