By Felipe Cordero, Polymer Char

Why Is My HDPE Failing In Production When MFI and Density Look Fine?:

When the Polymer Datasheet doesn’t tell the whole story.

Introduction

HDPE bottle handle production is generally considered a highly stable process, particularly when the same resin supplier, grade, and operating conditions are maintained over long production periods. However, unexpected processing failures can still appear after the introduction of a new material lot, even when all incoming quality control parameters, including MFI, density, and average molecular weight, remain within specification. In the present case, a newly received HDPE lot generated recurrent cracking during drop-impact testing of the handles, while the previous lot processed under identical conditions showed no such behavior.