What are the environmental stress cracking resistance (ESCR) tests for polyethylene?
Environmental Stress Cracking Resistance (ESCR) is a critical property for polyethylene, especially in applications exposed to harsh conditions. Several standardized tests evaluate ESCR, with ASTM D1693 being the most widely recognized. This test involves immersing notched polyethylene samples in a surfactant solution under constant strain, then measuring the time until cracks appear. Other methods include ISO 4599 and ASTM D5397, which assess resistance under bending or tensile stress. High-density polyethylene (HDPE) often undergoes these tests due to its susceptibility to stress cracking. Results help manufacturers ensure material durability for pipes, containers, and outdoor products. Understanding ESCR tests is essential for selecting the right polyethylene grade for long-term performance.
