Knowledge
ESCR vs Stiffness in Bottle Grades
2026-09-24 · Ascent Group Editorial
Every bottle grade is a compromise between stiffness and environmental stress crack resistance. Raise density and bottles stand square on the shelf but crack sooner around caps filled with surfactants; raise copolymer content and ESCR improves while walls soften.
B5823 sits deliberately in the middle: stiff enough for thin walls and fast cycles, tough enough for household chemicals that destroy brittle grades in months.
The practical test is simple: fill bottles with the harshest product, cap them, and store at elevated temperature. Grades that survive a month there survive the shelf, and that test should precede any price comparison.
