The cause of this accident is considered as the strength decrease by hydrolysis reaction of resin and by
environmental stress cracking. New specimens, whose lamination structure is the same as the failed vessel, were prepared for comparison.
Environmental stress cracking is a failure mechanism whereby a plastic material cracks due to contact with an incompatible chemical agent while under tensile stress.
In order to investigate the susceptibility of different materials or a number of chemical environments to
environmental stress cracking or premature ruptures, it is possible to use monotonic creep tests (ref.
The
environmental stress cracking resistance (ESCR) values of the bottles for differing preform reheat set temperatures are given in Table 5.
They are made using the company's Lupotech G low pressure gas phase process and are noted for their cold temperature impact and
environmental stress cracking resistance.
The products resist soil stress, under-film moisture migration,
environmental stress cracking, and mechanical damage from handling.
Fabrications are manufactured from 3/16 to 1 1/2" homogeneous polypropylene, a rugged, resilient material that is UV-stable and not subject to delamination or
environmental stress cracking, per ASTM D-1693, also FM 4910 clean-room standards.
Environmental stress cracking (ESC) is considered a leading cause of plastic part failure.
Plastics haven't successfully weathered the germ eradication campaign in every instance, succumbing to
environmental stress cracking and even mechanical failures, forcing unwanted recalls.
It has been estimated that 15% of all failures of plastic materials in commercial use are related to
environmental stress cracking (ESC) (3).
This brings returns in faster processing, and also reduces internal stress that could cause
environmental stress cracking of the finished caps.
Polyether polyurethanes, while hydrolytically stable, are subject to oxidative degradation in several forms, including
environmental stress cracking and metal ion oxidation.