The first photodegradable plastic cap for a glass beer bottle was developed and tested. The cap's design is the same as the current plastic, screw-on cap for soda bottles. A photodegradable resin was added to the soda cap plastic to make it photodegradable. Caps with 0%, 10%, and 25% photodegradable additive were made. Tests show that the photodegradable cap meets most of the physical properties required for a beer or a soda cap. A photodegradable cap with 10% degradable additive will cost about three times more than current metal crowns, but only about 10% more than current plastic soda caps. The photodegradable caps can be made on a large scale using the same process as for regular soda caps. 10,000 caps were made for testing.
© 1990 Society for the Advancement of Material and Process Engineering
Chon, K. S., Idrovo, J. H., Remer, D. S., Pawlek, J. K., and Janati, K. D., "Design and Development of a Photodegradable Bottle Cap," SAMPE Quarterly, 22, 1, 37 (1990).