Unlike stable polymers such as PVCs that have high thermal stability, depolymerizable polymers and closely related self-immolative polymers can be triggered by stimuli to break fast under moderate to low temperatures.[3] The first type of polymers, poly (olefinsulfone), was reported by Snow and Frey in 1943.[4] It was further confirmed and explained in terms of the thermodynamics of a reversible propagation step by Dainton and Ivin.[5] Closely related to depolymerizable polymers, self-immolative polymers can also irreversibly disassemble into their constituent parts in response to stimuli such as temperature, biological inputs or pH.[6]
Aspirational applications
Demand for recycling has also prompted search for polymers that are transient. For example, poly(phthalaldehyde) is a possible photodegradable substrate material for circuits..[1] Other applications include controlled release of small molecules, and as stimuli-responsive photoresists for lithography.[7] Some polymers are contemplated for controlled release of drugs.[2]
^Snow, R. D.; Frey, F. E. (1943-12-01). "The Reaction of Sulfur Dioxide with Olefins: the Ceiling Temperature Phenomenon". Journal of the American Chemical Society. 65 (12): 2417–2418. doi:10.1021/ja01252a052. ISSN0002-7863.
^Dainton, F. S.; Ivin, K. J. (1948-10-30). "Reversibility of the Propagation Reaction in Polymerization Processes and its Manifestation in the Phenomenon of a 'Ceiling Temperature'". Nature. 162 (4122): 705–707. doi:10.1038/162705a0. ISSN1476-4687. S2CID4105548.