Depolymerizable polymers

Depolymerizable polymers or Low-Ceiling Temperature Polymers refer to polymeric materials that can undergo depolymerization to revert the materials to their monomers at relatively low temperatures, such as room temperature. For example, the ceiling temperature Tc for formaldehyde is 119 °C, and that for acetaldehyde is -39 °C.[1]

Introduction

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. The first type of polymers, poly (olefin sulfone), was reported by Snow and Frey in 1943.[2] It was further confirmed and explained in terms of the thermodynamics of a reversible propagation step by Dainton and Ivin.[3]

Applications

The first application of depolymerizable polymers is in transient electronics. Over the past several decades in the electronics industry, the research focus has been on durable and high-strength polymeric materials. Today, however, fast growing consumer electronic products and environmental concerns on electronic wastes, has increased the need for sustainable, recyclable materials. For example, a group of researchers employed light-sensitive poly(phthalaldehyde) as substrate materials for circuits. The destruction of the polymer substrate was triggered by UV irradiation (~379 nm).[1]

gollark: Also also also, the ` ticks_count = 0 # this is supposed to hold the number of ticks we have instanced an object for` on the `Tick` class is not used anywhere.
gollark: Also also, `def __str__(self): pass` doesn't seem to do anything either.
gollark: Also, this function seems to have no valid reason to exist.
gollark: > def indIncreaseCounter(tickInstance):Python convention is to use `snake_case`, not `camelCase`.
gollark: Just looking at this file here: https://github.com/mHappah3019/Tick-Counter/blob/main/TickClass.py> # creates an attribute called identifier and assigns to it> # the value of the "identifier" parameter> # creates an attribute called macro and assigns to it the> # value of the "macro" parameterThese comments are not useful. It is generally assumed that whoever is reading your code is aware of the basics of how the language is used, so your comments should instead describe higher-level stuff like *why* it's doing what it does, what an entire function does, unusual things it might be doing, etc.

References
  1. Kaitz, Joshua A.; Lee, Olivia P.; Moore, Jeffrey S. (2015-01-01). "Depolymerizable polymers: preparation, applications, and future outlook". MRS Communications. 5 (2): 191–204. doi:10.1557/mrc.2015.28. ISSN 2159-6867.
  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. ISSN 0002-7863.
  3. 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. ISSN 1476-4687.


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