Purification and Reuse of Products from Triggered Photopolymer Depolymerisation: Composition, Functionality and Closed-Loop Evidence

Triggered depolymerisation can convert a printed network into soluble products, but network disappearance does not by itself establish a reusable feedstock. Published systems span thioester networks degraded to functional oligomers that can be repolymerised [1], deliberately recyclable photoresins that return functional material to later printing [2], and lipoate-based vat-photopolymer resins that were depolymerised, chemically characterised and reprinted across repeated cycles [3]. These routes differ in whether the recovered material is an oligomer, a monomer-like cyclic species or a compositionally mixed resin; in the fresh reactants required for the next cycle; and in the purification burden. ER-275 therefore owns the post-depolymerisation decision chain: identify all products, separate reusable from non-reusable fractions, quantify functionality and impurities, account for fresh inputs, demonstrate formulation and printing fitness, and report cycle-resolved retention. It does not prescribe a trigger chemistry or purification recipe and does not treat high isolated yield or successful reprinting as proof of chemical identity, closed-loop mass balance or environmental benefit.

ER-275 · Version v0.2.