Mechanical Recycling and Reuse of Cured Photopolymer Waste: Size Reduction, Resin Reincorporation and Requalification

Mechanical recycling of a cured photopolymer does not reverse thermoset network formation and does not restore the original liquid resin. The experimentally demonstrated route is different: cured material is mechanically reduced to particles and intentionally reincorporated into a liquid photopolymer, creating a particulate composite and therefore a new formulation state. The recycled fraction can change rheology, recoating, optical transport, cure, interface formation and final properties even when the source waste came from the same nominal resin. ER-183 defines the evidence required to qualify that new state. It separates feedstock identity, size reduction, particle characterisation, dispersion, optical and rheological consequences, printing, post-processing and property verification. It also separates technical reuse from chemical recycling, closed-loop recovery and environmental-superiority claims. No published recycled fraction, particle size or retained-property result is treated as a universal operating limit.