Work

Disulfide‐Induced Inhibition of Epoxy Cationic Photopolymerization: A Route to Maskless Patterning

Year: 2026

Type: article

Abstract: In photoinduced cationic ring-opening polymerization (ROP) of epoxy monomers, chain-transfer reactions in the presence of alcohols are well established, and monosulfides are known to inhibit polymerization even at very low loadings (i.e., 0.01 mol%). Herein, it is thoroughly investigated the role of a disulfide-containing diol in quenching the polymerization of a difunctional epoxy formulation. Differently from the monosulfide, the propagation can start, and only at high sulfur:epoxy ratio the reactions of the disulfides with the oxonium ions effectively compete with the propagation and stops the polymerization. This inhibition mechanism can be exploited as a novel maskless photolithographic approach, enabling the spatially controlled patterning of epoxy coatings through localized deposition of the disulfide diol. As a proof of concept, sharply defined features with sizes down to 200 µm are successfully fabricated. These results introduce disulfide-mediated polymerization quenching as a versatile and material-efficient method for epoxy photopatterning.

Source: Macromolecular Rapid Communications

DOI: 10.1002/marc.202500956

Authors: Alberto Spessa, Roberta Bongiovanni, Alessandra Vitale

Institutions: Politecnico di Torino, National Interuniversity Consortium of Materials Science and Technology

Language: English

Topic: Photopolymerization techniques and applications

Subfield: Organic Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,550

Funder: Politecnico di Torino