Affiliation:
1. Polymer Competence Center Leoben GmbH Sauraugasse 1 A-8700 Leoben Austria
2. Chair of Chemistry of Polymeric Materials Montanuniversitaet Leoben Otto-Glöckel-Straße 2 A-8700 Leoben Austria
3. Institute of Physical and Theoretical Chemistry Stremayrgasse 9/I (A) A-8010 Graz Austria
Abstract
AbstractChemical amplification is a well‐established concept in photoresist technology, wherein one photochemical event leads to a cascade of follow‐up reactions that facilitate a controlled change in the solubility of a polymer. Herein, we transfer this concept to dynamic polymer networks to liberate both catalyst and functional groups required for bond exchange reactions under UV irradiation. For this, we exploit a photochemically generated acid to catalyse a deprotection reaction of an acid‐labile tert‐butoxycarbonyl group, which is employed to mask the hydroxy groups of a vinyl monomer. At the same time, the released acid serves as a catalyst for thermo‐activated transesterifications between the deprotected hydroxy and ester moieties. Introduced in an orthogonally cured (450 nm) thiol‐click photopolymer, this approach allows for a spatio‐temporally controlled activation of bond exchange reactions, which is crucial in light of the creep resistance versus reflow ability trade‐off of dynamic polymer networks.
Funder
Österreichische Forschungsförderungsgesellschaft
Subject
General Chemistry,Catalysis