Dual-Cure Coatings: Spiroorthoesters as Volume-Controlling Additives in Thiol–Ene Reactions
Publikationen: Beitrag in Fachzeitschrift › Artikel › Forschung › (peer-reviewed)
Standard
in: Macromolecular materials and engineering, Jahrgang 304.2019, Nr. 4, 1800627, 04.2019.
Publikationen: Beitrag in Fachzeitschrift › Artikel › Forschung › (peer-reviewed)
Harvard
APA
Vancouver
Author
Bibtex - Download
}
RIS (suitable for import to EndNote) - Download
TY - JOUR
T1 - Dual-Cure Coatings
T2 - Spiroorthoesters as Volume-Controlling Additives in Thiol–Ene Reactions
AU - Marx, Philipp
AU - Romano, Angelo
AU - Fischer, Roland
AU - Roppolo, Ignazio
AU - Sangermano, Marco
AU - Wiesbrock, Frank
N1 - Publisher Copyright: © 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
PY - 2019/4
Y1 - 2019/4
N2 - Most thiol–ene systems exhibit shrinkage during cross-linking, potentially resulting in micro-cracks and delamination. Oligocyclic monomers like spiroorthoesters (SOEs), on the contrary, show expansion during the ring-opening polymerization. In this communication, a photocurable thiol–ene system composed of a trifunctional thiol, a bisfunctional allyl-bisphenol A compound, and an SOE compound bearing one olefin function shows expansion in the range from −3.07 to +1.70 vol% if the SOE content is increased from 0–30 wt%. Network formation can be accomplished under visible light if a radical as well as a cationic photoinitiator (dual-cure mechanism) and a sensitizer are used. The elasticity of the cured resin increases upon the addition of the SOE; correspondingly, the glass-transition temperature shows a (minor) decrease from 16 to 3 °C. A tailor-made combination of the allyl-bisphenol A compound (90 wt%) and the SOE (10 wt%) yields networks that are volume-neutral during curing.
AB - Most thiol–ene systems exhibit shrinkage during cross-linking, potentially resulting in micro-cracks and delamination. Oligocyclic monomers like spiroorthoesters (SOEs), on the contrary, show expansion during the ring-opening polymerization. In this communication, a photocurable thiol–ene system composed of a trifunctional thiol, a bisfunctional allyl-bisphenol A compound, and an SOE compound bearing one olefin function shows expansion in the range from −3.07 to +1.70 vol% if the SOE content is increased from 0–30 wt%. Network formation can be accomplished under visible light if a radical as well as a cationic photoinitiator (dual-cure mechanism) and a sensitizer are used. The elasticity of the cured resin increases upon the addition of the SOE; correspondingly, the glass-transition temperature shows a (minor) decrease from 16 to 3 °C. A tailor-made combination of the allyl-bisphenol A compound (90 wt%) and the SOE (10 wt%) yields networks that are volume-neutral during curing.
KW - dual-cure mechanisms
KW - spiroorthoesters
KW - thiol–ene reactions
KW - thiol–ene resins
KW - UV-mediated curing
KW - volumetric expansion
UR - http://www.scopus.com/inward/record.url?scp=85060189625&partnerID=8YFLogxK
U2 - 10.1002/mame.201800627
DO - 10.1002/mame.201800627
M3 - Article
AN - SCOPUS:85060189625
VL - 304.2019
JO - Macromolecular materials and engineering
JF - Macromolecular materials and engineering
SN - 1438-7492
IS - 4
M1 - 1800627
ER -