TY - JOUR

T1 - Dual-Wavelength Vat Photopolymerization 3D Printing with Hybrid Acrylate-Epoxy Resins

T2 - Influence of Resin Composition on Microstructure and Mechanical Properties

AU - Cazin, Ines

AU - Plevová, Kateřina

AU - Alabiso, Walter

AU - Vidović, Elvira

AU - Schlögl, Sandra

N1 - Publisher Copyright: © 2024 Wiley-VCH GmbH.

PY - 2024/4

Y1 - 2024/4

N2 - Dual-wavelength vat photopolymerization 3D printing represents a convenient technology for the fabrication of objects with heterogeneous and locally controlled mechanical properties. By using two λ-orthogonal cross-linking reactions, it is possible to produce soft and stiff photopolymers with a single resin vat by switching the light source. Herein, hybrid acrylate-epoxy resins are selectively cured by using either visible or UV light. At 405 nm, a free radical curing of the acrylate monomers is induced while irradiation with 365 nm triggers an additional cationic ring opening reaction of the epoxy monomer yielding interpenetrating photopolymer networks. In a comprehensive approach, the influence of the resin composition and the applied wavelength on cure kinetics, film morphology, (thermo)mechanical properties, and printability are studied. Fully separated as well as homogenous network morphologies are obtained depending on the ratio between acrylate and epoxy monomers, cure rate and applied light source (405 vs 365 nm). In general, glass transition temperature, stiffness, and tensile strength of the photopolymers increase with rising epoxy content. In contrast, a higher epoxy concentration in combination with a higher amount of the cationic photoinitiator compromises on the system's orthogonality, giving rise to the important role of the resin composition in dual-wavelength vat photopolymerization 3D printing.

AB - Dual-wavelength vat photopolymerization 3D printing represents a convenient technology for the fabrication of objects with heterogeneous and locally controlled mechanical properties. By using two λ-orthogonal cross-linking reactions, it is possible to produce soft and stiff photopolymers with a single resin vat by switching the light source. Herein, hybrid acrylate-epoxy resins are selectively cured by using either visible or UV light. At 405 nm, a free radical curing of the acrylate monomers is induced while irradiation with 365 nm triggers an additional cationic ring opening reaction of the epoxy monomer yielding interpenetrating photopolymer networks. In a comprehensive approach, the influence of the resin composition and the applied wavelength on cure kinetics, film morphology, (thermo)mechanical properties, and printability are studied. Fully separated as well as homogenous network morphologies are obtained depending on the ratio between acrylate and epoxy monomers, cure rate and applied light source (405 vs 365 nm). In general, glass transition temperature, stiffness, and tensile strength of the photopolymers increase with rising epoxy content. In contrast, a higher epoxy concentration in combination with a higher amount of the cationic photoinitiator compromises on the system's orthogonality, giving rise to the important role of the resin composition in dual-wavelength vat photopolymerization 3D printing.

KW - dual-wavelength vat photopolymerization 3D printings

KW - heterogeneous properties

KW - hybrid radical/cationic photopolymers

KW - multi-materials

KW - polymer morphologies

UR - http://www.scopus.com/inward/record.url?scp=85187500695&partnerID=8YFLogxK

U2 - 10.1002/adem.202301699

DO - 10.1002/adem.202301699

M3 - Article

AN - SCOPUS:85187500695

VL - 26.2024

JO - Advanced Engineering Materials

JF - Advanced Engineering Materials

SN - 1438-1656

IS - 8

M1 - 2301699

ER -