Author, as appears in the article.: Konuray O; Di Donato F; Sangermano M; Bonada J; Tercjak A; Fernández-Francos X; Serra ; Ramis X

Department: Química Analítica i Química Orgànica

URV's Author/s: Fernández Francos, Xavier / Serra Albet, Maria Angels

Keywords: Thermosetting resins Stereolithography Projection Polyester Optimization Ether Epoxy thermosets Epoxy Dual-curing Cationic-polymerization Accuracy

Abstract: © 2020, BME-PT and GTE. All rights reserved. Stereolithography (SL) stands out as a relatively fast additive manufacturing method to produce thermoset components with high resolutions. The majority of SL resins consist of acrylate monomers which result in materials with cur-ing-induced shrinkage problems and this, in addition to the incomplete and non-uniform conversions reached in the SL process, results in poor mechanical properties. To address this issue, a dual-curing formulation was developed by mixing an epoxy monomer into a commercial multi-acrylate SL resin: the first curing stage is acrylate free-radical photopolymerization at ambient temperature, and the second curing stage is cationic epoxy homopolymerization at higher temperatures. The fully dual-cured materials are macroscopically homogeneous, with nanoscale domains observed by Atomic Force Mi-croscopy (AFM), and with unimodal tan delta peaks observed in Dynamic Mechanical Analysis (DMA). The uncured material was storage stable at ambient conditions for at least 9 weeks since the epoxy part was virtually unreactive at these temper-atures. With the dual-cured materials, a nearly 10-fold increase in Young’s modulus was achieved over the neat acrylate resin. At the thermal curing stage, the presence of diperoxyketal thermal radical initiator to the liquid formulation facilitated the polymerization of unreacted acrylates that remained from the SL process simultaneously with epoxy homopolymerization and helped the material attain improved properties.

Thematic Areas: Química Polymers and plastics Polymer science Physical and theoretical chemistry Organic chemistry Odontología Materials chemistry Materiais Interdisciplinar General chemical engineering Farmacia Engenharias iv Engenharias iii Engenharias ii Ciências biológicas iii Ciências biológicas i Ciências ambientais Chemical engineering (miscellaneous) Chemical engineering (all) Biotecnología Astronomia / física

licence for use: https://creativecommons.org/licenses/by/3.0/es/

ISSN: 1788-618X

Author's mail: xavier.fernandez@urv.cat angels.serra@urv.cat

Author identifier: 0000-0002-3492-2922 0000-0003-1387-0358

Last page: 894

Record's date: 2023-02-19

Journal volume: 14

Papper version: info:eu-repo/semantics/publishedVersion

Link to the original source: https://upcommons.upc.edu/handle/2117/329558

Licence document URL: http://repositori.urv.cat/ca/proteccio-de-dades/

Papper original source: Express Polymer Letters. 14 (9): 881-894

APA: Konuray O; Di Donato F; Sangermano M; Bonada J; Tercjak A; Fernández-Francos X; Serra ; Ramis X (2020). Dual-curable stereolithography resins for superior thermomechanical properties. Express Polymer Letters, 14(9), 881-894. DOI: 10.3144/expresspolymlett.2020.72

Article's DOI: 10.3144/expresspolymlett.2020.72

Entity: Universitat Rovira i Virgili

Journal publication year: 2020

First page: 881

Publication Type: Journal Publications