Autor segons l'article: Morancho J, Ramis X, Fernández-Francos X, Salla J, Konuray O, Serra
Departament: Química Analítica i Química Orgànica
Autor/s de la URV: Fernández Francos, Xavier / Serra Albet, Maria Angels
Paraules clau: Toughened epoxy Thermosets Rubber Resins Network structure Mechanism Kinetics Isothermal cure Gelation Epoxy resins Epoxy networks Dual-curing Cure Anhydride
Resum: In the present work, we report the preparation and characterization of a new family of thermosets based on off-stoichiometric anhydride-epoxy formulations in the presence of an anionic initiator. Diglycidyl ether of bisphenol A (DGEBA) and hexahydro-4-methylphthalic anhydride (HHMPA) have been used as epoxy and anhydride comonomers, respectively, and 1-methylimidazole (1MI) has been used as anionic initiator. The isothermal curing kinetics and the thermal properties of the stoichiometric and the off-stoichiometric systems have been compared. The kinetics of the isothermal curing has been analyzed by differential scanning calorimetry (DSC) using an isoconversional method and the Sestak-Berggren equation to determine the activation energy, the frequency factor and the reaction orders. The materials obtained were characterized by DSC and dynamic mechanical analysis. Gelation during epoxy-anhydride condensation was determined by thermomechanical analysis. At the same curing temperature, the reaction is faster in the system with excess of epoxy groups. However, the glass transition temperatures of the partially cured stoichiometric system are greater. The gelation time of the off-stoichiometric system is shorter than that of the stoichiometric one. The results indicate that the dual-curing character of off-stoichiometric DGEBA/HHMPA thermosets with 1MI as anionic initiator makes them suitable for multistage curing processes with easy control of degree of cure and material properties in the intermediate stage and enhanced final material properties.
Àrees temàtiques: Zootecnia / recursos pesqueiros Thermodynamics Saúde coletiva Química Polymers and plastics Physical and theoretical chemistry Odontología Nutrição Medicina ii Medicina i Materials chemistry Materiais Interdisciplinar Geociências Farmacia Ensino Engenharias iv Engenharias iii Engenharias ii Engenharias i Educação Economia Dentistry (all) Condensed matter physics Ciências biológicas iii Ciências biológicas ii Ciências biológicas i Ciências ambientais Ciências agrárias i Ciência de alimentos Chemistry, physical Chemistry, analytical Biotecnología Biodiversidade Astronomia / física Arquitetura e urbanismo
Accès a la llicència d'ús: https://creativecommons.org/licenses/by/3.0/es/
ISSN: 14182874
Adreça de correu electrònic de l'autor: xavier.fernandez@urv.cat angels.serra@urv.cat
Identificador de l'autor: 0000-0002-3492-2922 0000-0003-1387-0358
Data d'alta del registre: 2023-07-31
Versió de l'article dipositat: info:eu-repo/semantics/acceptedVersion
Enllaç font original: https://link.springer.com/article/10.1007/s10973-019-08681-z
URL Document de llicència: http://repositori.urv.cat/ca/proteccio-de-dades/
Referència a l'article segons font original: Journal Of Thermal Analysis And Calorimetry. 138 (4): 2865-2872
Referència de l'ítem segons les normes APA: Morancho J, Ramis X, Fernández-Francos X, Salla J, Konuray O, Serra (2019). Curing and thermomechanical properties of off-stoichiometric anhydride-epoxy thermosets. Journal Of Thermal Analysis And Calorimetry, 138(4), 2865-2872. DOI: 10.1007/s10973-019-08681-z
DOI de l'article: 10.1007/s10973-019-08681-z
Entitat: Universitat Rovira i Virgili
Any de publicació de la revista: 2019
Tipus de publicació: Journal Publications
Repositori URV