Autor según el artículo: Morancho J, Ramis X, Fernández-Francos X, Salla J, Konuray O, Serra

Departamento: Química Analítica i Química Orgànica

Autor/es de la URV: Fernández Francos, Xavier / Serra Albet, Maria Angels

Palabras clave: Toughened epoxy Thermosets Rubber Resins Network structure Mechanism Kinetics Isothermal cure Gelation Epoxy resins Epoxy networks Dual-curing Cure Anhydride

Resumen: 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.

Áreas temáticas: 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

Acceso a la licencia de uso: https://creativecommons.org/licenses/by/3.0/es/

ISSN: 14182874

Direcció de correo del autor: xavier.fernandez@urv.cat angels.serra@urv.cat

Identificador del autor: 0000-0002-3492-2922 0000-0003-1387-0358

Fecha de alta del registro: 2023-07-31

Versión del articulo depositado: info:eu-repo/semantics/acceptedVersion

Enlace a la fuente original: https://link.springer.com/article/10.1007/s10973-019-08681-z

URL Documento de licencia: http://repositori.urv.cat/ca/proteccio-de-dades/

Referencia al articulo segun fuente origial: Journal Of Thermal Analysis And Calorimetry. 138 (4): 2865-2872

Referencia 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 del artículo: 10.1007/s10973-019-08681-z

Entidad: Universitat Rovira i Virgili

Año de publicación de la revista: 2019

Tipo de publicación: Journal Publications