Articles producció científica> Química Analítica i Química Orgànica

Curing and thermomechanical properties of off-stoichiometric anhydride-epoxy thermosets

  • Dades identificatives

    Identificador: imarina:5133043
    Autors:
    Morancho J, Ramis X, Fernández-Francos X, Salla J, Konuray O, Serra
    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.
  • Altres:

    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
    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
    URL Document de llicència: https://repositori.urv.cat/ca/proteccio-de-dades/
    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
  • Paraules clau:

    Chemistry, Analytical,Chemistry, Physical,Condensed Matter Physics,Physical and Theoretical Chemistry,Thermodynamics
    Toughened epoxy
    Thermosets
    Rubber
    Resins
    Network structure
    Mechanism
    Kinetics
    Isothermal cure
    Gelation
    Epoxy resins
    Epoxy networks
    Dual-curing
    Cure
    Anhydride
    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
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