Author, as appears in the article.: Morancho J; Fernández-Francos X; Acebo C; Ramis X; Salla J; Serra

Department: Química Analítica i Química Orgànica

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

Keywords: Toughening mechanisms Thermosets Thermal curing Rubber Polymers Networks Morphology Matrix resin Kinetics Hyperbranched polymers Epoxy networks Diglycidyl ether Bisphenol-a

Abstract: © 2016, Akadémiai Kiadó, Budapest, Hungary. New hyperbranched polymers (HBP) have been synthesized by reaction of a poly(ethylene imine) with phenyl and t-butyl isocyanates. These HBPs have been characterized by 1H-NMR (nuclear magnetic resonance of hydrogen) and Fourier transform infrared spectroscopy. Their influence on the curing and properties of epoxy-anhydride thermosets has been studied by different techniques: differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and thermogravimetry (TG). The curing kinetics has been studied with DSC. Integral isoconversional method and the Šesták–Berggren model have been used to determine the activation energy and the frequency factor. The kinetic parameters are very similar for all the studied systems at the middle stage of the process, but changes are observed at the beginning and at the end of the process when these modifiers are used. The HBPs reduce the glass transition temperature of the cured materials. In addition, from the DMA analysis it can be seen that the HBP modifier obtained from phenyl isocyanate hardly changes the storage modulus, but the obtained ones from t-butyl isocyanate decrease it. TG analysis reveals a decrease in the onset temperature of the degradation process upon addition of the HBPs.

Thematic Areas: 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

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

ISSN: 14182874

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

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

Record's date: 2023-07-31

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

Link to the original source: https://link.springer.com/article/10.1007/s10973-016-5376-z

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

Papper original source: Journal Of Thermal Analysis And Calorimetry. 127 (1): 645-654

APA: Morancho J; Fernández-Francos X; Acebo C; Ramis X; Salla J; Serra (2017). Thermal curing of an epoxy-anhydride system modified with hyperbranched poly(ethylene imine)s with different terminal groups. Journal Of Thermal Analysis And Calorimetry, 127(1), 645-654. DOI: 10.1007/s10973-016-5376-z

Article's DOI: 10.1007/s10973-016-5376-z

Entity: Universitat Rovira i Virgili

Journal publication year: 2017

Publication Type: Journal Publications