Thermal behaviour and fungi resistance of composites based on wood and natural and synthetic epoxy resins cured with maleopimaric acid

• Published in: Polymer degradation and stability Vol. 160; pp. 148 - 161
• Main Authors: Rosu, Liliana, Mustata, Fanica, Varganici, Cristian–Dragos, Rosu, Dan, Rusu, Teodora, Rosca, Irina
• Format: Journal Article
• Language: English
• Published: London Elsevier Ltd 01.02.2019; Elsevier BV
• Subjects: Acetic acid; Acetone; Adducts; Anhydrides; Biological resistance; Biopolymers; Bisphenol A; Composite materials; Crosslinking; Cure behaviour; Cyclohexane; Differential scanning calorimetry; Epoxidation; Epoxy resins; Fungi; Heat conductivity; Hydrogen peroxide; Maleic anhydride; Maleopimaric acid; Organic chemistry; Polymer matrix composites; Sulfuric acid; Synthetic products; Thermal decomposition; Thermal degradation; Thermal properties; Thermal resistance; Thermodynamic properties; Thermogravimetric analysis; Thermosetting resin; Wood; Thermal properties; Biological resistance; Cure behaviour; Wood; Thermosetting resin
• ISSN: 0141-3910; 1873-2321
• DOI: 10.1016/j.polymdegradstab.2018.12.022

Wood/epoxy resin composites based on diglycidyl ether of bisphenol A (DGEBA)/epoxidized oil (EO)/Diels–Alder adducts of resin acids with maleic anhydride (RAMA) in acetone (80%) were obtained by impregnation. Epoxidation was carried out in the presence of hydrogen peroxide (H2O2), acetic acid (AAc), sulfuric acid (H2SO4) as catalyst and cyclohexane (CHx) as solvent at a molar ratio of 0.5/1.5/1 (AAc/hydrogen peroxide/ethylene unsaturation). The kinetic parameters (activation energy and pre–exponential factor) of the DGEBA/EO/RAMA curing reaction and thermal characterization of the crosslinked compounds and wood epoxy composites (WECs) were obtained using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Based on the chemical structure of the evolved gases resulted during thermal decomposition of the crosslinked polymers and WECs, identified with FT–IR, a probable mechanism of thermal degradation was proposed. Resistance to three fungi was also tested. •New synthetic and natural epoxy derivatives as wood coatings were obtained.•The epoxy derivatives were thermally crosslinked.•The influence of coating on wood thermal stability and fungi resistance was made.