resumo
In recent years, thermoset elastomers, particularly polyesters derived from the polycondensation of glycerol and non-toxic diacids, have garnered significant interest. This study focuses on the synthesis of poly(glycerol-co-diacids) polymers using varying molar ratios of glycerol (G), sebacic acid (S), and succinic acid (Su). Seven distinct ratios were investigated (PGS (1:1), PGSSu (1:0.9:0.1), PGSSu (1:0.8:0.2), PGSSu (1:0.5:0.5), PGSSu (1:0.2:0.8), PGSSu (1:0.1:0.9) and PGSu (1:1)). The resulting polymers were analyzed using Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), dynamic mechanical analyses (DMA), tensile tests, scanning electron microscopy (SEM), gel fraction and degree of swelling determination. Among the synthesized polymers, PGS (1:1) and PGSu (1:1) exhibited superior mechanical robustness than the polymers obtained by mixing diacids. The results show that the incorporation of succinic acid in the synthesis of the polymers progressively led to rougher surfaces and a reduction in thermal resistance compared to PGS (1:1). PGSu (1:1) showed the highest surface roughness and the lowest thermal resistance. The glass transition temperature (T g ) for these elastomers ranged from - 30 degrees C to 30 degrees C. Additionally, higher ratios of succinic acid led to increased polymer density and less degree of swelling. The gel fraction of these polymers ranged from 70 to 95%. PGS (1:1) with the lowest and PGSu (1:1) with the highest gel fraction, respectively.
palavras-chave
ENZYMATIC DEGRADATION; GLYCEROL; ACID; ELASTOMERS; POLYESTER; NETWORK; SUCCINATE-CO-MALEATE); CYTOTOXICITY; TOUGHNESS; FIBERS
categoria
Engineering; Polymer Science
autores
Godinho, B; Nogueira, R; Gama, N; Ferreira, A
nossos autores
Artur Jorge Faria Ferreira
Professor Coordenador
Bruno Miguel Marques Godinho
Investigador
Nuno Vasco da Costa Gama Batista de Melo
Investigador Júnioragradecimentos
We thank LAT (Laboratory for Thermal Analysis) and Ana Caco, analysis technician, from the Chemical Department of the University of Aveiro for the TGA and DMA analysis.