resumo
In this study, poly-(glycerol-co-diacids)prepolymerswere produced using different ratios of glycerol (G), sebacic acid(S), and succinic acid (Su) (molar ratios: GS 1:1, GSSu 1:0.9:0.1,GSSu 1:0.8:0.2, GSSu 1:0.5:0.5, GSSu 1:0.2:0.8, GSSu 1:0.1:0.9, GSu1:1). All polycondensation reactions were performed at 150 degrees Cuntil reaching a degree of polymerization of approximate to 55%, inferredby the water volume collected from a reactor. We concluded that thereaction time is correlated with the ratio of diacids used, that is,the increase in succinic acid is proportional to a decrease in theduration of the reaction. In fact, the reaction of poly-(glycerol sebacate)(PGS 1:1) is twice as slow as the reaction of poly-(glycerol succinate)(PGSu 1:1). The obtained prepolymers were analyzed by electrosprayionization mass spectrometry (ESI-MS) and H-1 and C-13 nuclear magnetic resonance (NMR). Besides its catalytic influencein poly-(glycerol)/ether bond formation, the presence of succinic acidalso contributes to a mass growth of ester oligomers, the formationof cyclic structures, a greater number of oligomers detected, anda difference in mass distribution. When compared with PGS (1:1), andeven at lower ratios, the prepolymers produced with succinic acidpresented mass peak characteristics of oligomer species with a glycerolunit as its end group in higher abundance. Generally, the most abundantoligomers have molecular weights between 400 and 800 g/mol.
palavras-chave
ENZYMATIC DEGRADATION; SEBACATE) SYNTHESIS; GLYCEROL; NETWORK; SUCCINATE-CO-MALEATE); OPTIMIZATION; ELASTOMER; TOUGHNESS; POLYMER; PGS
categoria
Chemistry
autores
Godinho, B; Nogueira, R; Gama, N; Ferreira, A
nossos autores
Artur Jorge Faria Ferreira
Professor Coordenador
Bruno Miguel Marques Godinho
Estudante de doutoramento
Nuno Vasco da Costa Gama Batista de Melo
Investigador JúniorProjectos
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
agradecimentos
This work was financed by Portugal 2020 through European Regional Development Fund (ERDF) in the frame of Operational Competitiveness and Internationalization Programme (POCI) in the scope of the project ECOFOAM, POCI/CENTRO-01-0247-FEDER-49287 and in the scope of the project CICECO?Aveiro Institute of Materials, UIDB/50011/2020 & UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MEC (PIDDAC). The authors also thank the Mass Spectrometry Center of the University of Aveiro and the Portuguese Nuclear Magnetic Resonance Network (PTNMR), of which the University of Aveiro is a member, for the analyses performed.