Table 1.
Properties of synthesized poly(butylene succinate), poly(butylene succinate–co–butylene citrate) and poly(butylene citrate).
| Sample | SM:CE:BD | BS:BC (% mol) |
Mn (g/mol) |
Đ | NOH |
Tg (°C) |
Tm (°C) |
ΔH (J/g) |
|---|---|---|---|---|---|---|---|---|
| NG 6 | 1:0:1.07 | 100:0 | 7000 | 2.2 | ≈2 | −18 | 114 | 81 |
| NG 17 | 7:3:10.7 | 68:32 | 7000 | 4.0 | 10 | −33 | 77 | 52 |
| NG 23 | 5:5:10.7 | 52:48 | 8000 | 8.7 | 17 | −29 | 55 | 14 |
| NG 49 | 3:7:10.7 | 27:73 | 7000 | 9.2 | 20 | −29 | - | - |
| NG 48 | 0:1:1.07 | 0:100 | 7500 | 10.5 | 24 | −31 | - | - |
Where: SM:CE:BD—the molar ratio of methyl ester of succinic acid to ethyl ester of citric acid and to used 1,4 butanediol in the starting reaction mixture, BS:BC—the molar ratio of succinate units to citrate units in the copolymer chain, Mn—average molecular weight calculated from 1H NMR spectra, Đ—molecular weight dispersion determined by GPC chromatography, NOH—number of OH groups in the oligomer molecule estimated on the basis of analytical tests carried out in accordance with ASTM D 2849-69, Tg—glass transition temperature, Tm—melting point of the crystalline phase, ΔH—enthalpy of melting the crystalline phase.