Table 1.
Ring opening polymerization of TBODC and ε- caprolactone (CL) catalyzed by SnOct2 a.
| Entry | f TBODC/ε-CL b | 1H NMR | GPC e | DSC | |||
|---|---|---|---|---|---|---|---|
| F c | Mn/kDa d | Mn/kDa | Đ | Tg/°C | Tm/°C | ||
| 1 | 10/90 | 7.1 | 8.3 | 8.7 | 1.26 | −47.15 | 49.54 |
| 2 | 25/75 | 22.8 | 10.7 | 14.9 | 1.58 | −40.73 | 36.53 |
| 3 | 50/50 | 50.9 | 3.9 | 17.7 | 1.30 | −34.59 | N/A |
| 4 | 100/0 | N/A | 4.8 | 3.3 | 1.10 | 48.45 | N/A |
| 5 | 0/100 | N/A | 12.2 | 8.3 | 1.40 | /f | 63.50 |
a Polymerization conditions: [comonomer]/[BnOH]/[SnOct2] = 100/1/0.5, 100 °C, 24 h, 1 M in toluene; b feed ratio of TBODC to ε-CL in comonomer; c TBODC segment ratio in copolymers which is determined by 1H NMR via 0.5 × I4.14ppm/(0.5 × I4.14ppm + 0.5 × I2.31ppm); d molecular weight calculated by 1H NMR via 0.5 × I4.14 ppm × 217.22 + 0.5 × I2.31 ppm × 114.14 + 107.41; e THF used as elution; f Tg of PCL was not detected due to cooling depth limitation.