Table 1.
Data for the copolymerizations of lactide and molecule 7.
| Entry | Initial ratioa | Time (h) | solvent | Concb (M) | M/Ic | Calc Mwd (g mol−1) | Polymer ratioe | Convf | Mng (NMR) | Mn (SEC) | Yield | PDI |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 10/1 | 48 | THF | 2.75 | 55 | 9930 | Na | 50% | Na | Na | Na | Na |
| 2 | 10/1 | 48 | CH2Cl2 | 2.75 | 55 | 9930 | 10/1 | 98% | 8670 | 13300 | 85% | 1.55 |
| 3 | 10/1 | 96 | CH2Cl2 | 1.38 | 55 | 9930 | 10/1 | 96% | 7050 | 22700 | 73% | 1.19 |
| 4 | 10/1 | 24 | CH2Cl2 | 2.75 | 55 | 9930 | 10/1 | 85% | 8530 | 7850 | 54% | 1.44 |
| 5 | 10/1 | 48 | CH2Cl2 | 2.50 | 55 | 9930 | 9/1 | 95% | 9200 | 11900 | 81% | 1.25 |
| 6 | 20/1 | 48 | CH2Cl2 | 2.75 | 63 | 10400 | 19/1 | 92% | 9340 | 11000 | 75% | 1.15 |
| 7h | 10/1 | 115 | CH2Cl2 | 2.75 | 110 | 19600 | 11/1 | 95% | 18700 | 88400 | 68% | 1.24 |
| 8h | 20/1 | 115 | CH2Cl2 | 3.15 | 126 | 20500 | 16/1 | 91% | 16200 | 69100 | 82% | 1.21 |
| 9 | 10/1 | 72 | CH2Cl2 | 2.75 | 110 | 19600 | 9/1 | 91% | 14600 | 22700 | 80% | 1.30 |
a
Lactide to molecule 7 ratio in the polymerizations.
b
Concentration of the monomers.
c
Ratio of the sum of the monomers to initiator.
d
Calculated molecular weight based on the ratio of monomers to initiator.
e
Observed ratio of lactide to molecule 7 in the copolymer as shown by 1H NMR spectroscopy.
f
Conversion of the polymerization.
g
The Mn was calculated from by end group analysis using 1H NMR spectroscopy.
h
The temperature of polymerization was 40 °C for these experiments, it was 35 °C for all other polymerizations.