Table 2.
Polymerization data for rac‐LA with catalysts 1–5.[a]
| init. | k p (L mol−1 s−1)[b] | k app (s−1) [c] | time (min) | conv. (%)[d] | M n,theo (g mol−1)[e] | M n (g mol−1)[f] | PD |
|---|---|---|---|---|---|---|---|
| 1 | 1.22±0.15×10−3 | 41 | 79 | 57 000 | 62 000 | 1.6 | |
| 2 | 8.59±0.36×10−2 | 1.14±0.04×10−3 | 25 | 62 | 45 000 | 65 000 | 1.5 |
| 4 | 1.41±0.01×10−3 | 42 | 78 | 56 000 | 71 000 | 1.5 | |
| 5 | 6.08± 0.1×10−4 | 49 | 75 | 54 000 | 57 000 | 1.6 |
[a] Conditions: solvent free, non‐purified technical grade rac‐LA, 150 °C. [b] Determined by plotting k app versus [init.]. k p [I] [M]; k p=k app/[I]. [c] Determined from the slope of the plots of ln([LA]0/[LA]t) versus time for a ratio of [M]/[I]=500 : 1. [d] As determined by 1H NMR spectroscopy. [e] Calculated assuming that every zinc of each dinuclear complex propagates one chain M n,theo: 72 000 g mol−1 for 100 % conversion at a ratio of [M]/[I]=500 : 1. [f] Determined by GPC (in THF).