Table 1. Ethylene Polymerization of C1 with Different Cocatalystsa.
| entry | cocatalyst | time (min) | yield (g) | productivity (kg mol–1Ni h) | TOF (103)(h–1) | B/1000Cb | Mnc (kg mol–1) | Đc | Tmd (°C) |
|---|---|---|---|---|---|---|---|---|---|
| 1e | MMAO (200 equiv) | 5 | 3.0 | 18,000 | 642.9 | 27 | 6.5 | 2.47 | 109.3 |
| 2e | Et2AlCl (200 equiv) | 5 | 2.5 | 15,000 | 535.7 | 40 | 4.0 | 2.11 | 102.7 |
| 3 | NaBArF (1.2 equiv) | 10 | 0.3 | 360 | 12.9 | 26 | 8.5 | 1.98 | 108.3 |
| 4 | AgBArF (1.2 equiv) | 10 | 3.8 | 4560 | 162.9 | 32 | 6.4 | 2.00 | 105.2 |
| 5f | AgBArF (1.2 equiv) | 5 | 3.2 | 7680 | 274.3 | 41 | 4.6 | 2.17 | 104.6 |
| 6 | B(C6F5)3 (10 equiv) | 10 | 2.4 | 2880 | 102.9 | 25 | 11.4 | 1.93 | 108.6 |
a
Conditions: 5 μmol of C1, 400 psi ethylene, 45 mL of toluene, 20 °C.
b
Determined by 1H NMR in D2-tetrachloroethane at 125 °C.
c
Determined by GPC in 1,2,4-trichlorobenzene at 160 °C using polystyrene calibration.
d
Determined by differential scanning calorimetry.
e
2 μmol of C1.
f
Included 10 equiv of B(C6F5)3. TOF = Turnover Frequency, Mn = Number-Average Molecular Weight, Đ = Dispersity, Tm = Melting Temperature.