Ethylene Polymerization through Neutral Nickel Complexes Bearing Cyclic Imides

Table 1

Ethylene polymerization results^a.

Entry	Temperature^b	Pressure	Yield^c	Activity ^d	Tm^e	Xc^e	Branches^f
Ni1-1	60	6	2.1	3.5	107	31.7	55
Ni1-2	60	8	2.4	4	112	34.2	62
Ni1-3	80	8	1.95	3.25	118	27.6	73
Ni2-1	60	6	1.42	2.36	118	44	22
Ni2-2	60	8	1.62	2.7	118	46	38
Ni2-3	80	8	1.23	2.05	118	41.3	47

^aGeneral conditions: Ni =30 μmol, toluene =100 ml, and time =2 h. ^bReaction temperature °C. ^cYield (g). ^dActivity  g PE mol Ni^-1 h^-1. ^eMelting temperature (°C) and crystallinity (%) provided by DSC. ^fBranching numbers per 1000C by NMR.