Polyethylene/Clay Nanocomposites Produced by In Situ Polymerization with Zirconocene/MAO Catalyst

Table 1

Catalytic activities of polymerization systems with various fillers.

Run	Polymer	Amount of clay (wt%)		Yield^a (g)	Activity^b (kg pol./mol Zr·h)
		Clay A	Clay B
1	PE	—	—	1.3643	17,588
2		5	—	0.6622	12,851
3		10	—	0.7083	8,730
4		20	—	0.5894	6,869
5		40	—	0	0
6		—	10	0.7937	8,007
7		—	20	0.2906	5,440
8		—	40	0	0
9	LLDPE	—	—	1.3087	35,534
10		5	—	1.1045	20,036
11		10	—	1.2241	12,143
12		20	—	0.3998	5,578
13		40	—	0	0

aThe polymer yield was limited by the amount of ethylene fed (0.018 mol). The molar ratio of ethylene: comonomer was 2 : 1.
bActivities were measured at polymerization temperature of 70°C, [ethylene] = 0.018 mol, [Al]_MAO/[Zr]_cat = 1135 in toluene with total volume = 30 mL, [Zr]_cat = 5 × 10⁻⁵ molar and mixing time of MAO and nanoclay was 30 min.