685
Table 4 Properties of polypropylene obtained using different catalyst compositions [23]
Catalyst
Yield
a Fraction %
η inh
(dL/g)
T g
(°C)
T m
(°C)
ΔH f
(J/g) M n × 10
3 M w × 10
3
TNZ-Al 2 O 3
47.7 Total
100 10.2
−10.1 147.1 13.1
75.5
600
Ether
Sol.
28.2 3.81 −8.0 52.0 1.6
80.8
604
Hept.
Sol.
17.9 4.78 −7.8 130.2 27.7
39.3
934
Hept.
Insol.
50.0 15.3
−7.4 147.7 49.0
455
2626
TNZ/Al 2 O 3 + H 2
(5 psi)
92.7 Total
100 4.08 −11.5 151.8 5.0
34
370
Ether
Sol.
49.0 2.54 −8.8 53.0 1.8
22.3
261
Hept.
Sol.
33.0 3.28 −10.1 137.0 29.2
22
478
Hept.
Insol.
24.0 8.04 −7.5 149.9 68.7
108
3460
MgCl 2 /TiCl 4 /
AlEt 3
2680 Total
100 2.11 −394 159.6 62.5
22.4
128
Ether
Sol.
21.0 0.82 −3.6 nd
nd
19.1
66.8
Hept.
Sol.
19.3 0.78 −1.6 140.1 63.0
28
110
Hept.
Insol.
53.0 3.45 nd
166.3 102.0 160
531
MgCl 2 /TiCl 4 /
AlEt 3 + H 2 (5
psi)
2140 Total
100 0.53 −9.8 159.0 78.2
12.1
42.3
Ether
Sol.
26.6 0.31 −10.4 Nd
nd
6.7
16.5
Hept.
Sol.
24.5 0.28 −1.8 156.4 63.5
10
26.7
Hept.
Insol.
45.7 0.83 nd
161.3 105.0 26.8
110
The polymerization was carried out in heptane at 60–65 °C for 1 h
TNZ tetraneophylzirconium
a g/mmol of metal
ZrCl 2
C5 SYMMETRIC
C2 SYMMETRIC
ZrCl 2
(a)
(b)
Zr
(c)
Cl
Cl
C2 SYMMETRIC
Fig. 6 Structures of the stereorigid (a) C 2 -symmetric, (b) C 5 -symmetric, and (c) unbridged C 2 -
symmetric metallocene catalysts
Evolution of Ziegler-Natta Catalysts for Polymerization of Olefins
Table 4 Properties of polypropylene obtained using different catalyst compositions [23]
Catalyst
Yield
a Fraction %
η inh
(dL/g)
T g
(°C)
T m
(°C)
ΔH f
(J/g) M n × 10
3 M w × 10
3
TNZ-Al 2 O 3
47.7 Total
100 10.2
−10.1 147.1 13.1
75.5
600
Ether
Sol.
28.2 3.81 −8.0 52.0 1.6
80.8
604
Hept.
Sol.
17.9 4.78 −7.8 130.2 27.7
39.3
934
Hept.
Insol.
50.0 15.3
−7.4 147.7 49.0
455
2626
TNZ/Al 2 O 3 + H 2
(5 psi)
92.7 Total
100 4.08 −11.5 151.8 5.0
34
370
Ether
Sol.
49.0 2.54 −8.8 53.0 1.8
22.3
261
Hept.
Sol.
33.0 3.28 −10.1 137.0 29.2
22
478
Hept.
Insol.
24.0 8.04 −7.5 149.9 68.7
108
3460
MgCl 2 /TiCl 4 /
AlEt 3
2680 Total
100 2.11 −394 159.6 62.5
22.4
128
Ether
Sol.
21.0 0.82 −3.6 nd
nd
19.1
66.8
Hept.
Sol.
19.3 0.78 −1.6 140.1 63.0
28
110
Hept.
Insol.
53.0 3.45 nd
166.3 102.0 160
531
MgCl 2 /TiCl 4 /
AlEt 3 + H 2 (5
psi)
2140 Total
100 0.53 −9.8 159.0 78.2
12.1
42.3
Ether
Sol.
26.6 0.31 −10.4 Nd
nd
6.7
16.5
Hept.
Sol.
24.5 0.28 −1.8 156.4 63.5
10
26.7
Hept.
Insol.
45.7 0.83 nd
161.3 105.0 26.8
110
The polymerization was carried out in heptane at 60–65 °C for 1 h
TNZ tetraneophylzirconium
a g/mmol of metal
ZrCl 2
C5 SYMMETRIC
C2 SYMMETRIC
ZrCl 2
(a)
(b)
Zr
(c)
Cl
Cl
C2 SYMMETRIC
Fig. 6 Structures of the stereorigid (a) C 2 -symmetric, (b) C 5 -symmetric, and (c) unbridged C 2 -
symmetric metallocene catalysts
Evolution of Ziegler-Natta Catalysts for Polymerization of Olefins