Qiang HUANG, He-fei CHANG, Shang-tao CHEN, Liao-yun ZHANG, Wei-huan HUANG, Hua-yi LI. The Effect of the C/N Mixed External Donors on the Microstructure of Polypropylene Prepared by Ziegler-Natta Catalyst[J]. Polymer Bulletin, 2012,25(11):63-68.
Qiang HUANG, He-fei CHANG, Shang-tao CHEN, Liao-yun ZHANG, Wei-huan HUANG, Hua-yi LI. The Effect of the C/N Mixed External Donors on the Microstructure of Polypropylene Prepared by Ziegler-Natta Catalyst[J]. Polymer Bulletin, 2012,25(11):63-68.DOI:
The effect of the C/N mixed external donors on the crystallization behavior and the isotactic sequence distribution of polypropylene prepared by a MgCl
2
-supported TiCl
4
Ziegler-Natta catalyst were studied through the SSA and
13
C-NMR techniques. When the ratio of the mixed external donors/Ti (Si/Ti) is kept in a constant
the different relative amount of the mixed external donors has an important effect on the isotactic sequence length distribution of polypropylene. The SSA results show that the crystallization ability and the relative contents of highest isotactic component gradually increase with the rise of the relative component of Donor-C in the mixed external donors
and the thickness distribution of lamellar becomes broader
indicating the isotactic sequence length distribution of polypropylene gets broader. In addition
the
13
C-NMR results show that the average isotactic sequence length and the average meso isotactic sequence length (MSL) of polypropylene gradually increase with the rise of the relative component of Donor-C in the mixed external donors
which shows a good correspondence between the SSA and