New Quenching Procedure for Preservation of Initial Polymer/Catalyst Particle Morphology in Ziegler-Natta Olefin Polymerization

• Published in: Macromolecular reaction engineering 2009-10, Vol.3 (8), p.467-472
• Main Authors: Thang, Vu Quoc, Taniike, Toshiaki, Umemori, Masaki, Ikeya, Mitsuhiro, Hiraoka, Yuichi, Nghia, Nguyen Duc, Terano, Minoru
• Format: Article
• Language: English
• Subjects: morphology; polyolefins; stopped-flow method; Ziegler-Natta polymerization
• ISSN: 1862-832X; 1862-8338
• DOI: 10.1002/mren.200900030

Preservation of initial polymer/catalyst particle morphology under air, was examined using stopped‐flow Ziegler–Natta polymerization with various quenching conditions and post‐chemical treatments. The exposure of the initial particles to air caused the fast formation of cracks on the surface, finally leading to significant reformation of the particle shape, when polymerizing particles were washed with heptane at −65 °C under N2 or under CO2. On the other hand, when the particles were washed with heptane containing an appropriate amount of tetrahydrofuran under CO2, the particle morphology under air was almost completely maintained even after 1 h exposure. The present results are useful for various ex situ characterizations of unstable initial polymer/catalyst particles. A new quenching procedure for the stopped‐flow Ziegler–Natta polymerization was established for the preservation of the polymerizing particle morphology in order to study the very initial stage of olefin polymerization. The established procedure enabled almost perfect preservation of the morphology even after 1 h exposure to air.