Polyolefin Spheres from Metallocenes Supported on Noninteracting Polystyrene

• Published in: Science (American Association for the Advancement of Science) 1998-04, Vol.280 (5361), p.270-273
• Main Authors: Roscoe, Stephen B., Jean M. J. Fréchet, Walzer, John F., Dias, Anthony J.
• Format: Article
• Language: English
• Subjects: Amines; Anions; Applied sciences; Catalysts; Chemistry; Environment; Exact sciences and technology; Ligands; Metal particles; Observations; Organic polymers; Physicochemistry of polymers; Polymerization; Polymers; Polyolefins; Properties and characterization; Quaternary ammonium compounds; Resins; Salts; Scientific Concepts; Special properties (catalyst, reagent or carrier)
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.280.5361.270

To obviate the destructive interaction of highly reactive metallocene catalysts with classical silica-based supports while retaining the advantage of supported catalysts, a noninteracting polystyrene support was developed. Supported catalysts for the polymerization of α-olefins are prepared by treating lightly cross-linked, chloromethylated polystyrene beads consecutively with a secondary amine, an ammonium salt of a weakly coordinating anion, and a neutral dialkylmetallocene. Catalytic sites are distributed homogeneously throughout the support particle, and the polymerization occurs within the bead, in contrast to traditional surface-supported metallocene catalysts. The copolymerization of ethylene and 1-hexene at 40°C affords discrete spherical polyolefin beads with a size (0.3 to 1.4 millimeters) that varies according to the polymerization time.