Rheology modification of polymers prepared using metallocenes

US6528136B1 · kind B1 · utility

Assignee

• DOW GLOBAL TECHNOLOGIES LLC · US

Inventors

• Thoi H. Ho · Lake Jackson, US
• Wendy Hoenig · Lake Jackson, US
• Che-I Kao · Lake Jackson, US
• Michael E. Rowland · Lake Jackson, US
• Clark H. Cummins · Midland, US
• Michael J. Mullins · Lake Jackson, US
• H. Craig Silvis · Midland, US

Key dates

• Filing date: Aug 26, 1998
• Grant date: Mar 4, 2003
• Expiry date: Aug 26, 2018

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/31917
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The invention includes a process of preparing a coupled polymer comprising heating an admixture containing (1) at least one polyolefin comprising ethylene and optionally at least one comonomer which is selected from alpha olefins having at least 3 carbon atoms, dienes and combinations thereof said polyolefin having a molecular weight distribution of less than or equal to about 3 and (2) a coupling amount at least one poly(sulfonyl azide) to at least the decomposition temperature of the poly(sulfonyl azide) for a period sufficient for decomposition of at least about 80 weight percent of the poly(sulfonyl azide) and sufficient to result in a coupled polymer; particularly where the polyolefin is the product of polymerization of ethylene and optionally at least one other alpha-olefin in the presence of a single site catalyst (transition metal like Va or Cr, metallocene or constrained geometry). The amount of poly(sulfonyl azide) is preferably from about 0.01 to about 5 weight percent of the polyolefin. The poly(sulfonyl azide)and polyolefin preferably react at a temperature at least the decomposition temperature and greater than about 150° C. The invention also includes any composi…