Low molecular weight high-cis polybutadienes and their use in high molecular weight-low molecular weight high-cis polybutadiene blends
US6437205B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 10, 2000 |
| Grant date | Aug 20, 2002 |
| Priority date | — |
| Expiry date | Jul 10, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/86
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for polymerizing 1,3-butadiene into a low molecular weight high-cis polybutadiene is described using a catalyst system comprising: (a) a neodymium-containing compound, (b) an aluminoxane or a trialkyl aluminum compound, (c) an organoaluminum hydride, and (d) a halogen source. A blend of a high molecular weight high-cis polybutadiene and the low molecular weight high-cis polybutadiene is also disclosed for use in pneumatic tire treads. Desirably both the high and the low molecular weight polymers have high cis contents, with the low molecular weight polymer being at least 70 percent cis and the high molecular weight polymer being at least 92 percent cis. Desirably both polymers are made with a neodymium catalyst system. The blends provide a balance of properties including good snow traction, wet traction, and rolling resistance while providing a balance of good physical properties including tension at break, modulus etc.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.