Process for the preparation of industrially applicable difunctional anionic polymerization initiators and their use
US5554696A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 9, 1995 |
| Grant date | Sep 10, 1996 |
| Priority date | — |
| Expiry date | May 9, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F36/04
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Process for the preparation of an efficient industrial .alpha., .omega.-dilithio poly(conjugated diene) diinitiator having a peak molecular weight in the range of from 1000 to 3000, comprising the reaction of mono-organolithium initiator with diisopropenyl benzene in an apolar hydrocarbon solvent, optionally in the presence of a tertiary amine, followed by addition to the reaction mixture of a small amount of conjugated diene monomer and at least 15 vol % of an aromatic ether activator at a temperature in the range of from 0.degree. to 30.degree. C.; the use of said .alpha., .omega.-dithio initiator for the manufacture of symmetrical block copolymers by anionic polymerization, from monovinylaromatic, conjugated diene and/or polar vinyl compound monomers; and block copolymers so obtained having a combination of a narrow molecular weight distribution (Mw/Mn.ltoreq.1.20) and relatively low vinyl content (.ltoreq.18%).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.