Synthesis of styrene-isoprene rubber
US6313216A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 1, 2000 |
| Grant date | Nov 6, 2001 |
| Priority date | — |
| Expiry date | Sep 1, 2020 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F236/10
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
This invention discloses a process for synthesizing random styrene-isoprene rubber comprising: (1) continuously charging isoprene, styrene, an initiator, and a solvent into a first polymerization zone, (2) allowing the isoprene and styrene to copolymerize in the first polymerization zone to total conversion of 60 to 95 percent to produce a polymer cement containing living styrene-isoprene chains, (3) continuously charging the polymer cement containing living styrene-isoprene chains and additional isoprene monomer into a second polymerization zone, wherein from 5 to 40 percent of the total amount of isoprene changed is charged into the second polymerization zone, (4) allowing the copolymerization to continue in the second polymerization zone to a conversion of the isoprene monomer of at least 90 percent wherein the total conversion of styrene and isoprene in the second polymerization zone is limited to a maximum of 98 percent, (5) withdrawing a polymer cement of random styrene-isoprene rubber having living chain ends from the second reaction zone, (6) killing the living chain ends on the random styrene-isoprene rubber, and (7) recovering the random styrene-isoprene rubber from the p…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.