Multi-arm cationic star-polymers
US5395885A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 17, 1993 |
| Grant date | Mar 7, 1995 |
| Priority date | — |
| Expiry date | Dec 17, 2013 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F297/00
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The first synthesis of a multi-arm radial-star polyisobutylene is described. The synthesis occurred by the addition of excess divinylbenzene (DVB) linking reagent to a living polyisobutylene (PIB.sup..sym.), charge, i.e., by the "arm first" method under specific conditions. The radial structure of the star-PIB was proven by determining the molecular weight of a sample by light scattering, then selectively destroying the aromatic polydivinylbenzene core, and finally determining the molecular weight of the surviving aliphatic PIB arms. The synthesis strategy, kinetic observations during synthesis, and procedures leading to a representative star-PIB are described. This product whose M.sub.w =1,134,400 g/mole with M.sub.w /M.sub.n =2.83, contained .about.90.3 mole % (.about.78 wt. %) PIB arms and .about.9.7 mole % (.about.22 wt. %) aromatic core; thus the number of PIB arms emanating from the core was N.sub.n, arm =56 or N.sub.w, arm (weight average number of arms)=110.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.