Prevention of PVC polymer buildup in polymerization reactors using oxalyl bis(benzylidenehydrazide) and alumina
US4145496A · kind A · utility
3Cited by
1References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 3, 1978 |
| Grant date | Mar 20, 1979 |
| Priority date | — |
| Expiry date | Jul 3, 1998 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F2/004
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Polymer buildup in polymerization reactions during vinyl chloride polymerizations is greatly reduced by applying a water dispersion of alumina and oxalyl bis(benzylidenehydrazide) (OABH) to the reactor surfaces exposed to the polymerization medium prior to carrying out the polymerization. Long term effects of the buildup preventor can be obtained by applying a caustic wash to the reactor walls, prior to applying the oxalyl bis(benzylidenehydrazide) and alumina dispersion. The effect of the OABH/alumina and caustic is synergistic since the preventative effect is greater than either material used alone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.