Membranes of diisocyanate addition polymers for hemodialysis and/or hemofiltration
US4767535A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 25, 1986 |
| Grant date | Aug 30, 1988 |
| Priority date | — |
| Expiry date | Aug 25, 2006 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G18/4833
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Membranes are disclosed which are suitable for hemodialysis and/or hemofiltration, prepared from aliphatic diisocyanates, particularly cycloaliphatic diisocyanate such as cyclohexane diisocyanate-(1,4), particularly the transisomer and at least one compound which displays two active hydrogen atoms. For the reaction a molar ratio of soft segment to hard segment from 0 to 0.20, particularly from 0 to 0.1, is employed. Serving particularly for construction of the hard segments are compounds such as hydrazine, ethylene diamine, ethylene glycol and butanediol-(1,4). It is recommended to prepare the addition polymer in the presence of a aprotic solvent and a dissolving coagent such as lithium chloride or calcium chloride. Polyethers such as polyethylene glycol are particularly suitable for construction of the soft segment. The membrane is characterized by an ultrafiltration rate of from 0.5 to 300, particularly 0.5 to 100 ml/h.m.sup.2.Torr, and a dialytic permeability for vitamin B.sup.12 of 0.5 to 20.10..sup.-3 cm./min.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.