Porous regenerated cellulose membrane and process for the preparation thereof
US4581140A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 19, 1982 |
| Grant date | Apr 8, 1986 |
| Priority date | — |
| Expiry date | Nov 19, 2002 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L1/06
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A porous regenerated cellulose membrane consisting essentially of cellulose molecules having a viscosity average molecular weight of at least about 5.times.10.sup.4, the crystalline region of the cellulose molecules being substantially cellulose II crystal, cellulose III-2 crystal or the mixture thereof and having a degree of crystal orientation at a face of (101) in the crystalline region in the direction of the surface of the membrane of at most about 40%, the membrane having a dynamic modulus at 30.degree. C. measured with a frequency of 110 Hz of at least about 1.5.times.10.sup.8 (100-pr.rho.) dyn/cm.sup.2 wherein Pr.rho. is a porosity by percentage, a mean pore size represented by D(.mu.m) of about 0.01 .mu.m to about 20 .mu.m and at the same time a porosity in a plane of at least one plane of at least about 30% or a number of pores in a plane per 1 cm.sup.2 of about 6.times.10.sup.5 /D to about 3.times.10.sup.7 /D; and a process for preparing the same.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.