Akzo N.v.

Basf Se Corporation

Akzo Nobel N.v.

Akzona Incorporated

Michael Diamantoglou

Gerhard Meyer

Walter Brodowski

Gustav Dunweg

Helmut Magerlein

Thomas Rintelen

Ulrich Baurmeister

Werner Henne

Michael Pelger

Helmut Schulze

Horst-Dieter Lemke

Ernst F Kundinger

Christoph Josefiak

Helmut Kuhne

Hans Georg Tilgner

Alexander Brandner

Martin Nywlt

Gustav Duweg

Angelika Reiche

Winfried Holz

Edmund Richter

Wolfgang Grimm

Christoph Hartmann

Ralf Tatas

The present invention relates to a method for producing polymers that are suitable for absorbing and storing aqueous liquids, and to polymers that can be obtained by this method. This invention further related to the use of such polymers. The method comprises the following steps:

Highly swellable polymers

A method for producing cellulosic dialysis membranes in the form of flat, tubular, or hollow fiber membranes by spinning a spinning solution of cellulose and/or modified cellulose, a tertiary amine oxide, and additional liquids and additives such as stabilizers, pore formers and the like is provided. The method operates at high takeoff speed and produces membranes for the low, middle, and high flux ranges. The membranes show practically no aging and have a stable structure. The oxidative breakdown of cellulose in the manufacture of the membranes is extremely low and hemocompatability is very good.

Method of making cellulosic dialysis membrane

A dialysis membrane for hemodialysis in the form of sheet films, tubular films, or hollow fibers is composed of a polysaccharide ether. The polysaccharide ether has a structure given by the formula ##STR1## in which cell is the skeleton of the unmodified cellulose molecule or of the chitin molecule, each with no hydroxyl groups, s is equal to 3 for the unmodified cellulose molecule and 2 for the chitin molecule, and x is the degree of etherification, which is in the range from 0.001 to 0.079, and R is an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl, arylalkyl, arylalkenyl, and/or arylalkynyl group with 3 to 25 carbon atoms, and/or the radical of a heterocyclic compound with 3 to 25 carbon atoms, in which the carbon chain may be interrupted by oxygen or sulfur atoms.

Dialysis membrane composed of polysaccharide ether II

A process for improving the biocompatibility of cellulosic film membranes is characterized by the fact that the film membranes are coated during or after their preparation with cellulose ethers and/or cellulose esters and/or cellulose carbamates whose structures conform to the formulas ##STR1## wherein Cell is the skeleton of the unmodified cellulose molecule without hydroxyl groups; x conforms to the degree of modification, which is in the range of 0.002 to 3; R is an (optionally substituted) alkyl and/or alkenyl and/or aryl and/or arylalkyl group and the carbon chain of the group R contains 1 to 36 carbon atoms and may be interrupted by hetero atoms such as O, S, N, and contains basic and/or acidic groups such as 13 NR'.sub.2, --COOR', and/or --SO.sub.3 R' or their salts, wherein R'=H or R.

Method for coating cellulosic membranes

Dialysis membrane for hemodialysis in the form of membrane films, tubular films, or hollow filaments made of polysaccharide ethers, are characterized by the fact that the polysaccharide ether has a structure shown by the formula ##STR1## in which Cell is the skeleton of the unmodified cellulose molecule or of the chitin molecule, without hydroxyl groups in each case, s is 3 in the unmodified cellulose molecule and 2 in the chitin molecule, and x corresponds to the degree of etherification, which is in the range from 0.08 to (s-0.4).

Dialysis membrane made of polysaccharide ether

Method of manufacturing deoxycellulose compounds from cellulose in aprotic solvents with LiCl and/or CaCl.sub.2, with the solvent, in addition to LiCl or CaCl.sub.2, additionally containing bromides, iodides, rhodanides, or dithiocarbamates of the alkaline and/or alkaline earth metals, and the cellulose initially being dissolved in the mixture of aprotic solvent and salts, with a base and/or a basic salt being added at room temperature, and a sulfonic acid halide being added corresponding to the desired degree of substitution, and then being caused to react at temperatures between 16.degree. C. and 100.degree. C.

Method of manufacturing deoxycellulose compounds

A modified cellulose and/or chitin for biocompatible dialysis membranes having a structure represented by the formula ##STR1## wherein cell is unmodified cellulose or chitin, in each case without hydroxyl groups, s=3 in the case of cellulose and s=2 in the case of chitin, R' is CH.sub.3 and/or C.sub.2 H.sub.5 and/or C.sub.3 H.sub.7, X denotes specified functional groups, m=0.75 to 2.85, and x=0.005 to 2.10. A process for preparation of the cellulose and/or chitin derivatives is also disclosed.

Modified chitin for biocompatible dialysis membranes II and process for

A modified cellulose and/or chitin for biocompatible dialysis membranes having a structure represented by the formula ##STR1## wherein cell is cellulose or chitin, in each case without hydroxyl groups, s=3 in the case of cellulose and s=2 in the case of chitin, R' is CH.sub.3 and/or C.sub.2 H.sub.5 and/or C.sub.3 H.sub.7, X denotes specified functional groups, R' is H or R, R'' denotes R, x+t=0.75 to 2.85, t=0 to 2.85, x=0 to 2.85, and r=0 to 1. A process for preparation of the cellulose and/or chitin derivatives is also disclosed.

Modified chitin for biocompatible dialysis membranes III and process for

A modified cellulose and/or chitin for biocompatible dialysis membranes having a structure represented by the formula ##STR1## wherein Cell is cellulose or chitin, in each case without hydroxyl groups, s=3 in the case of cellulose and s=2 in the case of chitin, R' is CH.sub.3 and/or C.sub.2 H.sub.5 and/or C.sub.3 H.sub.7, X denotes specified functional groups, R' is H or R, Z corresponds to the following groups of atoms: SR', SO.sub.3 H and salts thereof, SO-R, SONR'.sub.2, SO.sub.2 -R, SO.sub.2 NR'.sub.2, SO.sub.2 H and salts thereof, F, Cl, Br, I, NR'.sub.2, PR'.sub.2, PO.sub.3 H.sub.2 and salts thereof, PO.sub.2 H(OR), PO(OR).sub.2, PO.sub.2 HR' and salts thereof, POR'(OR) and POR'.sub.2, x+t=0.75 to 2.85, t=0 to 2.85, x=0 to 2.85, and z=0.01 to 0.45. A process for preparation of the cellulose and/or chitin derivatives is also disclosed.

Modified chitin for biocompatible dialysis membranes IV and process for

A biocompatible dialysis membrane for hemodialysis in the form of flat sheets, tubular sheets or hollow filaments is disclosed. The dialysis membrane comprises a mixed polysaccharide ester of acetic acid, and/or propionic acid and/or butyric acid and has a structure represented by the formula ##STR1## wherein Cell denotes the skeleton of the polysaccharide molecule without hydroxyl groups; a, b, p, and s are numbers wherein s is a maximum degreee of substitution and the following equations are satisfied: ##EQU1## with the provision that, if a=0, then p and b must be greater than 0 and, if p or b=0, then a must be greater than 0.

Biocompatible dialysis membrane comprising a mixed polysaccharide ester

Cellulosic membranes, characterized by the fact that a mixture of cellulose and compounds of the type

Cellulosic membranes

A cellulose derivative comprising substitution-modified cellulose regenerated from a cuprammonium solution, the substituents being ester groups, wherein the acyl group represents one or more, optionally substituted, carbon chains with 10-36 carbon atoms, or a residue containing at least one aromatic and/or heterocyclic, optionally substituted, ring, or wherein the substituents are carbamate groups, the carbamoyl group of which represents a group containing one or more, optionally substituted, carbon chains with 2-36 carbon atoms, or a group containing at least one aromatic and/or heterocyclic, optionally substituted, ring. A dialysis membrane made from the substitution-modified cellulose, typically in the form of a flat film, a tubular film, or a hollow filament, is also disclosed.

Cuprammonium-stable cellulose esters and carbamates for dialysis

A modified cellulose has a structure represented by the formula ##STR1## Cell is the framework of the unmodified cellulose molecule or of the chitin molecule, in each case without hydroxyl groups. Z is a nitrogen or sulfur atom. In the case where Z is a nitrogen atom, T and Z together are an acylamide or urea group and Q is (X'-Y') and/or together with the O an ester group and/or together with the O a carbamate group. In the case where Z is a sulfur atom, T is omitted and Q together with the O is an ester group and/or together with the O a carbamate group and, as desired, (X'--Y'). The relationships 0&lt;n&lt;m and 0.ltoreq.s&lt;m are obeyed and (n+s) indicates the mean degree of substitution. m=3 in the case of the unmodified cellulose molecule and m=2 in the case of the chitin molecule. As desired, --X-- can be omitted or --X-- and --X'-- denote specific divalent groups and --Y and --Y' denote --H and/or specified univalent radicals and X is identical to or different from X' and Y is identical to or different from Y' .

Modified cellulose for biocompatible dialysis membranes

Cellulose derivatives are disclosed which have the following formula: ##STR1## wherein Z is selected from the group consisting of alkylene, alkenylene, alkynylene, cycloalkylene or benzylene or xylylene radicals, which may or may not be substituted;

Cellulose derivatives and fibers and membranes made therefrom

A modified cellulose for biocompatible dialysis membranes having a structure represented by the formula ##STR1## wherein cell is cellulose or chitin, in each case without hydroxyl groups, s=3 in the case of cellulose and s=2 in the case of chitin, R' is CH.sub.3 and/or C.sub.2 H.sub.5 and/or C.sub.3 H.sub.7, X denotes specified functional groups, R' is H or R, R'' denotes R, x+t=0.75 to 2.85, t=0 to 2.85, x=0 to 2.85, and r=0 to 1. A process for preparation of the cellulose derivatives is also disclosed.

Growing community of inventors

Erlenbach, Germany

Michael Diamantoglou