Microcapsules for use in artificial kidney machines

Claim 2

SUBSTANTIALLY SPHERICAL MICROCAPSULES OF DIAMETER BETWEEN ABOUT 10$ AND 5 MM, CONSISTING ESSENTIALLY OF A CROSSLINKED POLYMER CONTAINING SULPHONIC ACID GROUPS AND POSSESSING A THEORETICAL EXCHANGE CAPACITY GREATER THAN ABOUT 0.5 MEQ/G OF DRY POLYMER HAVING A SKIN COATING OF A COATING POLYMER CONTAINING QUATERNARY AMMONIUM GROUPS BONDED BY AT LEAST ONE COVALENT BOND TO THE CHAIN OF SAID COATING POLYMER, THE POLYMER POSSESSING A PERMEATION SELECTIVITY GREATER THAN ABOUT 65 PERCENT AND A WATER ABSORPTION OF BETWEEN ABOUT 2 AND 50 PERCENT, THE THICKNESS OF THE SKIN BEING ABOUT 0.1 TO 20 PERCENT OF THE RADIUM OF THE MICROCAPSULE.

Claim 3

Microcapsules according to claim 1 in which the polymer containing sulphonic acid groups consists essentially of: a. 50 to 90 percent by weight of units of the formula:

Claim 4

Microcapsules according to claim 2 in which the divalent radicals which R'' may represent contain at most 6 halogen atoms and at most 6 OH groups.

Claim 5

Microcapsules according to claim 2 in which R4 represents an alkoxyaryl or aralkoxy radical, the aryl radical being phenyl and the alkoxy radical containing at most 6 carbon atoms.

Claim 6

Microcapsules according to claim 2 in which the symbol . represents an alkylene or alkenylene radical with at most 6 carbon atoms, or said radical containing at least one chain -O-, -S-, -NH-, -SO2- or -C6H4- group, or a simple phenylene radical, or said radicals optionally being substituted by -SO3H.

Claim 7

Microcapsules according to claim 1 in which the sulphonated polymer is a sulphonated styrene/divinyl benzene copolymer.

Claim 8

Microcapsules according to claim 1 in which the polymer forming the skin is the reaction product of: a. a polymer comprising a plurality of units of the formula:

Claim 9

Microcapsules according to claim 7 in which the polymer forming the skin comprises 15 to 40 percent of units of formula (VII) and 85 to 60 percent of units of formula (III).

Claim 10

Microcapsules according to claim 7 in which the polymer forming the skin is the reaction product of a polymer containing a plurality of units of formula (VII) and units of formula (III), at least a part of the units of formula (III) carrying reactive groups other than tertiary amino groups, with a monoquaternising or a polyquaternising compound or mixtures thereof, and with a polyfunctional agent which reacts with the reactive groups of the units of formula (III).

Claim 11

Microcapsules according to claim 1 in which the polymer forming the skin is the reaction product of: a. a polycondensate comprising a plurality of units of the formula:

Claim 12

Microcapsules according to claim 10 in which the units possessing tertiary nitrogen atoms are as follow: in the case of Q and T2: an alkylene radical containing 2 to 12 carbon atoms, a cycloalkylene radical with five or six ring carbon atoms, or an arylene radical, substituted by a dialkylamino radical; a radical consisting of 2 of said alkylene or arylene radicals joined by an alkylimino group; or a heterocyclic structure with 5 or 6 ring members, containing 1 or 2 nitrogen atoms and no other hetero-atom, said nitrogen atom or one of said atoms being bonded by its three valencies to adjacent carbon atoms or by two valencies to adjacent carbon atoms and by the third to an alkyl radical of 1 to 4 carbon atoms, in the case of T1: a linear or branched aliphatic hydrocarbon radical containing 2 to 12 carbon atoms, which may be saturated or possess ethylenic or acetylenic unsaturation and which is substituted solely, or at least, by a dialkylamino radical, or a radical consisting of 2 of said aliphatic radicals connected by an alkylimino radical, the alkyl groups of the dialkylamino and alkylimino radicals having 1 to 4 carbon atoms.

Claim 13

Microcapsules according to claim 11 in which Q or T2 or both represents a cycloalkylene radical with 5 or 6 ring carbon atoms or a phenylene radical, substituted by a dialkylamino radical of 1 to 4 carbon atoms.

Claim 14

Microcapsules according to claim 10 in which the sKin is the reaction product of a polycondensate comprising a plurality of units of formulae (VIII) or (IX) of which some possess bonds of an olefinic nature, with, firstly, a monoquaternising or a polyquaternising compound or mixtures thereof and, secondly, with a polyunsaturated compound which is capable of reacting with the ethylenic double bonds present in the polycondensate.

Claim 15

Microcapsules according to claim 10 in which the polycondensate is a polycondensate containing blocks of units of formula (VIII) connected by groups of the formula:

Claim 16

Microcapsules according to claim 1, in which the polymer forming the skin is the reaction product of a polymer comprising a plurality of units of the formula: a. - Delta -E-(XII) in which Delta represents an organic radical carrying a halogen substituent and each of the E radicals, which may be identical or different, represents -O-, -SO2- or -(CH2)v-group, v being from 1 to 4, or units which do not carry halogen atoms, with b. a tertiary monoamine or a compound carrying several tertiary amino groups.

Claim 17

Microcapsules according to claim 15, in which the polymer of formula (XII) is the reaction product of a chloromethylating agent with a polymer of the formula: - Delta '' - E- (XIII) in which Delta '' represents a p-phenylene radical, which may optionally be substituted by one or two alkyl radicals with 1 to 4 carbon atoms or by one or two phenyl radicals or a radical of the formula:

Claim 18

Microcapsules according to claim 15 in which the polymer of formula (XII) is the reaction product of an epihalohydrin with a hydroxylic polymer consisting of a plurality of units of the formula:

Claim 19

Microcapsules according to claim 1 in which the polymer forming the skin is derived from a dimethylaminoethyl methacrylate/acrylonitrile, 2-vinyl-5-methylpyridine/acrylonitrile or epichlorohydrin/bisphenol A copolymer.