Ceskoslovenska Akademie Ved

Akademia Nauk Sssr

Akademija Nauk Sssr

Miroslav Bleha

Zdenek Plichta

Frantisek Svec

Boris G Belenkii

Eva Votavova

Tatiana B Tennikova

Jaroslav Kalal

Jan Lokaj

Galina A Polockaja

Kira A Romaskova

Jurij P Kuznecov

Jan Schauer

Highly selective membranes for the separation of mixtures He/N.sub.2 and O.sub.2 /N.sub.2, which have suitable mechanical properties and high permeability are dislcosed. They consist of a polymeric porous base from poly-2,6-dimethyl-1,4-phenyleneoxide and a polymeric selective layer formed from polyamidoimide of the general formula I, where R= ##STR1## and n=140-220 ##STR2## or from an interpolymeric equimolar complex of PAI-1 with polyvinylpyrrolidone, or from an aromatic polyimide of the general formula II, where X is --O-- or ##STR3## and n=150-230 ##STR4## or of the general formula III, where n=150-240 ##STR5## or from polymeric imides of the general formula IV, where R=H or CH.sub.3 ##STR6## or also from their copolymers with styrene, methyl methacrylate, methyl acrylate, and dimethylaminoethyl methacrylate. A method for the preparation of composite polymeric membranes consists of saturation of the porous base from poly-2,6-dimethyl-1,4-phenyleneoxide with an organic solvent inert to it, e.g. with C.sub.7 H.sub.16 to C.sub.10 H.sub.22 aliphatic hydrocarbons or their mixtures, drying, and coating with a 1-25 wt.-% solution of the selective polymer in an organic solvent which is incompatible with the organic liquid, e.g. N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide or their mixtures.

Composite polymeric membranes for the separation of mixtures of gases

A method for preparation of macroporous polymeric membranes consisting in placing a mixture of monomers and a radical initiator, dissolved in a porogenic inert organic solvent selected from the group comprising alcohols, estes of carboxylic acids, ketones, and their mixtures, into a space of an adapted shape formed by two temperature-controlled plates and a distance insert having the thickness corresponding to the required thickness of membrane and heating up to 80.degree. C. for 24 hours at utmost in order to carry out the radical polymerization. Azo-bis-isobutyronitrile is advantageously used as an initiator in the amount 0.05-2 wt. % related to monomers in the polymerization mixture. Cyclohexanol or its mixture containing up to 20 vol. % dodecanol are advantageously used as a porogenic solvent in the amount 40-60 vol. % in the polymerization batch. Also included is the method of application of macroporous membranes, where a sector made from the membrane is placed on a base fixing its position and enabling the outlet of liquid passing through the membrane, which base create a wall of a chamber. The chamber is filled with a solution of polymer or polymer mixture, the solution passes through the membrane under pressure up to 1 MPa, the polymer or polymers are sorbed in the membrane, and then a solvent with properties changing according to the purposeful program is introduced into the chamber and individual components of the separated mixture are eluted and detected and/or collected.

Macroporous polymeric membranes for the separation of polymers and a

An object of the invention are macroporous polymeric membranes, suitable above all for the separation of polymers, which consist of the copolymer of a monovinyl monomer, selected from the group comprising acrylates, methacrylates, vinylpyridine, N-vinylpyrrolidone, vinyl acetate, and hydroxystyrene, with a divinyl monomer, selected from the group comprising alkylene and hydroxyalkylene diacrylates and dimethacrylates, divinylbenzene, and divinylpyridine, at the ratio of monomers of both types ranging from 5:95 to 95:5 wt.%. The membranes are formed from polymeric globular entities which have the size 0.05 to 0.05 .mu.m and are interconnected by covalent bonds, whereas communicating voids - pores occur between the globuli. The total thickness of membranes is 0.2 to 15 mm and their specific surface area, which is measurable also in the dry state, may attain 400 m.sup.2 /g. Glycidyl methacrylate is advantageously used as the monovinyl monomer in the amount 5-80 vol.% related to the total volume of monomers. Ethylene dimethacrylate is advantageously used in the amount 20-95 vol.% related to the volume of monomers as the divinyl monomer. The membranes contain on their inner surface covalently bound allyl, hydroxyl, amine, sulfonate, hydrogensulfonate, thiol, and/or alkyl groups containing up to 18 carbon atoms and may be reinforced in their whole cross-section with an insert.

Polymers containing a reactive aromatic system in the side chain which consist of structural units of the general formula IV: ##STR1## where R.sup.1 is hydrogen or CH.sub.3,

Polymers containing a reactive aromatic system based on

Polymeric color pH indicators are prepared which are insoluble in the measured aqueous medium and show a certain range of color change. These polymeric indicators are the product of copolymerization of a hydrophilic comonomer, selected from esters, amides and N-substituted amides of acrylic and methacrylic acid, with 0.1- 30 wt.% of a comonomer. The comonomer forms the pH-indicating color center by a subsequent coupling with a suitable diazonium salt or a passive component. Vinylic monomers comprising an aromatic system in the molecule are suitable as the functional comonomers. The indicators are prepared by radical copolymerization of the comonomers either in a suspension or in a solution, followed by the subsequent coupling with a diazonium compound, or diazotizing and coupling with a passive component, to obtain the pH-indicating sites of polymer. The product is in the form of small spherical macroporous particles suitable for pH indication in flow-through column processes, in small volumes, or on a microscope stage, or in the form of a solution applicable as a paint and indicating the pH of vessels, reactors, etc. coated therewith, or useful for application to inert carriers.

Polymeric color indicators and a method of their preparation

The invention relates to monomers of the general formula I with a reactive aromatic system based on p-phenylenediamine derivatives:

Monomers and polymers containing the reactive aromatic system and method

The invention relates to biologically active insoluble compounds on a carrier containing in its side chains a p-phenylene-diamine skeleton, where a polymer of the general formula I ##STR1## where R.sub.1 is a polymer residue, R.sub.2 is a lower alkyl group, x = 1-4, is oxidized in the presence of a soluble biologically active compound containing a primary amino group, such as e.g. enzymes, coenzymes, inhibitors of enzymes, hormones, or antigens. The oxidation is carried out by using an oxidation agent which does not disturb the biologically active compounds present in the mixture.

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Prague, Czechia

Miroslav Bleha