Allied Chemical Corporation

Allied Corporation

Lester T Lee

Kang-Jen Liu

Win-Sow Ho

Frederick P Chlanda

Gerald J Dege

Dusan C Prevorsek

Gary A Harpell

Shaul M Aharoni

Gordhanbhai N Patel

Anthony F Preziosi

Himangshu R Bhattacharjee

George J Schmitt

Process of detecting the presence of certain gases, including certain pollutants, in small concentrations; or to cause partial polymerization of certain polyacetylene compositions for use in time/temperature history indicators or radiation dosage indicators. The process involves contacting a reactive gas, such as a nitrogen oxide, a halide or ozone, with a crystalline substituted acetylenic monomer containing at least two conjugated triple bonds and substituents having at least one atom of oxygen or nitrogen. In particular the acetylenic compound is 2,4-hexadiyne-1,6-bis(phenylurethane) crystallized from tetrahydrofuran or acetone.

Coloration of acetylenic monomers by gases

Stable single film bipolar membranes of prolonged life and improved performance particularly for use in electrodialysis water splitting process, are prepared by introducing a more stable interface in the membrane structure. After the cationic exchange groups are preformed on an insoluble cross-linked aromatic polymeric matrix, the dissociable anionic exchange groups may be introduced more intimately chemically bonded in position by using multi-functional compounds containing mixed tertiary, secondary and primary amine groups, so that the resulting interface is comparatively more stable, and is less likely to be neutralized, therefore, attaining longer life-time and a higher level of performance.

Stable high performance bipolar membrane with cross-linked functional

Partially unsaturated polymers are dissolved in a two component solvent comprising a first component having a reactivity toward ozone less than carbon-carbon double bonds but more reactive than carbon-carbon single bonds and a second component being inert toward ozone. Introduction of ozone into the solution produces ozonides which are readily cleft into difunctional aliphatic species that can be converted to e.g. carboxy-terminated or multifunctional carboxy substituted aliphatic compounds. These may be used as monomeric species in various polymerization schemes as such, in preparation of polyamides, for example, or may be reduced to aldehydes or alcohols to be used in the preparation of such polymers as polyesters, polyurethanes, poly (Schiff bases), etc. The carboxylated products may also be employed as ionomers, which are useful as surfactants. Monocarboxyl terminated polyethylene having a number average molecular weight of from about 4,000 to 100,000 are provided. Poly(carboxymethyl) substituted polyethylenes, wherein from about 0.05 to 1.3 percent of the hydrogen atom or polyethylene are substituted with carboxymethyl groups, are obtained.

Production of ozonides from unsaturated polymers

Superior bipolar membranes are prepared having high performances. The improvement is achieved by (1) using high performance component ion exchange membranes, and (2) controlling the method of joining two component membranes into a bipolar membrane. The method of preparation of high performance component ion exchange membranes is also disclosed.

Method of making novel two component bipolar ion exchange membranes

Stable bipolar membranes of high permselectivity and low potential drop are prepared using either an anion or cation preformed first layer upon which a second layer or coating of an ion exchange resin of the opposite charge carried in a matrix polymer is applied. The second layer may be suitably applied such as by casting as a slurry of the ion exchange resin in a solution or by laminating a layer comprising a dispersion of the resin in a solid or fused polymer. Optionally, the surface of the first layer may be treated to increase the resin concentration and/or bonding at the interface, such as by sanding, etching, etc.

Bipolar membranes and method of making same

Novel polyelectrolyte membranes of substantially improved efficiency and durability are prepared from a preswollen film containing a relatively high amount of an insoluble cross-linked aromatic polymer. By preswelling the insoluble matrix under controlled conditions preferably to an equilibrium stage, the dissociable ion-exchange groups may be introduced more uniformly onto the aromatic nuclei of the matrix to a desired depth of the film. Controlled penetration of functional groups is important in preparing high performance cationic, anionic membranes as well as bipolar membranes. The membranes so prepared have low electrical resistance, improved current efficiency, undergo negligible degradation and with excellent durability.

Preparation of high performance polyelectrolyte membrane

Improved novel single film bipolar membranes having an ion selectivity above 80% in an electrolyte medium of about one mole, are prepared containing a relatively high amount, i.e. at least 15% of an insoluble cross-linked aromatic polymer. Before the styrenated sheet is chemically functionalized, the film surface is specifically treated, i.e. cleaned to make it more receptive to functional groups, so that the cationic-exchange groups and anion-exchange groups can be introduced homogeneously from each side of the surface-cleaned film, and a single-film bipolar membrane of superior durability, stability, and quality control results.

High performance, quality controlled bipolar membrane

Novel cycloaliphatic diamines have been prepared which are consisting of two unequivalent amine groups. The diamines are prepared by reduction of aromatic dinitro compounds. The polyamides made from these diamines are useful in forming fibers and films having excellent high temperature properties.

Cycloaliphatic unsymmetrical diamines

A system utilizing membrane extraction is provided to recover metal values. The system may be used to separate metal ions from an aqueous solution through the membrane by an organic liquid containing a chelating agent. This invention also contemplates the recovery of metal values from an organic phase, containing the metal complexed with a chelating agent, by an aqueous phase using membrane extraction. In the former case, the metal ion is passed through the membrane from the aqueous phase to the organic phase where it forms a complex with a chelating agent present in the organic phase. In the latter case the metal is extracted from the organic phase into the aqueous phase through the membrane. In both cases a chelating exchange reaction is involved at the interface between the membrane and one of the two phases. This hydro-metallurgical process employs membranes with metal ion diffusivity in the range of about 10.sup..sup.-5 to about 10.sup..sup.-8 cm.sup.2 /sec. and has advantages over conventional metal extractions and may be applied as the mechanism is pollutant removal and recovery as well as for metallurgical separations.

Membrane hydro-metallurgical extraction process

A membrane solvent extraction system is utilized to separate two substantially immiscible liquids and extract a solute through a solvent swollen membrane from one solvent liquid phase to the extracting solvent liquid without direct contact between the liquid phases. The membrane extraction method has advantages over conventional solvent extraction and may be applied as the mechanism in separation, purification, pollutant removal and recovery processes.

Membrane solvent extraction

Novel membrane compositions are prepared from polymers comprising tertiary amine containing polyamideamine functional groups. The membranes are durable, highly selective and have excellent homogeneity and high diffusivity. Asymmetric membranes can be prepared by solution casting or melt processing techniques can be used to produce homogeneous, high performance, symmetric membranes. The specific compositions of the membranes can be adjusted so as to achieve a membrane possessing a required degree of hydrophilicity and porosity. These membranes may be used in a variety of separation applications, particularly in two-phase solvent extraction.

Novel high diffusivity membranes

Novel cross-linked interpolymer membranes of substantially improved efficiency and durability are prepared from a co-mixture of a hydrophilic polymer of [1, .omega.-alkylene(2,6-diketopiperazine)-1,4-dicarboxamide] and a hydrophobic polymer such as polyvinylidene fluoride, by dissolving these polymers in a suitable solvent, forming films of suitable thickness from the solution and thereafter preferably crosslinking the dissolved mixture.

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Parsippany, NJ, United States of America

Lester T Lee