Abstract: The present invention relates to an improved design for a spiral wound membrane separation device. The improved module has one feed pipe separated into compartments which are connected axially to a porous spacer surrounded by a membrane envelope. A separate permeate pipe is immediately adjacent and generally in a parallel configuration to the fluid feed pipe and is in fluid communication with a different porous spacer sheet. When the porous feed membrane and pipe and spacer and permeate pipe are combined using appropriate complementary shaped spaced filling means, a spiral wound membrane separation device is obtained having two centrally located pipes. In one aspect, the membrane separation module further includes means for the addition of a countercurrent or cocurrent sweep fluid (gas) the permeate.

Abstract: Novel sulfonated polyamide and polyurea materials are described. The polymers are water-soluble or water-dispersible, if not crosslinked. The polymers can be crosslinked with polyvalent cations or crosslinking agents. The polymers have utility as membranes, thickeners, coatings and adhesives.

Abstract: A process for the separation of water from water-miscible organic compounds, comprising contacting a mixture of water and an organic compound against one side of a membrane comprising a salt of an anionic polysaccharide or blends thereof with a noncellulosic polyanion, and withdrawing at the other side of said membrane a mixture having a higher concentration of water.

Abstract: Novel sulfonated polyamide and polyurea materials are described. The polymers are water-soluble or water-dispersible, if not crosslinked. The polymers can be crosslinked with polyvalent cations or crosslinking agents. The polymers have utility as membranes, thickeners, coatings and adhesives.

Abstract: Asymmetric membranes are prepared by treating a major surface of a glassy polymer composition to render the surface resistant to solvent crazing and then contacting the glassy polymer composition with a crazing solvent. The crazing solvent permanently deforms the glassy polymer composition by forming a microporous structure on the untreated surface. The treated surface becomes the dense, discriminating layer of the membrane which achieves desirable permeation selectivity. The methods of treatment are (1) crosslinking, (2) providing an agent which renders the surface resistant to crazing, and (3) providing an agent which reacts with the surface. Additionally, the glassy polymer composition can be crosslinked before or after it is crazed to increase the mechanical strength of the membrane.

Abstract: The char-forming characteristics of vinyl aromatic polymers are improved by the incorporation therein of (1) active allyl and/or benzyl carbon moieties and (2) an arylsulfonate ester. In an example, a styrenic polymer comprising polyvinylbenzylacetate is given increased char-forming ability by the presence of pentaerythritol parabromobenzenesulfonate.

Abstract: A process for preparing N-halo .alpha.,.alpha.-disubstituted .beta.-lactams comprising reacting a 3-halo 2,2-bis(halomethyl) propionamide with a sufficient amount of an aqueous solution of a hypohalite to form the corresponding N-halo 3,3-bis-(halomethyl)-2-azetidinone.

Abstract: Flame retardant intumescent polyamides comprising repeating structural units of the formulas ##STR1## wherein X is independently chloro or bromo, and n and n' are each independently a positive integer are disclosed.

Abstract: Aqueous antimicrobial compositions which comprise a halogenated amide antimicrobial, such as 2,2-dibromonitrilopropionamide, a water miscible organic solvent such as a straight chain polyalkylene glycol (e.g., polyethylene glycol 200) or an ether thereof (e.g., a mono- or di-lower alkyl and/or phenyl ether) and water and which have improved stability are obtained by ensuring that such compositions are substantially free of glycols having a molecular weight of less than about 70 and of salts of organic acids. The resulting improved compositions exhibit reduced rates of decomposition of the halogenated amide antimicrobial relative to the corresponding aqueous compositions containing salts of organic acids and/or glycols having a molecular weight of less than about 70.

Abstract: Flame retardant intumescent polyamides comprising repeating structural units of the formulas ##STR1## wherein X is independently chloro or bromo, and n and n' are each independently a positive integer are disclosed.

Abstract: Aqueous antimicrobial compositions which comprise a halogenated amide antimicrobial, such as 2,2-dibromonitrilopropionamide, a water miscible organic solvent such as a straight chain polyalkylene glycol (e.g., polyethylene glycol 200) or an ether thereof (e.g., a mono- or di-lower alkyl and/or phenyl ether) and water are stabilized against decomposition of the halogenated amide antimicrobial by the addition of a carbamoyl or sulfamoyl stabilizer, such as dimethyl formamide, sulfamide, urea, oxamide, biuret, caprolactam, succinimide, etc. The compositions, so stabilized, exhibit reduced rates of decomposition of the halogenated amide antimicrobial relative to the corresponding non-stabilized aqueous compositions.

Abstract: Aqueous antimicrobial compositions which comprise a halogenated amide antimicrobial, such as 2,2-dibromonitrilopropionamide, a water miscible organic solvent such as a straight chain polyalkylene glycol (e.g., polyethylene glycol 200) or an ether thereof (e.g., a mono- or di- lower alkyl and/or phenyl ether) and water are stabilized against decomposition of the halogenated amide antimicrobial by the addition of an aldehyde stabilizer, such as formaldehyde, paraformaldehyde, N-formyl piperidine, vanillin, etc. The compositions so stabilized exhibit reduced rates of decomposition of the halogenated amide antimicrobial relative to the corresponding non-stabilized aqueous compositions.

Abstract: Novel esters of the formula: ##STR1## promote char formation in polymer compositions containing a monovinylidene aromatic monomer, such as styrene, and an ethylenically unsaturated carboxylic anhydride, such as maleic anhydride. In such esters, R is an n-valent tertiary hydrocarbyl radical, an n-valent tertiary chlorohydrocarbyl radical, an n-valent tertiary hydrocarbyl radical containing at least one chain linkage of oxygen or an inertly substituted n-valent tertiary hydrocarbyl radical containing at least one bromine atom.

Abstract: N-(5,7-Dibromo-1,3-benzoxathiol-2-ylidene)-N-methylmethanaminium bromide and the analogous diodo iodide, new compounds, are prepared by the thermal rearrangement of O-(2,4,6-tribromophenyl)-N,N-dimethylthiocarbamate and O-(2,4,6-triiodophenyl)-N,N-dimethylthiocarbamate. The first-named compound has antimicrobial utility. Both compounds are useful as starting materials for the preparation of bis-(3,5-dibromo-2-hydroxyphenyl)disulfide and 2,4-diiodo-6-mercaptophenol, respectively, by hydrolysis of the two first-named compounds with methanolic sodium hydroxide. Both the disulfide and the mercaptophenol compounds have antimicrobial utility.

Abstract: Esters of the formula: ##STR1## wherein R is an n-valent tertiary hydrocarbyl radical or an inertly substituted n-valent tertiary hydrocarbyl radical, promote char formation in polymer compositions containing a monovinylidene aromatic monomer, such as styrene, and an ethylenically unsaturated carboxylic anhydride, such as maleic anhydride.

Abstract: Halogenated .alpha.-methylbenzyl phenyl ethers have been found to be excellent fire retardants for thermoplastics such as polystyrene and polypropylene.