Abstract: Thermoformable, thermosettable resins essentially free of secondary alcohol groups are obtained by reaction of oxiranes in active hydrogen-free polyepoxide with carboxylate and/or carbonate groups in active hydrogen-free aryl polyesters, polycarbonates or copolyestercarbonates in the presence of catalytically effective amounts of certain polyorgano phosphonium or phosphine iminium salts.

Abstract: Foraminous plates formed from coiled or parallel tape lengths may be inserted between the tubesheet and a ported casing-end in a hollow-fiber type permeator, to convey effluent from the fiber lumens to the port and to support the tubesheet against the pressure differential between its inner and outer faces. The face of the support plate which the tubesheet will bear against is defined by edges of the tapes, which are held radially or laterally apart by spacing means adapted to permit effluent flow through the plate between the tapes. Either the casing-end or the plate surface bearing against it is grooved.

Abstract: Elongated, large diameter, helically wound, hollow fiber bundles which are stable, do not require "dead-end tubesheets" to keep the bundle ends from slipping and exhibit only slight "dog-boning" can be formed by controlling the winding parameters so that the bundle consists of successively shorter or longer "formations" of successively longer strata, each stratum consisting of from about one to a plurality of coverages (of the underlying core or bundle surface).

Abstract: Vinyl ester/styrene mixtures are flexibilized by addition thereto of minor amounts of urethanes which (1) comprise at least one polyglycol moiety and two urethane groups and are terminated by vinyl-reactive end groups, and (2) form a dispersed second phase in the cured mixture. The flexibilized compositions otherwise largely retain the characteristic properties of the unflexibilized mixtures.

Abstract: Elongated, large diameter, helically wound, hollow fiber bundles which are stable, do not require "dead-end tubesheets" to keep the bundle ends from slipping and exhibit only slight "dog-boning" can be formed by controlling the winding parameters so that the bundle consists of successively shorter or longer "formations" of successively longer strata, each stratum consisting of from about one to a plurality of coverages (of the underlying core or bundle surface).

Abstract: Liquid epoxy resins can be converted to non-sintering, relatively low equivalent weight, flakable solid opoxides having relatively low melt viscosities by advancing the resins with 1,1,1-tri(hydroxyphenyl)alkanes or -alkenes in which the alkane or alkene moiety contains from 1 to 11 carbons.

Abstract: The selective reduction of pentachloropyridine to 2,3,5,6-tetrachloropyridine is achieved by contacting the pentachloropyridine as a solution in perchloroethylene or methylene chloride with zinc dust in a basic aqueous medium.

Abstract: Polycycloalkenyl-terminated, unsaturated polyesters or polyesteramide compositions, including or not including non-resinous vinyl monomers, are flexibilized by incorporation in the uncured composition of vinyl-terminated urethane oligomers comprising at least one polyglycol unit.

Abstract: Liquid epoxy resins can be converted to non-sintering, relatively low equivalent weight, flakable solid epoxides having relatively low melt viscosities by advancing the resins with 1,1,1-tri(hydroxyphenyl)alkanes or -alkenes in which the alkane or alkene moiety contains from 1 to 11 carbons.

Abstract: The adducts of isocyanates wtih benzoxazolones or benzoxazinediones are novel compounds which may be employed as blocked isocyanates and are particularly useful as latent, epoxide curing agents. At typical epoxide curing temperatures, the isocyanate is oxirane or hydroxyl reactive and the benzoxazole or benzoxazinedione acts like a di- or trifunctional phenol, respectively.

Abstract: Several advantages as to ease of cell fabrication, maximum cell size, fiber breakage, tubesheet tightness, resistance to tubesheet deformation in prolonged service, safety, etc., can be realized by using as the tubesheet in a hollow fiber type battery cell one which is elongated in shape, has a substantially smaller diameter than the fiber "bundle" depending from it and in which the fiber ends passing through it are closely packed.

Abstract: Powders consisting essentially of zinc but having lead contents of from about 1000 to about 30,000 ppm can readily be produced by electrolysis of lead-containing, zinc halide solutions and are superior reductants for the preparation of symmetrical tetrachloropyridine from pentachloropyridine.

Abstract: Epoxy resins reacted with an oxirane group containing phosphonate of the formula: ##STR1## wherein R is hydrogen or lower alkyl and R.sub.1 is lower alkyl are described. The backbone of the epoxy resin contains a functional substituent which reacts with (I) preferably a hydroxyl substituent. The cured epoxy resins reacted with the phosphonate (I) have improved flame resistance or glass temperatures.

Abstract: Advanced epoxides which develop desirable resin properties and processing characteristics at considerably lower degrees of advancement than conventional advancement products are obtainable by employing a benzoxazolone or a hydroxy benzimidazole as the advancing agent.

Abstract: 2-(3H)-benzoxazolone and certain other benzo-N-heterocycles, as such or as their adduction products with epoxides, may be employed as organo-soluble, latent phenolic curing agents for epoxy resins. The phenolic hydroxyls are provided by rearrangement of the adduction products. Excellent shelf lives, pot lives, gel times and physical properties result.

Abstract: The walls of bores made in tubesheet/hollow fiber composite structures are trimmed, and the bores may be enlarged, by use of a rotating, generally tubular tool comprising a cutting head with outwardly extending portions of lands terminating in teeth having cutting edges generally parallel to the central axis of the tool. The lands are separated by ports in the tool wall which communicate with the hollow interior of the tool. The trimmings formed are deflected by the teeth into a flow of sweep gas passing through the interior of the tool. The operation is facilitated by flash-freezing of any portions of the generally softer fibers exposed and protruding into the bore or across the mouths of the fiber lumens.

Abstract: Polyphase, transparent, polyblock, oligomer-free, segmented urethane polymers having molecular weights of from about 100,000 to about 200,000 and being eminently suited for use in medical devices such as blood bags, etc., are deriveable from chain extenders, free diisocyanate molecules and prepolymers consisting essentially of linear molecules which are terminated at each end by isocyanate groups. The prepolymer molecules consist of n branched, polyether glycol residues joined through intervening carbamate groups with (n+1) diisocyanate residues, n ranging from about 1 to 4 and having an average value of less than 2. The polyether glycols have molecular weights of from about 1000 to about 6000 and are methylol-terminated chains of C.sub.3 -C.sub.6 alkylene oxide units. Importantly, the final polymers are free of domain crystallinity.

Abstract: Several advantages as to ease of cell fabrication, maximum cell size, fiber breakage, tubesheet tightness, resistance to tubesheet deformation in prolonged service, safety, etc., can be realized by using as the tubesheet in a hollow fiber type battery cell one which is elongated in shape, has a substantially smaller diameter than the fiber "bundle" depending from it and in which the fiber ends passing through it are closely packed.

Abstract: 2,3,5,6-Tetrachloropyridine is obtained in high selectivity and yield by the electrocatalytic reduction at a stainless steel cathode of pentachloropyridine in an aqueous acetonitrile solution containing zinc chloride. Chlorine or oxygen may be co-produced at the anode.

Abstract: Foraminous plates formed from coiled or parallel tape lengths may be inserted between the tubesheet and a ported casing-end in a hollow-fiber type permeator, to convey effluent from the fiber lumens to the port and to support the tubesheet against the pressure differential between its inner and outer faces. The face of the support plate which the tubesheet will bear against is defined by edges of the tapes, which are held radially or laterally apart by spacing means adapted to permit effluent flow through the plate between the tapes. Either the casing-end or the plate surface bearing against it is grooved.