Abstract: A trilobal or quadrilobal fiber formed from thermoplastic polymers, said fiber having a cross-section comprised of a central core having three or four T-shaped lobes, the legs of each intersecting at the center of said core such that the angle between the legs of adjacent lobes is from about 80.degree. to about 130.degree..

Abstract: The present invention is directed to a copolymer of a fluoromonomer having the formula R.sub.1 R.sub.2 C=CR.sub.3 F wherein R.sub.1, R.sub.2 and R.sub.3 are selected from H and F, and R.sub.3 may be Cl when R.sub.1 and R.sub.2 are F; and a vinyl monomer having the formula H.sub.2 C=CHR.sub.x, wherein R.sub.x is a radical having the formula --O.sub.2 CR.sub.y, wherein R.sub.y is a radical selected from CH.sub.3 and C.sub.2 H.sub.5.The resulting copolymer comprises fluorinated units having the formula (R.sub.1 R.sub.2 C-CR.sub.3 F) wherein R.sub.1, R.sub.2 and R.sub.3 are selected from H and F, and R.sub.3 may be Cl when R.sub.1 and R.sub.2 are F, and corresponding amounts of vinyl units having the formula (H.sub.2 C-CHR.sub.x), wherein R.sub.x is selected from --CH.sub.3 and C.sub.2 H.sub.5. In an alternate and preferred embodiment the copolymer is hydrolyzed so that R.sub.x becomes --OH.

Abstract: This invention relates to medical devices formed totally or in part from homopolymers or copolymers comprising recurring carbonate moieties.

Abstract: Novel polycarbonate homopolymers and implantable bioresorbable medical devices fabricated therefrom.

Abstract: This invention relates to novel copolymers containing carbonate repeat units and ester repeat units.

Abstract: This invention relates to a fiber comprising a major amount of a continous phase comprising one or more melt processible polyesters of fiber forming molecular weight, and a minor amount of one or more polyolefins non-uniformly dispersed in said continuous phase such that the concentration of polyolefins at or near the surface of said fiber is greater than the concentration of polyesters at or near the surface of said fiber, and a process for preparing said fiber.

Abstract: This invention is directed to novel random copolymers and implantable devices fabricated therefrom.

Abstract: A method of forming foamed fibers which comprises the steps of forming a melt of a polymer of fiber-forming molecular weight in which is admixed a blowing agent, and a closed-cell-forming additive, extruding said melt through a spinnerette, quenching said melt downstream of said spinnerette under conditions at which bubbles form in said melt, and drawing said melt as it is quenched to produce a foamed fiber having fine bubbles contained therein is disclosed. The product fibers may contain substantially only closed-cells and/or substantially uniform cross sectional area cells.

Abstract: Polymer-bound alkyl diarylphosphinite catalyst compositions having the formula I: ##STR1## wherein the trivalent phosphorus is substituted by one alkoxy group and one aryl group and wherein the third bond of phosphorus is a P-C bond to a pendant aryl groups of the polymer matrix and wherein .circle.p --C.sub.6 H.sub.4 -- is a polymer matrix containing aromatic groups such as polystyrene cross-linked with divinylbenzene and wherein at least 1% of pendant aryl groups of the polymer matrix are bound to phosphorus and wherein Ar is substituted by electron-donating groups such as alkyl, alkoxy, and N,N-dialkylamino, are disclosed. Polymer-bound aryl dialkyl phosphonites having the formula II, .circle.p --C.sub.6 H.sub.4 --P(OR).sub.2 and polymer-bound diarylphosphinous chlorides having the formula .circle.p --C.sub.6 H.sub.4 --P--(Ar')--Cl are also disclosed. Processes for making the polymer-bound phosphinites, phosphonites and phosphinous chlorides are also disclosed.

Abstract: Selective conversion of acrylonitrile into 1,4-dicyano-1-butene by contacting a liquid phase comprising acrylonitrile with an effective amount of a polymer-bound alkyl diarylphosphinite catalyst having the formula I: ##STR1## wherein the trivalent phosphorus is substituted by one alkoxy group and one aryl group and wherein the third bond of phosphorus is a P--C bond to a pendant aryl group of the polymer matrix, such as polystyrene cross-linked with divinylbenzene is disclosed. Treatment of the liquid phase, prior to contacting same with the polymer-bound catalyst, with a drying agent comprising a polymer-bound dialkyl arylphosphonite and regeneration of the drying agent are also disclosed.

Abstract: A process for selective preparation of lactams which comprises contacting, in the vapor phase, an aliphatic or aromatic aminonitrile having the formula HR.sub.1 N--D--CN wherein D is a divalent organic moiety and wherein R.sub.1 is (C.sub.1 -C.sub.4) alkyl or hydrogen with an effective amount of a silica catalyst, in the form of substantially spherical beads having a BET surface area greater than about 250 m.sup.2 /g, preferably between 300 and 500 m.sup.2 /g, and an average pore diameter less than about 20 nanometers preferably 8-10 nanometers at a temperature in the range of about 200.degree. to about 400.degree. C. and at a hydrogen or inert gas flow with a pressure in the range of about 0 to about 300 kPa, in the presence of: (a) ammonia in an amount equal to from 0 to about 50 mole percent of the molar amount of aliphatic or aromatic aminonitrile present; and (b) water in an amount from at least about 1.

Abstract: Process for the selective conversion of dinitriles into the corresponding lactam by treating the dinitrile with an effective amount of a hydrogenation catalyst such as copper chromite in combination with a co-catalyst, such as titania, at a temperature in the range of from about 200.degree. C. to about 400.degree. C. and at a pressure of at least 50 kPa in the presence of water and hydrogen.

Abstract: A process for the oxidation of olefinically unsaturated substrates of the formula R--CH.dbd.CH-R' wherein R and R' are independently selected from members of the group consisting of H, alkyl, alkenyl, cycloalkyl, aryl and halo-, cyano- and ether-substituted alkyl, alkenyl, cycloalkyl and aryl which comprises reacting in the liquid phase said substrate with a rhodium nitro complex of the formula L.sub.n RhNO.sub.2, wherein n is 4 or 5 and wherein L.sub.n represents any combination of monodentate, bidentate, tridentate and tetradentate ligands such as to provide four or five bonding sites, for a time sufficient to produce an oxidized product of the formula RCH.sub.2 C(O)R' and a reduced product of the formula L.sub.n RhNO is disclosed. A preferred embodiment of the process wherein the rhodium nitro complex contains at least one ligand replaceable by olefin to be oxidized and operates to produce the oxidized product RCH.sub.2 C(O)R' in the absence of other Group VIII metals as co-catalyst is also disclosed.

Abstract: A dinitrile is hydrogenated to an omega-aminonitrile with hydrogen with a supported highly dispersed rhodium catalyst and only ammonia present. The catalyst is prepared by hydrolyzing a rhodium(III) halide or nitrate with strong aqueous base at elevated temperatures, drying the supported rhodium hydroxide at elevated temperatures and intimately contacting with hydrogen the dried product with hydrogen at 260.degree.-360.degree. C. High conversions, selectivity to aminonitrile and long catalyst service times and catalyst recyclability are achieved in the absence of an aprotic solvent.

Abstract: Polymer-bound alkyl diarylphosphinite catalyst compositions having the formula I: ##STR1## wherein the trivalent phosphorus is substituted by one alkoxy group and one aryl group and wherein the third bond of phosphorus is a P--C bond to a pendant aryl groups of the polymer matrix and wherein .circle.p --C.sub.6 H.sub.4 -- is a polymer matrix containing aromatic groups such as polystyrene cross-linked with divinylbenzene and wherein at least 1% of pendant aryl groups of the polymer matrix are bound to phosphorus and wherein Ar is substituted by electron-donating groups such as alkyl, alkoxy, and N,N-dialkylamino, are disclosed. Polymer-bound aryl dialkyl phosphonites having the formula II, .circle.p --C.sub.6 H.sub.4 --P(OR).sub.2 and polymer-bound diarylphosphinous chlorides having the formula .circle.p --C.sub.6 H.sub.4 --P--(Ar')--Cl are also disclosed. Processes for making the polymer-bound phosphinites, phosphonites and phosphinous chlorides are also disclosed.

Abstract: Selective conversion of acrylonitrile into 1,4-dicyano-1-butene by contacting a liquid phase comprising acrylonitrile with an effective amount of a polymer-bound alkyl diarylphosphinite catalyst having the formula I: ##STR1## wherein the trivalent phosphorus is substituted by one alkoxy group and one aryl group and wherein the third bond of phosphorus is a P--C bond to a pendant aryl group of the polymer matrix, such as polystyrene cross-linked with divinylbenzene is disclosed. Treatment of the liquid phase, prior to contacting same with the polymer-bound catalyst, with a drying agent comprising a polymer-bound dialkyl arylphosphonite and regeneration of the drying agent are also disclosed.

Abstract: A dinitrile is hydrogenated to an omega-aminonitrile with hydrogen in an aprotic solvent with a supported rhodium catalyst and ammonia present. The catalyst is prepared by hydrolyzing a rhodium (III) halide with strong aqueous base at elevated temperatures, drying the supported rhodium hydroxide at elevated temperatures and hydrogenating the dried product at elevated temperatures. High conversions, selectivity to aminonitrile and catalyst recyclability are achieved.

Abstract: A dinitrile is reacted with hydrogen in the presence of a solvent and a catalyst to form an omega-aminonitrile such as epsilon-aminocapronitrile at high selectivity. The catalyst is a rhodium complex of the formula (RR'Rh)A reacted with a strong base such as sodium hydroxide. R is derived from a diene such as 1,5-hexadiene. R' is a heterocyclic containing an aromatic ring nitrogen. A is a complex monovalent anion such as hexafluorophosphate.

Abstract: An olefinically unsaturated substrate is reacted with a transition metal nitro complex, having the transition metal bonded to the nitrogen of the nitro radical, in the presence of a thallium(III) compound as cocatalyst to cause the production of oxirane products, rather than aldehydes or ketones. The process is applicable to the production of ethylene oxide, propylene oxide, epichlorohydrin, epoxidized fatty acids and oxiranes from various other internal and terminal olefins.

Abstract: Hydrogen peroxide production by oxidation of a 2-alkyl-9,10-dihydroxyanthracene, especially the 2-(t-butyl) compound, and catalytic hydrogenation of the resulting 2-alkylanthraquinone back to the dihydroxy compound, using a water-insoluble (bipyridyl) rhodium complex as hydrogenation catalyst. Especially such process carried continuously in a cell in which an organic phase is separated by a porous membrane from an aqueous phase, and the anthraquinone is hydrogenated on the organic side of the cell and hydrogen peroxide is obtained from the aqueous phase. Preferably the rhodium complex is formed with a bipyridyl ligand attached to polystyrene beads, whereby to assure that rhodium is not carried into the hydrogen peroxide production side of the cell.