Abstract: In a continuous process for the manufacture of aromatic polyesters by polycondensation of mono- or multi-nuclear substituted or unsubstituted diphenols, with halides of aromatic dicarboxylic acids according to the two-phase interface polycondensation process, the first step is to produce continuously a fine pre-emulsion with an organic solvent and from the aqueous phase, consisting of a solution obtained from the diphenols, of an alkaline hydroxide in order to form the diphenates and possibly of a phase transfer catalyst in water or in a mixture of water and of an organic solubilizer. This pre-emulsion is fed in quantities to a dispersion unit jointly with the organo-liquid phase forming the acid chloride solution.

Abstract: Polyimides having a high thermal and oxidative stability are prepared by reacting a mixture of monomers comprising (a) a dialkyl, trialkyl, or tetraalkylester of an aromatic tetracarboxylic acid, (b) an aromatic diamine, and (c) an end cap compound. The ratio of (a), (b), and (c) is chosen so that upon heating the mixtures, low molecular weight prepolymers are formed, the prepolymers having only one end cap radical and being suitable for chain extension and crosslinking to form high molecular weight, thermally stable polyimides. Upon heating, the prepolymers form polyimide resins, which can have T.sub.g in excess of 600.degree. F. and superior physical properties.

Abstract: A novel class of sulfonamoyl-substituted 1,6-diaza[4.4]spirodilactams, having a sulfonamoyl substituent on the hydrocarbyl group attached to each spiro ring nitrogen atom, is useful for the preparation of polymers, including polyamides and as latent curing agents for epoxy resins.

Abstract: Polyimides having a high thermal and oxidative stability are prepared by reacting a mixture of monomers comprising (a) a dialkyl, trialkyl, or tetraalkylester of an aromatic tetracarboxylic acid, (b) an aromatic diamine, and (c) an end cap compound. The ratio of (a), (b), and (c) is chosen so that upon heating the mixtures, low molecular weight prepolymers are formed, the prepolymers having only one end cap radical and being suitable for chain extension and crosslinking to form high molecular weight, thermally stable polyimides. Upon heating, the prepolymers form polyimide resins, which can have T.sub.g in excess of 600.degree. F. and superior physical properties.

Abstract: This invention pertains to novel copolyesters consisting essentially of units (I), (II), (III), and (IV). ##STR1## and blends of these polymers and articles made from both. Units (I), (II), (III), and (IV) are present in specified proportions as defined in the "Description of the Invention".The instant copolyesters display orientation in the molten state, good fiber ratings and high strength. Advantageously, the polymers of the present invention display a significant improvement in viscosity and moldability of the neat polymer. The polymers have excellent mechanical and surface properties including blister resistance, strength, toughness, and ability to vapor phase solder, and form strong fibers while still maintaining a high heat distortion temperature. They have melting points in the range of from about 250.degree. to about 360.degree. C. and are melt-processible. Advantageously, these compositions filled with about 30 weight percent of glass fibers display heat distortion temperatures of up to 240.degree.

Abstract: A process for preparing a polyarylene sulfide which comprises reacting an alkali metal sulfide compound and a polyhalo-substituted aromatic compound in an organic polar solvent in the presence of(A) an alkali metal salt of a phenolic aromatic carboxylic acid of the formula:(HO).sub.m --Ar--(COOM).sub.nwherein Ar is a di- to tetravalent aromatic group having 6 to 24 carbon atoms; M is an alkali metal; and m and n are each 1 or 2,(B) an alkali metal hydroxide and/or an alkali metal alcoholate, and optionally,(C) an alkali metal salt of an inorganic acid.

Abstract: There are disclosed methods and compositions for retarding the room temperature gelation and eventual hardening of phenolic resole resins when such resins are mixed with lightburned magnesium oxide or magnesium hydroxide hardening agents with or without an ester functional hardening agent. Retardation of gelation and hardening is achieved by incorporating into said mixture a compound which decreases the solubility of magnesium in said mixture. Additionally, hardening at higher temperatures, thermal curing, as well as refractories, coated abrasives, polymer concrete, and other methods and compositions of this invention are disclosed.

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

Abstract: Disclosed herein is an aromatic amine resin formed of a mixture of aromatic amine compounds represented by the following general formula (a): ##STR1## wherein A means a phenylene, alkyl-substituted phenylene, diphenylene, diphenyl ether or naphthylenyl group, R.sup.1 denotes a halogen atom or a hydroxyl, C.sub.1-4 alkoxy or C.sub.1-5 alkyl group, l stands for 1 or 2, m is an integer of 0-3, when m is 2 or 3, R.sup.1 s may be the same or different and two of R.sup.1 s may join together into a 5- to 6-membered alicyclic moiety which may optionally contain one or more side chains, and n stands for an integer of 0-300.

Abstract: An aromatic polyester comprising the repeating units (A), (B), (C) and (D) represented by the following formulae in amounts of 0 to 80 mole %, 10 to 50 mole %, 5 to 50 mole % and 0 to 30 mole %, respectively, having a logarithmic viscosity of 1.0 dl/g or more and capable of being melt-molded at a temperature of 350.degree. C. or less: ##STR1## where R represents a C.sub.2 -C.sub.6 alkylene, and--O--AR--O-- (D)where Ar represents a divalent aromatic residue, and a process for producing the same. The aromatic polyesters according to the present invention combine moldability and heat resistance in a good state and have mechanical properties of sufficient practical value. An aromatic polyester according to the present invention shows optical anisotropy at a molten state.

Abstract: Novel thermosetting resin compositions are disclosed which comprise a 2,7-dioxo-1,6-dioxaspiro[4.4]nona-3,8-diene compound and at least one other reactive, polymerizable monomer which has at least two functional group substituents which contain active hydrogen atoms or multiple bonds between adjacent atoms. The thermosetting resins, upon application of heat, give crosslinked, cured products having good properties.

Abstract: Polybenzazole polymers are conveniently synthesized in the presence of a reducing agent, such as tin (II) chloride.

Abstract: Novel thermotropic polyesters and polyester-amides containing fluorine bearing linking groups are disclosed and claimed. Preferred embodiments include thermotropic polymers prepared from 4-Hydroxybenzoic acid, 6-hydroxy-2 naphthoic acid, 2,2-bis(4-carboxyphenyl)hexafluoropropane, hydroquinone, and terephthalic acid.

Abstract: A two-step process to make a poly(arylene sulfide sulfone) polymer containing ether groups having high molecular weights is described. In the first step an aromatic diphenol, a dihaloaromatic sulfone, a polar organic compound and an alkali metal base are reacted at an elevated temperature. During the first step the reactor is vented. Subsequently, a sulfur source is added to form a poly(arylene sulfide sulfone) polymer containing ether groups. An alkali metal carboxylate is also present in the second step. The polymers prepared by the invention method exhibit higher inherent viscosities, indicating higher molecular weight.

Abstract: Novel polyimide and polyisoimide oligomers and precursors thereof, end-capped with diaryl substituted acetylene.These novel end-capped polyimide or polyisoimides oligomers are useful for composites, molding compounds, adhesives, and electronic applications.

Abstract: The invention relates to linear and branched poly-p-arylene sulfides (PAS), preferably poly-p-phenylene sulfides (PPS), which have an extremely low proportion of defect or foreign structures, to a process for their production and to their use for the production of molded articles.

Abstract: The invention is a method of producing a polyester filament which has a superior combination of tensile, dyeability and shrinkage properties. The method comprises forming a polyester copolymer from a mixture consisting essentially of terephthalic acid (TA) or dimethyl terephthalate (DMT), ethylene glycol, adipic acid, and pentaerythritol wherein the adipic acid is added in an amount of between 1.3 and 3.2 weight percent of the terephthalic acid and pentaerythritol is added in the amount from 175 to 700 ppm by weight of terephthatlic acid; forming the filament from the copolymer, drawing the copolymer filament, and heat-setting the drawn filament. The invention also comprises the enhanced fiber formed by the process having an atmospheric dyeability greater than that of an unenhanced PET produced under identical conditions except for the addition of the adipic acid and pentaerythritol, a modulus of greater than 3.0 g/denier, a tenacity from about 5 to 7 g/denier and a hot air shrinkage of less than 10%.

Abstract: Macrocyclic polyarylate oligomers containing a mixture of isophthalate and terephthalate moieties are prepared by reaction of a mixture of isophthaloyl and terephthaloyl chloride with one or more bisphenols under specific reaction conditions. They are characterized by a reduced degree of crystallinity and therefore lower processing temperatures than the corresponding isophthalate oligomers.

Abstract: Low-melting polymers containing at least one Z-configured stilbene group are produced by reaction of Z-configured bifunctional stilbene compounds with bifunctional monomers, oligomers or relatively high molecular weight components at temperatures in the range from -30.degree. to 250.degree. C., optionally in the presence of organic solvents and/or diluents and/or catalysts, the Z-configuration of the stilbene units remaining intact. The low-melting polymers may be processed by standard methods to moldings of various kinds which may be converted by treatment of temperatures of 250.degree. to 500.degree. C. and/or by irradiation at wavelengths of 200 to 800 nm into high-melting plastics articles of high heat resistance.

Abstract: Polyimides having a high thermal and oxidative stability are prepared by reacting a mixture of monomers comprising (a) a dialkyl, trialkyl, or teThis invention was made with Government support under F33615-88-C-5409 awarded by the Department of the Air force. The Government has certain rights in this invention.