Abstract: An improved process for controlling and reducing the concentration of free carboxyl end groups in condensation polyester melt spun fiber is provided. The difunctional compound, serves to increase the intrinsic viscosity of the fiber. The process comprises admixing and reacting with molten polyester polymer an effective amount of a lactim compound of the formula ##STR1## wherein x and y may be alike or different and represent an integer of 2 to 15; andR.sub.1 and R.sub.2 are independently hydrogen, halogen, nitro, amine, C.sub.1 -C.sub.10 alkyl, C.sub.5 -C.sub.12 cycloalkyl, C.sub.7 -C.sub.9 alkyl aromatic, or C.sub.6 -C.sub.10 aromatic.The lactim reacted polymer is then melt spun to form a fiber.

Abstract: A high tenacity fiber for reinforcing plastic composites, the fiber being selected from the group consisting of polyester, aliphatic polyamide, and combinations thereof. The fiber is treated with a composition comprising an aqueous solution of carboxyl-terminated, oil-free alkyd resins based on an aliphatic glycol or glycols or a glycol ether or ethers containing 2 to 12 carbon or carbon plus ether oxygens with a combination of aromatic di- or trifunctional carboxylic acids, said resins having a degree of esterification below the gel point of the resins to enhance stiffness of the fiber for cutting.

Abstract: A high tenacity fiber for reinforcing plastic composites, the fiber being selected from the group consisting of polyester, aliphatic polyamide, and combinations thereof. The fiber is treated with a composition comprising an aqueous solution of carboxyl-terminated, oil-free alkyd resins based on an aliphatic glycol or glycols or a glycol ether or ethers containing 2 to 12 carbon or carbon plus ether oxygens with a combination of aromatic di- or trifunctional carboxylic acids, said resins having a degree of esterification below the gel point of the resins to enhance stiffness of the fiber for cutting.

Abstract: A high tenacity fiber for reinforcing plastic composites, the fiber being selected from the group consisting of polyester, aliphatic polyamide, and combinations thereof. The fiber is treated with a composition consisting essentially of an organofunctional silane in an amount sufficient to achieve 0.02 to 1.0 weight percent of the silane on the fiber, and a diluent which provides for the hydrolysis of the silane to a silanol. The fiber is used to reinforce a plastic composite additionally comprising a resin matrix.

Abstract: An improved process for controlling and reducing the concentration of free carboxyl end groups in condensation polyester melt spun fiber is provided. By selection of a multifunctional compound, it is possible to increase the intrinsic viscosity of the fiber. The process comprises admixing and reacting with molten polyester polymer an effective amount of a lactim compound of the formula ##STR1## wherein n is an integer of 2 to 15;m is an integer of 1 to 4;R.sub.1 and R.sub.2 are independently hydrogen, halogen, nitro, amine, C.sub.1 -C.sub.10 alkyl, C.sub.5 -C.sub.12 cycloalkyl, C.sub.7 -C.sub.9 alkyl aromatic, or C.sub.6 -C.sub.10 aromatic; andR.sub.3 is a mono- to tetravalent organic radical selected from the group consisting of C.sub.1 -C.sub.32 alkyl, C.sub.5 -C.sub.14 cycloalkyl, C.sub.7 -C.sub.16 alkyl aromatic, and C.sub.6 -C.sub.14 aromatic.The lactim reacted polymer is then melt spun to form a fiber.

Abstract: A high tenacity fiber for reinforcing plastic composites, the fiber being selected from the group consisting of polyester, aliphatic polyamide, and combinations thereof. The fiber is treated with a composition consisting essentially of an organofunctional silane in an amount sufficient to achieve 0.02 to 1.0 weight percent of the silane on the fiber, and a diluent which provides for the hydrolysis of the silane to a silanol. The fiber is used to reinforce a plastic composite additionally comprising a resin matrix.

Abstract: A high tenacity fiber for reinforcing plastic composites, the fiber being selected from the group consisting of polyester, aliphatic polyamide, and combinations thereof. The fiber is treated with a composition comprising a vinyl chloride copolymer having a glass transition temperature of greater than about 60.degree. C., to enhance compatibility of the fiber and a resin matrix reinforced therewith. A process is provided to enhance fiber stiffness for cutting and comprises treating the fiber with the referenced composition, followed by heating the treated fiber to a temperature above the glass transition temperature to cause the copolymer to flow and form a film which substantially coats the fiber.

Abstract: A fiber finish composition, a process for treating polyester yarn therewith and polyester yarn so treated are all disclosed. The fiber finish composition, which is preferably applied as an overfinish to the yarn subsequent to drawing of the yarn, comprises about 60 to 90 weight percent of water; about 0.3 to 10 weight percent of gamma-glycidoxypropyltrimethoxysilane; about 0.05 to 4.0 weight percent of a catalyst selected from the group consisting of urea and a solution of a cobalt, stannous, iron, nickel, zinc, manganese or chromium salt of 2-ethylhexoic acid or lauric acid in a carrier which is miscible in water; and about 6.5 to 38.6 weight percent of a compatible noncontinuous phase. The catalyst, alternatively, may form 0.00025 to 0.

Abstract: A process for the production of reinforced rubber articles formed from polyester yarn embedded into rubber stock is disclosed. The process comprises the steps of: (1) treating the yarn with a finish composition which comprises water and a silane having the structural formula: ##STR1## wherein n=2 to 5, and (2) including from about 2 to 50 parts, per hundred parts of rubber, of silica particles in the rubber stock. The reinforced rubber article is preferably a pneumatic passenger tire which has excellent adhesion of tire cord to rubber.

Abstract: High molecular weight linear condensation polyesters are stabilized against deterioration by heat by reacting the polyester in molten form with alkylene carbonates in the presence of a catalytic amount of a compound selected from the group consisting of sodium thiocyanate and potassium thiocyanate.

Abstract: High molecular weight linear condensation polyesters are stabilized against deterioration by heat by reacting the polyester in molten form with alkylene carbonates in the presence of a catalytic amount of a compound selected from the group consisting of sodium iodide and potassium iodide.

Abstract: High molecular weight linear condensation polyesters are stabilized against deterioration by heat with a stabilizer comprising 2-(phenoxy methyl)-3-phenyl oxirane.

Abstract: The improvement of passing an inert, preferably vaporizable and condensible, liquid material through or over a polyester molten mass in a polymer reactor to further increase surface area-to-volume ratio and/or lower the partial pressure of vaporous products of condensation so that viscosity of the polymer is increased at a substantially greater rate in the same residence time is taught for the prior art condensation process in a film-forming reactor at temperatures of 275.degree. C. to 300.degree. C., pressures of 0.1 to 760 Torr, and residence times of 0.1 to 6 hours. A polymer having an intrinsic viscosity above 0.65, preferably over 0.7, is produced.

Abstract: Using an alkanolamine titanium chelate catalyst, such as triethanolamine titanium chelate, in small catalytic amounts to esterify and polycondense aromatic polycarboxylic acids or anhydrides, such as terephthalic acid, with a glycol, such as ethylene glycol at low glycol to acid reactant ratios surprisingly yields a polyester of low diethylene glycol content without adding an additional diethylene glycol suppressant.

Abstract: High molecular weight linear condensation polyesters are stabilized against deterioration by heat by reacting the polyester in molten form with certain polycarbonates in the presence of a catalytic amount of a phosphonium compound selected from the group consisting of tetra-n-alkylphosphonium acetates and tetra-n-alkylphosphonium halides. For the purpose of this disclosure, polycarbonates are defined as linear polyesters of carbonic acid in which the carbonate groups recur in the polymer chain. In continuous production of the improved polyesters, it is preferred that the polycarbonate and catalyst be added to the process stream with mixing at a point to give 2 to 15 minutes reaction time under superatmospheric pressure before the polyester enters the last polycondensation reactor.

Abstract: High molecular weight linear condensation polyesters are stabilized against deterioration by heat by reacting the polyester in molten form with an epoxy compound having 5 to 25 carbon atoms in the molecule and selected from the group consisting of ##STR1## where R represents the radical remaining after removal of the carboxyl group from a monocarboxylic acid, R.sub.1, R.sub.2, R.sub.3 and R.sub.4 represent hydrogen or hydrocarbon radicals, and n is an integer that can be 0 to 3.

Abstract: High molecular weight linear condensation polyesters are stabilized against deterioration by heat with a stabilizer comprising an N-epoxyalkyl imide of a dicarboxylic acid, having 5 to 20 carbon atoms in the imide molecule and composed of carbon, hydrogen, carbonyl and epoxy oxygen, and imide nitrogen atoms, said epoxy oxygen being linked to adjacent carbon atoms.

Abstract: High molecular weight linear condensation polyesters are stabilized against deterioration by heat by reacting the polyester in molten form with an epoxy compound having 5 to 25 carbon atoms in the molecule and selected from the group consisting of ##STR1## where R represents the radical remaining after removal of the carboxyl group from a monocarboxylic acid, R.sub.1, R.sub.2, R.sub.3 and R.sub.4 represent hydrogen or hydrocarbon radicals, and n is an integer that can be 0 to 3.