A prepreg having a high processability and laminating performance in an automated lay-up device and serving to produce a cured product having good physical properties is described, and also a method for the production thereof, the prepreg comprising at least the components [A] to [E] listed blow and having a structure incorporating a first layer composed mainly of the component [A] and a first epoxy resin composition that contains the components [B] to [D] but is substantially free of the component [E] and a second layer composed mainly of a second epoxy resin composition that contains the components [B] to [E] and disposed adjacent to each surface of the first layer: [A] carbon fiber, [B] epoxy resin, [C] curing agent, [D] thermoplastic resin, and [E] particles containing a thermoplastic resin as primary component and having a volume-average particle diameter of 5 to 50 μm.

Provided is a prepreg including the following constituents [A] to [C], the prepreg satisfying the following conditions [I] to [III]: [A]: a sizing agent-coated carbon fiber; [B]: an epoxy resin having a specific structure; and [C]: a hardener for [B], [I]: an epoxy resin composition including the constituents [B] and [C] has a nematic-isotropic phase transition temperature in a temperature range of 130° C. to 180° C.; [II] a prepreg after isothermal holding at 100° C. for 30 minutes does not have a high-order structure originated from a diffraction angle of 2θ=1.0° to 6.0° measured by wide angle X-ray diffraction at 100° C.; and [III]: a prepreg after isothermal holding at 180° C. for 2 hours has a high-order structure originated from the diffraction angle of 2θ=1.0° to 6.0° measured by wide angle X-ray diffraction at 180° C.

Pre-impregnated composite material (prepreg) that can be cured/molded to form aerospace composite parts. The prepreg includes carbon reinforcing fibers and an uncured resin matrix. The resin matrix includes an epoxy resin component, polyethersulfone as a toughening agent, a thermoplastic particle component, a nanoparticle component and a curing agent.

A prepreg is described having good handleability and a low resin flow, facilitating the work in the process of a molded body and improving the dimensional accuracy of the molded body, where the prepreg includes a fiber substrate; and a resin layer containing a thermosetting resin composition containing at least components [A] and [B] below, stacked on one surface of the fiber substrate, wherein the fiber substrate is impregnated with a part of the thermosetting resin composition of the resin layer, the thermosetting resin composition having a complex viscosity 3*24 at 24 C. of 20,000 to 100,000 Pa.Math.s and a complex viscosity 3*70 at 70 C. of 100 to 5,000 Pa.Math.s, and a volatile amount of the thermosetting resin composition is 1 mass % or less when a total mass of the prepreg is 100 mass %.

[A] Thermosetting resin

[B] Curing agent of [A]

Composite honeycomb that may be contoured to form composite honeycomb structures, which have tight radii of curvatures and/or compound curvatures, and which are suitable for use in high temperature environments. The method for making the composite honeycomb involves using high temperature prepreg to make a flexible composite honeycomb that is formed into a composite honeycomb precursor. A high temperature coating resin is applied to the composite honeycomb precursor to form the high temperature composite honeycomb.

A polyester film and a method for producing the same are provided. The polyester film includes a heat resistant layer. The heat resistant layer includes a high temperature resistant resin material and a polyester resin material. The high temperature resistant resin material and the polyester resin material are melted and kneaded with each other via a twin screw granulator. The twin-screw granulator has a twin-screw temperature between 250 C. and 320 C., and the twin-screw granulator has a twin-screw rotation speed between 300 rpm and 800 rpm, so that the high temperature resistant resin material is dispersed in the polyester resin material with a particle size of between 50 nm and 200 nm.

A low cost, high selectivity asymmetric polyimide/polyethersulfone (PES) blend hollow fiber membrane, a method of making the membrane and its use for a variety of liquid, gas, and vapor separations such as deep desulfurization of gasoline and diesel fuels, ethanol/water separations, pervaporation dehydration of aqueous/organic mixtures, CO.sub.2/CH.sub.4, CO.sub.2/N.sub.2, H.sub.2/CH.sub.4, He/CH.sub.4, O.sub.2/N.sub.2, H.sub.2S/CH.sub.4, olefin/paraffin, iso/normal paraffins separations, and other light gas mixture separations. The polyimide/PES blend hollow fiber membrane is fabricated from a blend of a polyimide polymer and PES and showed surprisingly unique gas separation property with higher selectivities than either the polyimide hollow fiber membrane without PES polymer or the PES hollow fiber membrane without PES polymer for gas separations such as for H.sub.2/CH.sub.4, He/CH.sub.4, H.sub.2S/CH.sub.4, CO.sub.2/CH.sub.4 separations.

A tape prepreg formed by impregnating, with resin, a reinforcing fiber bundle in which reinforcing fibers are aligned in one direction, in which a cross-section of the tape prepreg bundle perpendicular to an orientation direction has a portion in which a thickness continuously increases from one end portion and the other end portion in a width direction toward the center in the width direction, and all angles formed by any one boundary line in a thickness direction of the perpendicular cross-section and a boundary line in the width direction are acute angles.

Composite honeycomb that may be contoured to form composite honeycomb structures, which have tight radii of curvatures and/or compound curvatures, and which are suitable for use in high temperature environments. The method for making the composite honeycomb involves using high temperature prepreg to make a flexible composite honeycomb that is formed into a composite honeycomb precursor. A high temperature coating resin is applied to the composite honeycomb precursor to form the high temperature composite honeycomb.

A porous membrane includes a polymer which includes one or more structural units selected from the group consisting of a structural unit represented by Formula (I) and a structural unit represented by Formula (II), in which a content of the structural unit represented by Formula (II) is 1% by mass or more and less than 10% by mass with respect to a total mass of the structural unit represented by Formula (I) and the structural unit represented by Formula (II)

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