A method for preparing a thermoplastic polyurethane film having a large thickness and excellent durability, and a thermoplastic polyurethane film prepared thereby are provided.

A method for bonding composite substrates includes coupling a first co-cure prepreg layer having a first off-set amine to epoxide molar ratio onto a surface of a first composite substrate and coupling a second co-cure prepreg layer having a second off-set amine to epoxide molar ratio onto a surface of a second composite substrate. The first and second composite substrates are cured to the first and second co-cure prepreg layers, respectively, using a first cure cycle (including B-stage and cure temperatures) to form a first and a second co-cure prepreg layer portion. The method further includes coupling the first co-cure prepreg layer portion to the second co-cure prepreg layer portion and applying a second cure cycle to cure the first co-cure prepreg layer portion of the first composite substrate to the second co-cure prepreg layer portion of the second composite substrate to form a monolithic covalently bonded composite structure.

A method for joining structural elements to a component made of at least one fiber-reinforced plastics material, includes providing at least two structural elements made of at least one fiber-reinforced plastics material having a particular matrix; providing at least one film element made of a thermoplastic heavy-duty material; arranging the at least one film element on a surface of one of the structural elements or between surfaces to be joined of the at least two structural elements to be joined; and producing the component to be joined in a curing process.

A mat unit is formed from at least two layers ultrasonically welded together. Each layer is individually formed from non-vinyl nontoxic thermoplastic elastomer (TPE) material. In ultrasonically joining the two layers together, there is no need to use additional materials, such as adhesive (i.e., chemical attachment) or stitched thread (i.e., mechanical attachment) to form the joint/weld point. Once formed from the two layers, the mat unit has four quadrants and a plurality of longitudinal ribs integrally formed in the first layer positioned in the first and third quadrants, and a plurality of transverse ribs integrally formed in the first layer positioned in the second and fourth quadrants. Additionally, there are a plurality of longitudinal ribs integrally formed in the second layer positioned in the second and fourth quadrants, and a plurality of transverse ribs integrally formed in the second layer positioned in the first and third quadrants.

Aspects of the disclosure relate to manufacturing a balloon envelope for use in a stratospheric balloon system. For instance, a stream of polyethylene mixture us extruded. through an extruder in order to orient molecules of polymer chains of polyethylene and to provide an oriented film. The oriented film is passed through an electron beam and thereby crosslinking the polymer chains to provide a cross-linked film. The cross-linked film is heat sealed to form the balloon envelope

The manufacture of structural elements for aircraft requires the use of complex and costly methods, particularly in the case of parts of elongate overall shape and variable thickness or cross section made of composite material. The disclosure herein proposes to overcome this problem by a method that allows the manufacture of a structural part from a preform made of composite material of simple shape obtained by pultrusion and of one or more reinforcing elements made of composite material and secured by cocuring with the preform to a region of this preform which region is to be reinforced.

A part made of a fiber-reinforced composite material includes a structure made from a set of fibers supported in a thermosetting resin and a peel ply across all or part of the outer surface of the structure. The part has a gradient of polymerization at the interface between the structure and the peel ply. Also, methods for making such a part and methods for bonding such parts.

A method for manufacturing a vane from a composite material with a fitted metal leading edge includes the successive draping, on a template of the leading edge of the vane to be manufactured, of a first layer of a base material and of a second layer of an adhesive material, the transfer of the first and second draped layers in the recess of a metal foil, the positioning of the foil including the first and second draped layers alongside the leading edge of a vane preform including a fiber reinforcement impregnated with a precursor of a matrix, the co-curing of the vane preform and of the first and second draped layers so as to obtain a vane made of composite material including on its leading edge a bonded metal foil.

A method for producing a component from two or more sub-components includes the steps of: producing each of the sub-components using an additive manufacturing process in which a resin, which is radiant-energy-curable, is partially cured using a selective application of radiant energy, wherein each sub-component includes a joint surface in which the resin is partially cured which is cured to a lesser degree than the remainder of the respective sub-component, so as to leave the joint surfaces in a condition suitable for bonding; assembling the sub-components with their respective joint surfaces in mutual contact; and performing a secondary cure of the partially-cured resin at the joint surfaces using an application of radiant energy, so as to further cure the partially-cured resin and bond the sub-components to each other, thereby forming the component.

A stiffened part formed from at least two members of thermoset composite material including at least one body of a first structure and optionally a second structure. A manufacturing method includes: forming a fibre preform and impregnating each body of the first structure with thermosetting resin or forming a pre-impregnated fibre preform to obtain a body formed from uncured thermosetting composite material supported by a mandrel; optionally partially or fully polymerising at least one body supported by a mandrel; optionally, providing the second structure formed from uncured, partially uncured or fully uncured thermosetting composite material; optionally, depositing a layer of uncured thermosetting adhesive on an area where a fully cured member makes contact with another member of the part; joining the members, each member being juxtaposed with; or stacked upon, at least one other member; fully curing the assembly by heat treatment; removing the mandrel from each fully cured body.