Abstract: Disclosed herein is a solvent-based bonding primer composition containing one or more organic solvents, one or more epoxy resins, one or more curing agents, a silane compound, and a low amount of core-shell rubber particles in nanometer size, submicron or micron size. Also disclosed is a method of applying the solvent-based bonding primer composition onto a metallic surface of a first substrate prior to bonding the metallic surface to a second substrate via a curable adhesive.

Abstract: A surfacing material that can provide improved UV resistance while providing good surface properties. The surfacing material includes a resin layer formed from a curable resin composition containing: (A) one or more cycloaliphatic epoxy resin(s), each having two or more epoxy groups per molecule; (B) an epoxy-amine adduct having two or more epoxy groups per molecule and obtained by a reaction of (i) an epoxy compound having two or more alicyclic epoxy groups per molecule with (ii) an amine compound having two or more amino groups per molecule; (C) a curing agent and/or a catalyst; (D) ceramic microspheres; and (E) a flow control agent in the form of inorganic particles, which are not ceramic microspheres.

Abstract: A surfacing material that is capable of ultraviolet (UV) protection. The surfacing material is a multilayer structure composed of a woven peel ply fabric interposed between a first curable resin layer and a second curable resin layer. The surfacing material is designed to be co-cured with a composite substrate, for example, a prepreg layup. Upon curing, the peel ply fabric combined with the outer thermoset layer function as a UV protective layer. When the peel ply fabric and the outer thermoset layer are removed, a paint-ready surface is revealed. Such surface does not require any surface preparation prior to painting.

Abstract: A bonding method for joining two structural parts using a curable adhesive layer having a fibrous veil embedded therein. The fibrous veil carries a polymeric binder, which is in a solid phase at room temperature (20° C.-25° C.) and is capable of dissolving into the adhesive composition during curing thereof.

Abstract: A low-density, halogen-free epoxy composition that is flame-resistant upon curing and is suitable for use as a potting compound. The epoxy composition includes: (a) an epoxy component; (b) at least one curative; (c) at least one latent curing accelerator; (d) a toughening component that includes nano-sized core shell rubber (CSR) particles having particle size of less than 1 micron; (e) a fire-retardant component that is halogen-free; and (f) hollow microspheres for reducing the density of the composition. The fire-retardant component includes a mixture of: (i) at least one polyphosphate; (ii) at least one metal borate; and (iii) at least one compound selected from alkaline earth metal hydroxides and aluminum hydroxides.

Abstract: A method for surface preparation of a composite substrate prior to adhesive bonding. The surface preparation method includes applying a resin-containing peel ply onto a composite substrate, followed by co-curing. The resin-containing peel ply contains a non-removable textile carrier and a removable woven fabric embedded therein. After co-curing, the peel ply is removed from the composite substrate such that the removable woven fabric is removed but the non-removable textile carrier and a film of residual resin remain on the composite substrate, thereby creating a modified, bondable surface on the composite substrate. The composite substrate with the modified surface can be bonded to another composite substrate, whereby the textile carrier remains an integrated part of the final bonded structure.

Abstract: A method for surface preparation of a composite substrate prior to adhesive bonding. The surface preparation method includes applying a resin-containing peel ply onto a composite substrate, followed by co-curing. The resin-containing peel ply contains a non-removable textile carrier and a removable woven fabric embedded therein. After co-curing, the peel ply is removed from the composite substrate such that the removable woven fabric is removed but the non-removable textile carrier and a film of residual resin remain on the composite substrate, thereby creating a modified, bondable surface on the composite substrate. The composite substrate with the modified surface can be bonded to another composite substrate, whereby the textile carrier remains an integrated part of the final bonded structure.

Abstract: A surfacing material that is capable of ultraviolet (UV) protection. The surfacing material is a multilayer structure composed of a woven peel ply fabric interposed between a first curable resin layer and a second curable resin layer. The surfacing material is designed to be co-cured with a composite substrate, for example, a prepreg layup. Upon curing, the peel ply fabric combined with the outer thermoset layer function as a UV protective layer. When the peel ply fabric and the outer thermoset layer are removed, a paint-ready surface is revealed. Such surface does not require any surface preparation prior to painting.

Abstract: A surfacing material that is capable of ultraviolet (UV) protection and self-releasing from a mold surface. The surfacing material is a multilayer structure composed of a curable resin layer laminated to a self-releasing layer. The surfacing material is designed to be co-cured with a composite substrate, for example, a prepreg layup. After co-curing, the composite part surfaced with the surfacing material is releasable from the mold surface with ease. The self-releasing layer functions as a UV blocking layer until the cured composite substrate is ready for painting. When the self-releasing layer removed, a paint-ready surface is revealed. Such surface does not require any surface preparation prior to painting.

Abstract: A bonding method for joining two structural parts using a curable adhesive layer having a fibrous veil embedded therein. The fibrous veil carries a polymeric binder, which is in a solid phase at room temperature (20° C-25° C.) and is capable of dissolving into the adhesive composition during curing thereof.

Abstract: A method for bonding composite substrates is disclosed. A curable surface treatment layer is applied onto a curable composite substrate, followed by co-curing. After co-curing, the composite substrate is fully cured but the surface treatment layer remains partially cured. The surface treatment layer may be a resin film or a peel ply composed of resin-impregnated fabric. If a peel ply is used, the peel ply is peeled off after co-curing, leaving behind a remaining thin film of partially cured resin. A subsequent dry physical surface treatment, such as plasma, is carried out to physically modify the surface of the surface treatment layer. After dry physical surface treatment, the composite substrate is provided with a chemically-active, bondable surface, which is adhesively bonded to another composite substrate to form a covalently-bonded structure.

Abstract: A water-based bonding primer composition and a method of applying the same onto a metallic surface prior to adhesive bonding. The bonding primer composition is a water-based dispersion containing water, one or more epoxy resins, one or more curing agents, a silane compound, a low amount of propylene carbonate (PC), and optional additives. The bonding primer composition can form substantially smooth films by spraying, and at the same time, meet environmental regulations and provide high bonding performance.

Abstract: A water-based bonding primer composition and a method of applying the same onto a metallic surface prior to adhesive bonding. The bonding primer composition is a water-based dispersion containing water, one or more epoxy resins, one or more curing agents, a silane compound, a low amount of propylene carbonate (PC), and optional additives. The bonding primer composition can form substantially smooth films by spraying, and at the same time, meet environmental regulations and provide high bonding performance.

Abstract: A water-based bonding primer composition and a method of applying the same onto a metallic surface prior to adhesive bonding. The bonding primer composition is a water-based dispersion containing water, one or more epoxy resins, one or more curing agents, a silane compound, a low amount of propylene carbonate (PC), and optional additives. The bonding primer composition can form substantially smooth films by spraying, and at the same time, meet environmental regulations and provide high bonding performance.

Abstract: A composite bonding process is disclosed. At least one of two curable, resin-based composite substrates is partially cured to a degree of cure of at least 10% but less than 75% of full cure. The composite substrates are then joined to each other with a curable adhesive there between. Co-curing of the joined substrates is carried out to form a bonded composite structure, whereby the adhesive is chemically bonded to and mechanically diffused with the resin matrix of the composite substrates, resulting in a chemically bonded interface between the adhesive and each composite substrate. Furthermore, bonding can occur with the presence of contaminants on the joined surfaces.

Abstract: A water-based bonding primer composition and a method of applying the same onto a metallic surface prior to adhesive bonding. The bonding primer composition is a water-based dispersion containing water, one or more epoxy resins, one or more curing agents, a silane compound, a low amount of propylene carbonate (PC), and optional additives. The bonding primer composition can form substantially smooth films by spraying, and at the same time, meet environmental regulations and provide high bonding performance.

Abstract: A composite bonding process is disclosed. At least one of two curable, resin-based composite substrates is partially cured to a degree of cure of at least 10% but less than 75% of full cure. The composite substrates are then joined to each other with a curable adhesive there between. Co-curing of the joined substrates is carried out to form a bonded composite structure, whereby the adhesive is chemically bonded to and mechanically diffused with the resin matrix of the composite substrates, resulting in a chemically bonded interface between the adhesive and each composite substrate. Furthermore, bonding can occur with the presence of contaminants on the joined surfaces.

Abstract: Novel aromatic ether ketone diamine compounds and methods for their preparation are disclosed which comprise from about 3 to 8 aromatic rings interspersed with ether and ketone linkages. The novel ether ketone diamine compounds are useful as monomeric starting materials for the preparation of useful intermediates and useful thermoplastic and high temperature resistant polymers. In preferred embodiments, the novel ether ketone diamines are useful as curing agents for epoxy resin compositions and composite materials.

Abstract: N,N'-dimethyl aromatic diamines are prepared from the corresponding diprimary amines via a two step synthesis forming first the corresponding di-succinylimidomethylamine and then reductively cleaving the succinylimido group. The products are useful, e.g., as epoxy curing agents.

Abstract: A method for making polyimide polymers is provided by effecting reaction between an aliphatically unsaturated imide, such as maleimide, formaldehyde, and an organic polyamine, for example trimethylene bis(4-aminobenzoate), for example in refluxing ethanol. The polyimides produced by the simple one-step method are pure, and exhibit superior toughness, and reduced shrinkage upon cure by heating. The new product are useful as molding compounds, laminating resins, and the like, being especially suitable for airplane parts, advanced composites, high performance adhesives and printed circuit boards.