Abstract:
PROBLEM TO BE SOLVED: To provide an epoxy-based adhesive containing a toughening agent and to provide a method of applying such adhesive using a streaming process.SOLUTION: An adhesive composition comprises: one or more epoxy resins; one or more rubber-modified epoxy resins; the reaction product of one or more isocyanate terminated prepolymers and one or more capping compounds having one or more phenolic, benzyl alcohol, aminophenyl or, benzylamino moieties, wherein the reaction product is terminated with the capping compound; and optionally fillers, adhesion promoters, wetting agents and rheological additives useful in epoxy adhesive compositions. The adhesive composition has a viscosity at 45°C of 20 to 400 Pas by performing curing at a temperature of 100°C or greater. The adhesive composition is applied to a base material.
Abstract:
PROBLEM TO BE SOLVED: To provide a thermosetting structural epoxy adhesive having excellent storage stability.SOLUTION: The following compound is used as a reinforcement. The compound comprises an elastomeric prepolymer residue selected from the group of a polyurethane, a polyurea and a polyurea polyurethane having isocyanate end groups. The isocyanate end groups of the prepolymer residue are capped by a capping compound selected from the group consisting of a primary aliphatic, cycloaliphatic, heteroaromatic and aromatic aliphatic amine, a secondary aliphatic, cycloaliphatic, aromatic, heteroaromatic, and aromatic, aliphatic amine, a thiol and an alkyl amide. The capping compound is bound to the end of the polymer chain of the elastomeric prepolymer in such a manner that the end to which it is bonded no longer has a reactive group.
Abstract:
Epoxy adhesive compositions contain a heat-activatable catalyst. The heat-activatable catalyst includes a tertiary amine catalyst and a novolac resin that has a weight average molecular weight of at least 3000. One-component epoxy adhesive formulations that contain the heat-activatable catalyst have unexpectedly good storage stability.
Abstract:
The present invention provides an acrylic-epoxy hybrid two part adhesive composition for structural metal bonding such as closure hem flange bonding in an automotive line. The new composition offers several performance benefits over the current commercially available adhesive compositions in that it is pre-curable by induction. The new composition has high static and dynamic strength after passing the e-coat oven on oily metal surfaces with reduced failure mode and provides bubble-less adhesion to electro-galvanized coated steels. The new composition also has good initial strength values if cured at room temperatures only.
Abstract:
A heat-curable structural adhesive includes a non-rubber-modified epoxy resin, a reaction product of a carboxyl- or amine-terminated butadiene polymer or copolymer and a bisphenol F-based epoxy resin, a elastomeric toughener containing capped isocyanate groups, one or more epoxy curing agents a moisture scavenger and a heat activatable catalyst comprising a mixture of a solid or liquid tertiary amine compound that has a boiling temperature of at least 130°C and a novolac resin. The structural adhesive develops excellent bonding properties when cured at moderate temperatures, especially from 120 to 170°C, and in addition performs very well in environmental aging stress testing. The adhesive is particularly good for bonding aluminum to another metal, or bonding aluminum to aluminum.
Abstract:
A heat-curable structural adhesive includes at least one non-rubber-modified epoxy resin; an optional rubber or toughener, one or more epoxy curing agents, one or more epoxy curing catalysts; and a flame retardant mixture that includes (i) alumina trihydrate, (ii) zinc borate and (iii) melamine or a melamine derivative. The structural adhesive is useful for bonding metals to other materials or metals to other metals. The structural adhesive strongly resists ignition when welding is performed in the presence of the uncured material, and does not interfere significantly with weld performance.