Sika Technology Ag

Jürgen Finter

Andreas Kramer

Ulrich Gerber

Karsten Frick

Jan Olaf Schulenburg

Matthias Gössi

Norman Blank

Vincent Belpaire

Urs Rheinegger

Rui Xu-Rabl

Peter W Merz

Elyes Jendoubi

Yves Meier

Jeannette Clifford

Bernd Burchardt

Heat-curing epoxy resin compositions are characterized by high impact strength, good storage stability, and a low curing temperature. The epoxy resin compositions are suitable for use as a construction shell adhesive and for producing structural foams. They can already be cured in so-called bottom-baking conditions. Furthermore, it has been found that the use of an accelerator of the formula (Ia) or (Ib) results in an increase of the impact strength of heat-curing epoxy resin compositions.

Heat-curing epoxy resin composition containing non-aromatic ureas as accelerator

A composition having at least one structural adhesive and at least one chemically crosslinked elastomer based on the silane-functional, non-polar polymer, said elastomer being provided in the form of a penetrating polymer network in the structural adhesive. Self-supporting adhesive bodies, particularly in the form of adhesive tapes, can be produced from such compositions and can be used for structural bonds and to reinforce metal structures.

Self-supporting adhesive body for structural bonds

In a reinforcing system for reinforcing a cavity of a structural element, a support element is connected to the structural element in the structural element for reinforcement purposes. The support element has channels, an adhesive is disposed in the cavity between the support element and the structural element, and the adhesive can be introduced into the cavity between the support element and the structural element by means of the channels.

Reinforcing system for reinforcing a cavity of a structural element

What is described is a polymer which is a polyurethane polymer having blocked isocyanate groups or a reaction product of said polyurethane polymer with at least one epoxy resin, where the polyurethane polymer having blocked isocyanate groups is an addition product formed from at least one polyisocyanate and at least one polyester polyol, wherein the isocyanate groups of the addition product have been blocked by reaction with at least one aromatic compound having at least one hydroxyl group. Such a polymer is suitable as an impact modifier in epoxy resin compositions, especially when they are used as adhesives or structural foams. The polymer improves the corrosion resistance and vertical expansion of the epoxy resin composition.

Polyester prepolymers as impact modifiers in epoxy formulations

A composition, including at least one curable structural adhesive, and at least one thermoplastic elastomer, wherein the thermoplastic elastomer is present in the structural adhesive as penetrating polymer network. Such a composition constitutes a so-called shape memory material and is suitable for reinforcing cavities in structural components, such as, for example, in automobile bodies.

Shape memory material based on a structural adhesive

The present invention relates to a butadiene/acrylonitrile copolymer CTBN, modified by epoxy solid resin and terminated by carboxyl groups, the terminal epoxy groups thereof also having optionally been reacted. A polymer of this type is used in particular as an impact strength improving agent in epoxy resin compositions and has proven to be particularly advantageous for gluing on or of metal surfaces. It results in a significant reduction of the infiltration with corrosion, which in turn ensures a long-lived adhesive bond.

Impact strength improving agent for epoxy resin compositions

A composition is described which includes A) a chain-extended prepolymer, which can be obtained from the reaction of a) a polymer containing at least one amino, thiol or hydroxyl group, b) at least one polyisocyanate and c) at least one alkoxylated bisphenol as chain extender, and optionally d) an epoxide compound containing a primary or secondary hydroxy group, said compound containing a primary or secondary hydroxyl group, or at least one epoxy resin A which contains this epoxide compound, and optionally B) an epoxy resin B. The composition is suitable as a toughener or as an A component of a 2k epoxy resin adhesive which contains this toughener. The adhesive is suitable particularly for bonding in windmills.

Prepolymer toughener for crack-resistant adhesives for windmills

Heat-curable epoxy resin compositions and the use thereof, for example, in motor vehicle construction and sandwich panel construction, are disclosed. Exemplary heat-curable epoxy resin compositions include, in addition to epoxy resin components A1, optionally A2, a hardener component B, a carboxylic acid C and a hydroxyalkylamide or hydroxyalkylurea H, an accelerator E for activation of the conversion of components A1, A2 and B. The compositions and the structural foams produced therefrom are notable for high mechanical strength, high glass strength and good adhesion capacity on metallic and nonmetallic substrates, and it is possible at the same time to dispense with the use of toxic or inflammable blowing agents.

Heat curable epoxy resin composition with water as foaming agent

The disclosure relates to the field of two-component epoxy resin compositions and to the use thereof as a repair adhesive, in particular in vehicle manufacturing. The two-component epoxy resin compositions according to the disclosure contain a curing component K2, which comprises between 1 and 10 wt. % of an amino group-terminated polyamide B, together with an epoxy resin component K1. The compositions show that the impact resistance is highly increased while an acceptable sheer strength is simultaneously retained.

Two-component structural adhesive which is impact resistant at room temperature

The invention relates to compositions containing at least one epoxide adduct A that comprises an average of more than one epoxide group per molecule, at least one polymer B of formula (I), at least one thixotropic agent C based on a urea derivative in a non-diffusing carrier material, and at least one hardener D for epoxy resins, which is activated at an increased temperature. Said composition is used especially as an adhesive and is provided with an extraordinarily high impact peel working value, especially at low temperatures. The invention further relates to epoxide group-terminal impact strength modifiers of formula (I), which significantly increase the impact resistance in epoxy resin compositions, particularly two-component epoxy resin compositions.

Thermally hardenable epoxy resin composition having an improved impact resistance at low temperatures

The present disclosure relates to impact strength modifiers, the derivative products thereof, and the use thereof in producing two-component epoxy resin compositions. The disclosure in particular relates to amino group terminated impact strength modifiers prepared by reacting a polyurethane prepolymer having isocyanate groups, a primary diamine, and optionally at least one Michael acceptor. The two-component epoxy resin compositions thus formulated are characterized by a great increase in impact strength while retaining an acceptable tensile shear strength. The impact strength modifiers according to the disclosure and the epoxy resin compositions comprising same are in particular suitable for vehicle manufacturing.

Amino group terminated impact strength modifier and use thereof in epoxy resin compositions

An oligomeric condensation product can be obtained from at least one (hydroxymethyl)phenol of general formula (I), in which Ris hydrogen or &#x2014;CH, Ris &#x2014;CHOH, and Ris hydrogen or &#x2014;CH, at least one polyamine, and optionally at least one phenol compound having two centers reactive by means of a reaction with the methylol groups of the (hydroxymethyl)phenol.

Reactive polymer catalysts for 2-component epoxy resin systems

In the case of a reinforcing system for reinforcing a cavity of a structural element, a carrier element is connected to the structural element in the structural element for reinforcement purposes. The carrier element has channels, an adhesive is disposed in the cavity between the carrier element and the structural element, and the adhesive can be introduced into the cavity between the carrier element and the structural element by means of the channels.

A composition including at least one curable structural adhesive, and at least one chemically crosslinked elastomer on the bases of a silane-functional polymer, wherein the elastomer is in the form of an interpenetrating polymer network in the structural adhesive. The composition can be used to form a shape-memory material and is suitable for reinforcing cavities in structural components such as, for example, in automobile bodies.

Shape-memory material based on a structural adhesive

The present invention relates to epoxy group-terminated polymers of the formula (I). Said epoxy group-terminated polymers are suited extremely well as impact resistance modifiers, particularly in epoxy resin compositions. They are particularly suited for use in heat-curing epoxy resin adhesives. It has been found that such epoxy resin compositions not only have excellent mechanical properties and high glass transition temperatures, but also above all improved impact resistance properties, both at room temperature and at low temperatures. 

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Zurich, Switzerland

Jürgen Finter