Evonik Degussa Gmbh

Evonik Roehm Gmbh

Evonik Operations Gmbh

Evonik Rohm Gmbh

Goldschmidt Gmbh

Karlsruher Institut Fur Technologie

Evonik Goldschmidt Corporation

Friedrich Georg Schmidt

Emmanouil Spyrou

Stephan Kohlstruk

Helmut Ritter

Steffen Schaffer

Stefan Hilf

Christopher Barner-Kowollik

Jiawen Zhou

Holger Loesch

Kim Klaus Oehlenschlaeger

Martina Ortelt

Gerda Grund

Sandra Reemers

Andre Hennig

Nathalie Guimard

Guenter Schmitt

Rainer Lomoelder

Dirk Fuchsmann

Matthias Seiler

Hinnerk Gordon Becker

Dirk Hoppe

Andreas Pawlik

Hans Guenther Wey

Eike Langkabel

Werner Grenda

Stefan Bernhardt

Elke Gollan

Britta Kohlstruk

Bernd Weyershausen

Heike Heeb

Florian Hermes

Günter Schmitt

Hans-Dieter Zagefka

Markus Schwarz

Susanne Kreischer

Werner Freitag

Simon Krause

Antje May

Andrew John Inglis

Dorothea Staschik

Sebastian De Nardo

Hubert Johannes Bahl

Leena Nebhani

Harald Häger

Marina Grammenos

Jan Mueller

Stefan Spange

Frank-Martin Petrat

Rebecca Pieroth

Sibylle Planitz-Penno

André Hennig

Ozcan Altintas

Peter Dürre

Simone Lederle

Wilfried Schmidt

Michael Spittler

Thomas Eurich

Michael Kube

Katharina Cielaszyk

Martin Kothe

Birte Olland

ÖZcan Altintas

Ralf-Jörg Fischer

Kim Klaus ÖHLENSCHLÄGER

Hans Günther Wey

Oezcan Altintas

Andrea Vöcker

Katja Hase

Ingmar Polenz

Zuhal Tuncay

Provided is a storage-stable polyurethane prepegs and mouldings produced therefrom composed of polyurethane compositions with liquid resin components, preferably liquid polyols. A prepeg contains(A)a fibrous support and (B)a matrix material containing a reactive polyurethane composition. The polyurethane composition contains a mixture of a liquid resin component(b)having a functional group reactive towards an isocyanate and having a glass transition temperature(Tg)or melting point below 25&#xb0; C., with a hydroxyl number of 50 to 2000 mg KOH/gram, and a curing agent(a)comprising a di- or polyisocyanate internally blocked or blocked with a blocking agent. In addition, the polyurethane composition contains 0.6 to NCO equivalents or 0.3 to 1 uretdione group in (a) for each functional group of (b).

Storage-stable polyurethane prepregs and mouldings produced therefrom composed of a polyurethane composition with liquid resin components

The invention concerns specifically emulsion polymers which are intraparticulately crosslinked via a hetero-Diels-Alder (HDA) mechanism. The crosslinked polymers can then be wholly or partly decrosslinked by thermal processing, for example in the form of a composite matrix, via a retro-Diels-Alder or retro-hetero-Diels-Alder reaction and interparticulately recrosslinked on cooling. This makes it possible to prepare long shelf life prepregs for composites. But it is also possible to thus realize other materials that have thermoset properties at use temperature but thermoplastic processing properties at a higher temperature.

Kit for producing composite semi-finished products comprising reversibly crosslinked polymer emulsions

The invention relates to a process for producing storage-stable polyurethane prepregs and to moldings (composite components) produced therefrom. The prepregs and, respectively, components are produced by mixing (meth)acrylate monomers, (meth)acrylate polymers, hydroxy-functionalized (meth)acrylate monomers and/or hydroxy-functionalized (meth)acrylate polymers with uretdione materials. Photoinitiators can also optionally be added. This mixture or solution is applied by known processes to fiber material, e.g. carbon fibers, glass fibers or polymer fibers, and is polymerized with the aid of radiation or of plasma methods. Polymerization, e.g. at room temperature or at up to 80&#xb0; C., gives thermoplastics or thermoplastic prepregs, and these can subsequently also be subjected to forming processes. The hydroxy-functionalized (meth)acrylate constituents can then be crosslinked with the uretdiones already present within the system, by use of elevated temperature. It is thus possible to produce dimensionally stable thermosets or dimensionally stable crosslinked composite components.

Composite semifinished products and mouldings produced therefrom and directly produced mouldings based on hydroxy-functionalized (meth)acrylates and uretdiones which are crosslinked by means of radiation to give thermosets

The invention relates to low molecular mass products and to the use thereof as reversible or permanent low-temperature crosslinkers in Diels-Alder reactions.

Low molecular weight products and use thereof as reversible or permanent low-temperature crosslinking agent in Diels-Alder reactions

The invention relates to a method for producing storage-stable polyurethane prepregs and molding bodies produced therefrom (composite components), which can be obtained by a method using a polyurethane composition in solution and by impregnation of fiber-reinforced materials such as of woven fabrics and laid scrim using reactive polyurethane compositions.

Process for the production of storage-stable polyurethane prepregs and mouldings produced therefrom from dissolved polyurethane composition

Provided is a prepreg composed of a fibrous substrate impregnated with a reactive or highly reactive polymer composition as a matrix material. The reactive or highly reactive polymer composition contains a (meth)acrylate-based resin comprising at least one of a hydroxyl group, an amine group, a thiol group, an initiator and/or accelerator, and a di- or polyisocyanate which has been internally capped, capped with a capping agent, or a combination thereof. The (meth)acrylate-based resin contains from 20% by weight to 70% by weight of at least one (meth)acrylate monomer and from 1% by weight to 50% by weight of at least one prepolymer.

Composite semifinished products, molded parts produced therefrom, and molded parts produced directly based on hydroxy-functionalized (meth)acrylates, which are cross-linked by means of uretdiones in a thermosetting manner

A method for the reversible crosslinking of, for example, adhesives or coating materials, and a composition stable on storage at room temperature for implementing the crosslinking reaction. The reversible crosslinking method allows very rapid crosslinking even at a low first temperature, and undoing of the crosslinks at higher temperatures, thereby recovering thermoplastic processability and, for example, allowing the originally bonded substrates to be parted from one another again easily. A particular aspect is that a plurality of cycles of crosslinking and undoing of the crosslinks are possible with the present system. A feature of the system used for the reversible crosslinking is that it contains two components, A and B, where component A is a compound having at least two protected dithioester functionalities, preferably cyanodithioester functionalities, and component B is a compound having at least two diene functionalities.

Functional materials with reversible crosslinking

The invention relates to the use of polyolefins modified with one or more silanes as adhesion promoters for the production of flat glass/glass, glass/plastic, or plastic/plastic laminates, to corresponding laminates, and to displays containing the laminates according to the invention.

Use of silane-modified polyolefins as adhesion promoters for the production flat laminates

In the present process, reversibly crosslinking composites or storage-stable prepregs are produced by means of a hetero Diels-Alder reactions (HDA,) for example of PMMA polymers. At slightly elevated temperature, these prepregs can be reversibly decrosslinked again by a retro hetero Diels-Alder reaction so that they become moldable. The back-reaction to products which are again crosslinked or high molecular weight then takes place at room temperature.

Pseudothermoplastic, self-crosslinking composites

The present invention relates to an innovative method for controlling the viscosity of, for example, adhesives or coating formulations. The method for controlling viscosity allows very rapid thermoplastic curing of a formulation even at room temperature and a significant reduction in the viscosity at higher temperatures, thereby regaining the capacity for simple processing and allowing, for example, the originally bonded substrates to be separated from one another again with ease. A particular aspect in this context is that a plurality of cycles of thermoplastic curing and a significant reduction in the viscosity are possible with the present system.

Functional materials with controllable viscosity

The present invention relates to innovative materials which are reversibly crosslinkable by means of a thermoreversible mechanism and/or whose viscosity is reversibly adjustable. Through the use of bishydrazones or conjugated bis-Schiff bases as diene components in aza-Diels-Alder reactions, functional materials are generated that feature controllable viscosity and/or reversible crosslinking.

Functional materials having a controllable viscosity or reversible crosslinking via aza Diels-Alder reactions with bishydrazones or conjugated bis-Schiff bases

The invention relates to the use of a powder made of a polymer, which of two or more components with functionalities suitable for Diels-Alder reactions, or of a powder mixture (dry blend) made of powders respectively of at least one of the reactive components, where these together enter into the Diels-Alder reaction with one another and are capable of a retro-Diels-Alder reaction, in a rapid-prototyping process. The invention further relates to moldings produced with use of said polymer powder through a layer-by-layer shaping process in which regions of a powder layer are melted selectively. The molding here can be removed from the powder bed after cooling and hardening of the regions previously melted layer-by-layer.

Polymer powder for producing three-dimensional objects

The present invention relates to innovative materials which can be crosslinked by means of two different crosslinking mechanisms, the first crosslinking mechanism being an irreversible crosslinking. The second crosslinking mechanism is a thermoreversible mechanism. As a result of this thermoreversible change in the arc length, properties of the crosslinked material can be decisively changed and controlled, including flexibility, elasticity and other mechanical properties, but also chemical properties, the gas permeability and vapor permeability and storage capacity of the network. In this way it would be possible, for example, to store energy sources such as fuels.

Materials having a controllable degree of crosslinking

The present invention relates to an innovative method for the reversible crosslinking of, for example, adhesives or coating materials. The reversible crosslinking method allows very rapid crosslinking even at room temperature and undoing of the crosslinks at higher temperatures, thereby regaining the capacity for thermoplastic processing and allowing the originally bonded substrates to be separated from one another again with ease. A particular aspect in this context is that a plurality of cycles of crosslinking and undoing of the crosslinks are possible with the present system.

The invention relates to prepregs and composite components (molding) produced therefrom at a low temperature, obtainable by using powdery highly reactive polyurethane compositions containing uretdione groups, with specific catalysts.

Prepegs and molded bodies produced thereof at low temperature

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Haltern am See, Germany

Friedrich Georg Schmidt