About Crosslinkers

What are crosslinkers? What is isophorone chemistry?

Get all the answers to your burning questions directly from the inventor of isophorone chemistry

Crosslinking makes the difference

In a well-linked network, by connecting many individuals, a continuously stable performance can be assured and often even the positive extra can be achieved.
The idea of crosslinking can be applied to many applications. E.g. in a coating system single molecules have the potential to perform outstandingly, but crosslinked molecules surpass the level of superior performance.

Non-crosslinked coatings

Polymer chains are open to environmental influences.

Without crosslinking, a coating will be easily influenced by environmental impacts and will consequently lead to the damaging of the substrate.

Crosslinked coatings

Crosslinked polymeric network
build a protective structure.

Crosslinkers increase the stability of the coating and improve the resistance towards environmental impacts.

Evonik is the pioneer in isophorone chemistry

Evonik is the inventor of isophorone chemistry and it all started with a simple question: How can we utilze aceton?

The development of the new solvent isophorone resulted from the search for ways in which to dispose of or recycle acetone. Production of the solvent isophorone started in 1962 in the Herne nitrogen works of Hibernia AG, a predecessor company of todays Evonik Industries AG.

Because of its special chemical structure, Isophorone serves as starting material for production of several chemicals. Today Evonik covers the entire value chain: isophorone, diamine, as well as di-isocyanate and polyisocyanate.

Isophorone is a largely colorless liquid that is used, among other things, in the coating, printing ink, and adhesive industries, due to its outstanding solvent properties. It is used in a wide variety of applications, including as a starting material for disinfectants and vitamin E. Secondary products of isophorone are used in car headlights to ensure high temperature resistance and a special look.


  • Plant protection products
  • Sunscreens
  • Solvents for printing inks
  • Headlights

The main applications for isophorone diamines are heavy-duty coatings for industrial flooring, followed by high-quality and durable anti-corrosion coatings, both of which are attractive growth markets. However, demand is rising fastest for isophorone diamine for high-performance composites. For example, the resin used in the construction of rotor blades for wind turbines contains two components—an epoxide resin and a curing agent comprised mainly of isophorone diamine. This component optimizes resin curing and the stability of the composite, which is essential for the production of large rotor blades.


  • Wind turbine rotor blades
  • Floor coatings
  • Marine coatings
  • Composite materials for pipes

Isophorone diisocyanate (IPDI) is the next stage of refinement—one that fulfills all of the preconditions for the production of lightweight and weather-
resistant polyurethane. In cars, IPDI is used in “spray skins,” for example. Spray skins include coatings for the dashboard and other plastic parts. In addition to high resistance, such components now


  • Urethane acrylates and polyurethane emulsions for coatings and adhesives
  • Elastomers for sealants and in the automotive sector

The secondary products of IPDI are referred to as derivatives. These are crosslinkers for various types of polyurethane coating - either powder, water-based or solvent-based. IPDI derivatives make such coatings very resistant to weathering and chemicals.

Powder coatings are especially efficient to apply and give bicycle frames, for example, a high-quality appearance. Such coatings are also used to decorate window profiles with a special production process (transfer printing).


  • Coil coatings
  • Can coatings
  • Automotive refinishing coatings
  • Powder coatings

History of isophorone chemistry

Today Evonik covers the whole isophorone chemistry value chain and offers a broad range of products and proven experience in the areas of coatings, adhesives as well as for high performance elastomers and composites.

This all started almost 60 years ago in Herne, Germany.

Production of the solvent isophorone starts in 1962 in the Herne (Germany) nitrogen works of Hibernia AG. The development of the new solvent results from the search for ways in which to dispose of or recycle acetone.

Isophorone production is carried out in what will later become the Herne, Germany, plant of Evonik Industries AG and is at this time known as the Hibernia factory Herne I. Putting the first production plant into operation in 1967 signaled the start of acetone chemistry in Herne that was intended to position the site for the future and that still provides it with security today.

When VEBA AG reorganized its chemical business, the Herne plants were transferred to Hüls AG in 1979 and so was the Isophorone product family.

By commissioning the second integrated isophorone line, Evonik is able to increa-se the production capacities of isophorone twofold.

By commissioning the second integrated isophorone line, Evonik is able to increase the production capacities of isophorone twofold.

By commissioning the second integrated isophorone line, Evonik is able to increa-se the production capacities of isophorone twofold.

The fifth production facility goes into operation in Shanghai (China). It focuses on the Asian market.

Today Evonik has a network of integrated world-scale production facilities in Herne and Marl (Germany), Antwerp (Belgium), Mobile (AL, USA) and Shanghai (China) enabling the company to achieve cost leadership in the technologically advanced production processes for isophorone products.