FAQ Knowledge Epoxy Resin
What is Epoxy Resin?
Epoxy resin is a high-performance material that belongs to the group of thermosetting plastics. It is typically formed by combining a resin with a hardener, which triggers a chemical reaction. During this process, the material cures and forms a stable, three-dimensional cross-linked structure. The result is a thermosetting polymer known for its robustness and long-term stability.
There are two main types of epoxy systems:
- One-component (1K): Ready to use and does not require mixing before application
- Two-component (2K): Consists of a resin and a hardener that must be mixed before use
Once cured, epoxy resin becomes a highly durable material with excellent long-term stability. Its key properties include:
- High mechanical strength, including strong tensile and compressive performance
- Excellent chemical resistance to oils, solvents, and aggressive environments
- Reliable adhesion to materials such as metal, glass, ceramics, and plastics
- Resistance to temperature, moisture, and environmental influences
- Electrical insulation properties, making it ideal for electronic applications
- Thermal conductivity, depending on the formulation
Thanks to this combination of properties, epoxy resin is widely used in applications such as bonding, coating, sealing, and protecting components across a broad range of industries.
What can epoxy resins do?
Epoxy resin is an exceptionally versatile material used across a wide range of industries thanks to its outstanding performance characteristics. As a thermosetting plastic, it forms a permanently cross-linked structure after curing, resulting in exceptional strength, durability, and stability. The product portfolio by EPOXONIC also includes specialized variants such as flexible epoxy systems.
Its key capabilities include:
- Strong adhesion to materials such as metal, concrete, ceramics, and plastics
- High mechanical strength and long-term durability
- Excellent chemical resistance against oils, solvents, and aggressive environments
- Temperature and moisture resistance, even under demanding conditions
- Electrical insulation properties, making it ideal for electronic applications
- Adjustable flexibility, ranging from rigid to highly elastic formulations
Thanks to this unique combination of properties, epoxy resin can be used for bonding, coating, sealing, casting, and protecting components in highly demanding applications.
Flexible epoxy resin – is it possible?
Flexible epoxy resin is a specialized material that extends the capabilities of conventional epoxy systems. While standard potting resin cures into a hard and rigid material, flexible epoxy resin is specifically engineered to provide a certain degree of elasticity.
Curing typically takes place through heat curing combined with a flexibilizer developed by EPOXONIC. This ensures a reliable and durable cross-linked structure. The development department is currently working on a flexible resin system that can be processed at lower curing temperatures.
The resulting flexible epoxy resins retain many of the advantageous properties of their rigid counterparts, such as chemical resistance and excellent adhesion, while additionally offering improved shock absorption and vibration damping. These characteristics make them ideal for applications where movement or mechanical stress must be accommodated without compromising long-term durability.
Flexible epoxy resin is often compared to silicone due to its similar consistency and elasticity. However, unlike silicone, epoxy provides stronger adhesion to a wide range of substrates and higher resistance to chemical exposure, making it a superior choice in many technical and industrial applications.
How are new epoxy resin products developed?
In most cases, the base raw material used is bisphenol A diglycidyl ether (DGEBA), one of the most common epoxy resin building blocks. Starting from this foundation, an almost unlimited range of formulations can be created by adding different raw materials and modifiers.
Depending on the selected formulation, epoxy systems can be specifically designed to be e.g.:
- Accelerated in curing speed
- Rheologically adjusted (e.g., viscosity and flow behavior)
- Toughened or flexibilized
- Thermally conductive
- Electrically conductive
These tailored properties are achieved by incorporating suitable additives, fillers, and curing agents that influence the rheology, curing behavior, and final performance of the material.
Based on the specific requirements of each application, we develope customized epoxy resin formulations. After curing, these formulations result in optimized products that provide the desired mechanical, chemical, thermal, or electrical performance.
How are epoxy resins actually cured?
One way of curing epoxy resins is to react with amines.
There is a wide range of amines that can be used for curing. Whether aliphatic, cycloaliphatic, aromatic, long-chain or short-chain, each of these amines can be reacted with epoxy resin. Depending on the application and hardener used, various properties are possible: room temperature curing or hot curing, glass transition temperature in the range of 50 - 150°C, 2-component systems (or 1-component systems).
A good example of this is our EPOXONIC 382.
Anhydride curing
One way of curing epoxy resins is to react with anhydrides.
In anhydride curing, the anhydride is opened in the first step and reacts with the diglycidyl ether in the second step. Curing temperatures above 100°C are required for this step-by-step reaction. In return, this system allows a processing time of up to several weeks. Further advantages of this system are low reaction shrinkage, the possibility of casting large volumes without loss of reaction control and good processability. This hardener system allows one- or two-component formulations.
Catalytic curing
One way of curing epoxy resins is polymerization using catalysts
Like anhydride curing, catalytic curing takes place at temperatures above 100°C. Here, hydroxyl groups present in the diglycidyl ether can react with the epoxy ring of another molecule. Tertiary amines or imidazoles, for example, can be used as catalysts. These systems are characterized by a long use duration and very high glass transition temperatures of up to 180°C can be achieved. These formulations are possible in both one- and two-component formulations.
A good example of this is our EPOXONIC 361