The group of “special anhydrides” includes, amongst others:
- Hexahydrophthalic anhydride – HHPA
- Tetrahydrophthalic anhydride – THPA
- Methyltetrahydrophthalic anhydride – MTHPA
- Methylhexahydrophthalic anhydride – MHHPA
- Nadic anhydride – NAN
- Methyl nadic anhydride – m-NAN
These anhydrides are primarily used as hardeners in epoxy resin formulations as well as cross-linkers in polyester resin systems. The various anhydrides or their mixes are used depending on the requirements of the end product.
THPA is predominantly utilized as a hardener for epoxy resins and as a “building block” for polyester and alkyd resins.
HHPA is also used as a hardener for epoxy resins as well as an intermediate product for (unsaturated) polyester and alkyd resins. The high colour stability in comparison to other anhydrides is particularly worth highlighting here.
HHPA is especially suited for applications where high load epoxy systems are required due to its very low viscosity and high mixture ratio with epoxy resin.
MTHPA is used almost solely as an epoxy hardener but is also compatible with many other resin systems. It forms a stable, low viscosity mixture with the base resin which allows for long processing times. It is particularly suitable for applications in the fields of casting, impregnation and laminate resins. By using MTHPA it is possible to achieve excellent qualities in electrical insulation, which is why it has a broad range of uses in transformers, electronic resistors and circuits as well as countless other similarly embedded uses.
MTHPA is also superbly suited for use as a hardener in fibre-reinforced plastics and laminates due to its excellent wetting properties. Important fields of application are wind turbines, piping, sports equipment, composites and many more.
MHHPA is a hardener for epoxy resins and is also utilized as a building block for polyester resins. The product boasts first class optical properties with high UV resistance due to its
cycloaliphatic structure. In addition to this, the use of MHHPA significantly enhances the end product’s mechanical, electronic and chemical resistance. MHHPA is therefore used for electronic high performance applications like LED or OLED for example. MHHPA’s first class colour properties justify its utilization in polyester resins for clear varnishes for the automotive industry and other sectors.
NAN and m-NAN are both – as described above for the previous products – used as hardeners in epoxy resins. m-NAN is compatible with many resin systems and forms, similarly to MTHPA, a stable, low viscosity mixture with the base resin which allows for long processing times. m-NAN’s unique bicyclic structure results in an excellent resistance to heat as well as outstanding electronic properties in the end product which achieves a noticeably higher Tg.
All anhydrides are also available as mixtures – even custom-made.
HHPA, MHHPA, MTHPA and m-NAN are available in 220 kg drums, IBCs up to 1000 kg or in bulk truck loads. THPA is packed in sacks of 25 kg and big bags with a net weight of 500 kg. We stock NAN in 25 kg sacks or drums.