From the empty bottle
to a genuine foam core!


Polyethylene Terephthalate (PET) foams are the newest structural core materials in the composite industry. The first in the market, Armacell commercially launched ArmaForm PET in 2006. In less than ten years, ArmaForm Core has been able to establish a place among core materials for sandwich structures and is steadily substituting traditional materials such as Balsa, SAN or PVC.

The reason is simple: with outstanding product quality, tremendous diversity of uses and truly sustainable production, ArmaForm Core offers you new perspectives toward your business. It is the change in the core that will change your options, whether you are in wind energy, rail and road transport, marine or building and construction.

Lightweight and high mechanical strength in conjunction with residual flexibility and maximum service life are what you expect of a modern composite material, and that is what you get from us, with a great deal more: 


excellent fatigue properties: The long-term behaviour of sandwich structures is a major concern for dynamically loaded applications. ArmaForm Core foams display a threshold level of >60%.


high temperature resistance: Higher curing temperature means shorter cycle times, increased productivity, better mechanical properties in the laminate and peel strength. At +150°C ArmaForm Core allows a process time of days with full vacuum.     


limited density variation: The mechanical properties are all related directly to the density; even small variations have a big impact. ArmaForm Core's extrusion process keeps density variations rather low, at less than 5%.


process versatility: High-performing core material is of less use if it adds complexity and costs to the manufacturing process. ArmaForm Core is compatible with various production methods like infusion or pre-preg, as well as with all common resin systems.


thermoformability: Due to its thermoplastic nature, ArmaForm Core is well-suited for thermoforming. 3D-shaped or double curved sandwich panels are possible without cutting the foam and thus eliminating core stress concentration and increased resin consumption.


recyclability & sustainability: ArmaForm Core is 100% recyclable after its use phase. Furthermore, it is already 100% made of post-consumer PET and is still recyclable afterwards. You cannot find a more sustainable foam core in the composite industry!

The ArmaForm Core product family comprises two grades, PET GR and PET GFR. Our foams are offered in densities from 65 to 250 kg/m³, in thicknesses from 5 mm to 150 mm. 


PET GR grade - for highly sustainable requirements

The short-cut ‘GR’ stands for 'green', which refers more to the guiding principal than to the foam's colour. A ‘green’ plastic? What sounds like a contradiction in terms is in fact a cutting-edge technology which took the Armacell global R&D team several years to develop: to produce PET foam boards with consistent, reliable qualities, 100% made of post-consumer (recycled) PET material. Our green foam core meets not only stringent technical requirements for composites but also follows the guidelines for circular economy and helps to preserve and enhance the human environment. 

Whereas other PET foam manufactures claim to offer PET foam cores made with recycled PET – perhaps re-using their own material loss by mixing it back into the production process - Armacell is the only manufacturer able to offer PET foams 100% made from PET bottle recyclate. We are proud to say that ArmaForm PET outperforms any other structural foam core in the composite industry in terms of environmental benefits, whether competing PET foam or other polymeric foams like PVC, SAN or PUR. More detailed information is provided in our technical bulletin "Life Cycle Assessment".


PET GFR grade - for stringent FST requirements

With ArmaForm Core GFR grade, we offer a structural foam core designed for but not limited to the transport industry's more stringent flame, smoke and toxicity (FST) requirements. This fire retardant, self-extinguishable version of ArmaForm Core combines superior FST performance with outstanding fatigue resistance and mechanical properties. PET GFR has been certified according to the relevant railway FST standards, including NF F16-101 and DIN 5510-2.

EN 45545-2 certification requires the testing of the final composite sandwich, laminates plus core material. Official testing has proved that in combination with appropriate skins, sandwich structures with ArmaForm Core meet HL3 classification, which qualifies the material for all types of train applications. This is valid for all ArmaForm Core foams, whether our standard PET GR grade or the self-extinguishable PET GFR grade. More information is provided in our technical bulletin "Development of durable train floor compliant with EN 45545-2".