What exactly is Expanded Polystyrene (EPS)?
It is a lightweight cellular material consisting of fine spherical shaped particles, which are comprised of 98% air and 2% polystyrene. This air is trapped within a number of closed hollow cells in each particle. PolyDeck® is made from EPS.
Does PolyDeck® absorb water?
EPS is a closed cell and cannot absorb water. During the process of moulding a block, tiny channels are formed between the EPS particles. If the material is immersed in water these tiny channels can be filled with water. After immersion for more than 360 days, there may be up to 6% water content by volume, which has entered the channels.
Even under such an adverse and rare condition of prolonged saturation, EPS suffers little adverse effect. It maintains its shape, size, structure, cohesion and physical appearance. The ability of EPS to resist the adverse effects of moisture is exemplified by its widespread use in floats, marinas and other applications, which involve full or partial submergence in water for prolonged periods of time.
Is PolyDeck® strong?
Yes. EPS is manufactured in a number of classes (or densities), and each class exhibits excellent compressive and flexural strength and dimensional stability characteristics ...at a very high strength to weight ratio.
The range of classes available enables specifiers to select the most appropriate balance between structural and insulation properties for any building application.
Is PolyDeck® resistant to chemicals?
It depends. It is resistant to virtually all aqueous media including dilute acids and alkalis and to methanol, ethanol and silicone oils.
It has limited resistance to paraffin oil, vegetable oils, diesel fuel and Vaseline, which may attack the surface of EPS after long-term contact.
It is not resistant to hydrocarbons, ketones, esters, paints containing thinners, and solutions of synthetic adhesives.
Is PolyDeck® degraded by ultraviolet light?
Prolonged exposure to sunlight will cause a slight discolouration (yellowing) of EPS insulation and cause some surface embrittlement.
Is PolyDeck® subject to Australian Standards?
Yes. Manufacturers when stating the class of EPS and therefore its physical characteristics are required to manufacture to AS1366 Part 3 - 1992.