Ultraviolet (UV) radiation primarily affects the outer skins and exposed edges of sandwich panels, but long-term UV degradation can indirectly impact the foam core as well.
If the protective face sheets are damaged or poorly sealed:
- Moisture ingress increases
- Thermal aging accelerates
- Adhesive degradation occurs
PVC foam generally exhibits better environmental durability than XPS under prolonged exposure. PET foam also maintains stable properties under moderate environmental aging.
XPS is particularly sensitive to UV exposure when directly exposed, often turning brittle and discolored over time.
To improve UV resistance, manufacturers commonly apply:
- Gel coats
- PVDF coatings
- UV-resistant films
- Protective laminates
Proper sealing of edges and joints is equally important to prevent water penetration and thermal cycling damage.
