Surface Protection
UV light degrades thermoplastics, including polycarbonates: decline of mechanical properties, for example, impact resistance, is indicated by yellowing of the sheet. To prevent deterioration Marlon CS Longlife has a UV protective layer co-extruded on to the outer surface, forming a barrier against UV light entering the body of the sheet, minimising long term yellowing and ensuring durability and toughness.


Impact Resistance.
Of all glazing materials polycarbonate exhibits greatest resistance to impact over a temperature range of -40 to +130°C. It is approximately 200 times more resistant to impact than glass; PVC has limited impact resistance at low temperatures; GRP sheet is resistant to impact but will show impact abrasions much more easily than polycarbonate.

High impact resistance means that Marlon CS Longlife is suitable for use in areas where hail storms would cause excessive damage to other glazing materials. FALLING DART IMPACT TEST The impact test illustrated demonstrates the impact resistance of Marlon CS Longlife. A striker of diameter 16mm contacts a sample of sheet placed on a support ring with inner diameter 38mm. A weight of 1.8kg is dropped on to the striker from a height of 1.5m. The resulting impact energy of 27Nm only dents the sample: it does not crack or penetrate.

Weatherability
Accelerated weathering tests in a weatherometer produce little change in light transmission or yellowness index. Significantly, accelerated and natural weathering have negligible influence on the physical properties of Marlon CS Longlife, eg tensile strength, impact resistance.
During the life of the sheet natural weathering will leave its thermal or mechanical properties essentially unaltered.

The protected surface is always clearly identified. The sheet must always be fitted with the UV protected side out, otherwise it will deteriorate, as will be shown by yellowing and decline of physical properties, e.g. the sheet will become brittle and lose impact resistance.