Thermoplastic Polyolefin (TPO)
Thermoplastic Polyolefin (TPO) is a single-ply reflective roofing membrane made from polyprophylene and ethylene-propylene rubber polymerized together. TPO can be installed either fully adhered, mechanically attached, fleece back adhered, or as a self-adhering sheet, with the seams of the roofing system sealed with liquid adhesives or welded together. The first sheet of TPO roofing membrane was installed in 1989 and since then millions of square meters of TPO have been installed worldwide. TPO membranes commonly are white.
TPO membranes are produced by calendaring with lamination, extrusion with lamination, or extrusion-coating techniques. TPO sheets are a blend of polypropylene and ethylene-propylene polymers and usually are reinforced with polyester. TPO sheets contain colorant, flame retardants, UV absorbers, and other proprietary substances to achieve desired physical properties.