PET/THV for architecture

 

Coated textiles find more and more application in architecture as membranes for tensioned structures.

At the moment PTFE-coated glass fibers or PES-PVC fabrics and ETFE films are predominantly used for this purpose. However, sunlight transmission of these fabrics is limited and their areal weight is substantial. Therefore Van Wees developed a laminate based on an alternative fluoropolymer, namely THV, which has excellent optical properties and thanks to its thermoplastic nature can be welded to the dimensions which are common in architecture. For weight reduction polyester instead of glass yarn has been chosen as reinforcement, which is visible as an open web in the THV-laminate. Of course, the orientation of the yarns can be varied to optimize the mechanical properties in the critical directions: for instance three yarn layers in a -60/0/60° geometry (triangular) or four in a -45/0/45/90° one (diagonal). This simultaneously contributes to the aesthetic appearance, which can be even more enhanced by using attractive dyes in the impregnation treatment of the yarns. In this manner laminates can be produced with an areal weight of about 500 g/m² and a reinforcement factor of six in tensile- as well as tear strength compared to a THV film.