Weatherability of coated fabrics as roofing material in tropical environment

The weatherability of PTFE- and PVC-coated fabrics under tropical climate was evaluated based on outdoor exposure test for a period of 2 years. This study is confined to the examination of the surface characteristics of 10 different types of fabric which include dirt repellency, discolouration and coating condition. The results indicate that the dirt repellency of PTFE-coated fabrics is generally more superior. However. the surface treatment for some of the PVC-coated fabrics, do provide excellent dirt repellency as well. Morphological examinations using the scanning electron microscope revealed that cracking and peeling of the coating were more evident on the PVC-coated as compared to the PTFE-coated fabrics. The hot and humid conditions prevalent in a tropical environment were very conducive for the growth of fungi, which adhered on the surface of some of the PVC-coated fabrics. Generally the degree of surface degradation on all the fabrics was more severe due to the much harsher tropical climate in comparison with other exposure tests conducted in the past. (C) 2003 Elsevier Ltd. All rights reserved.