STP1349

    Evaluation of In-Service Thermoplastic Olefin (TPO) Roofing Membranes

    Published: Jan 1999


      Format Pages Price  
    PDF Version (532K) 24 $25   ADD TO CART
    Complete Source PDF (4.2M) 24 $55   ADD TO CART


    Abstract

    As part of a five-year investigation, mechanical (strength and elongation) and chemical (thermogravimetry and dynamic mechanical analysis) methods of evaluation are used in this paper to characterize in-service thermoplastic olefin (TPO) roof membranes. All the non-reinforced membranes meet the minimum thickness and tensile strength requirement as specified in the proposed ASTM standard. The polyester scrim reinforced membranes had higher tensile strength and elongation values than those reinforced with random mat of short glass fibers. The standard should consider defining the breaking strength in terms of “stress” instead of load and incorporating strain energy requirements at 23 °C and -40 °C. The term TPO is confusing and very vague and the standard should consider differentiating between the different types of TPOs. Based on thermogravimetry, at least four different types of TPOs are currently in service. Lastly, the standard should consider using the glass transition temperature to monitor changes in membranes due to aging/weathering.

    Keywords:

    roofing membrane, single-ply roofing, thermoplastic olefin, thermoplastic polyolefin, TPO, polyethylene, polypropylene, flexible polyolefin, FPO, flexible polyolefin alloy, FPA, FPO-A, glass-transition temperature, Tg, dynamic mechanical analysis, DMA, thermal analysis, thermogravimetry


    Author Information:

    Simmons, TR
    Benchmark Inc., Cedar Rapids, Iowa

    Paroli, RM
    Institute for Research in Construction, National Research Council of Canada, Ottawa, ON

    Liu, KKY
    Institute for Research in Construction, National Research Council of Canada, Ottawa, ON

    Delgado, AH
    Institute for Research in Construction, National Research Council of Canada, Ottawa, ON

    Irwin, JD
    Institute for Research in Construction, National Research Council of Canada, Ottawa, ON


    Paper ID: STP13296S

    Committee/Subcommittee: D08.20

    DOI: 10.1520/STP13296S


    CrossRef ASTM International is a member of CrossRef.