Dow’s portfolio of materials for roofing membranes features advanced polymers for thermoplastic polyolefin (TPO) systems. These proven, highly respected solutions can help manufacturers develop custom-tailored formulations that fit specific designs, production processes, and end-use requirements. With several advantages over incumbent materials, ENGAGE TR Polyolefin Elastomers (POEs) represent the company’s current state-of-the-art for TPO-based membrane formulations. According to the manufacturer, ENGAGE TR POEs offer an ethylene-based solution that has inherently better longevity, and can be formulated to produce membranes with significantly improved flexibility and broad welding window. The unique design of ENGAGE TR also allows increased filler loading, which can, in turn, be used to improve fire performance.
According to the manufacturer, in a comparison of formulations based on a typical polypropylene (PP) TPO and ENGAGE TR, the Dow material offers:
- 40 percent lower modulus for increased flexibility and ease of installation
- Reduced glass transition temperature (Tg) for better low temperature toughness
- Excellent thermal stability which can help deliver better property retention over time
Membranes formulated with ENGAGE TR POE offer increased weatherability/UV resistance, according to the company. Scanning electron microscope (SEM) photography taken after 10,000 hours of accelerated weathering reveals surface cracking in the PP TPO-based membrane. In sharp contrast, the ENGAGE TR POE-based membrane remains crack free at the same stabilizer package. This indicates higher levels of UV and weather resistance, which correlate to longer service life. Better UV resistance is expected for a polyethylene based chemistry thanks to the lack of tertiary carbon which is intrinsic to PP and prone to chain scission.
According to the company, whether you’re working with TPO-, PVC- or EPDM-based systems, Dow’s roofing membrane science can offer:
- Flexibility that lasts, even in thicker sheet installations
- Long-term durability
- Weatherability/UV resistance that meets or exceeds appropriate industrial standards
- Fire performance with halogen-free, low-smoke, low-ignitability, and low-fuel load options
- Light color/cool roof formulations to reduce heat absorption
- Multiple attachment options, including fully adhered, heat welded, mechanical, and/or ballasted systems
For more information, visit www.dow.com.