b'TECHNICAL & RESEARCHshelf life and application temperature. The MRCA T&Rincluded preparing specimens at nominal laboratory committee members identified two manufacturers, whoconditions (70F) followed by curing at 70F, 85F, will remain anonymous, of cartridge dispensed, low- or 35F in a conditioned environmental chamber rise foam adhesive product to use for the testing. Forfor four and seven-day periods. A separate group testing purposes, WJE identified the manufacturersof puck specimens was prepared within a walk-in as Manufacturer A and Manufacturer B. These twofreezer at 35F and subsequently cured at 35F to manufacturers were selected primarily based onobserve the effect of applying and curing at cold availability of inventory in the possession of MRCAtemperatures.contractor members. The products used in the testing were categorized into two groups in relation to their manufactured on and expiration dates printed on thecartridges:BeforeExpiration(BE)and After Expiration (AE). The shelf-life of the adhesive for both manufacturers is 12 months. The testing regimen identified by WJE included physical testing, material characterization, and chemical testing. Key Highlights of the Test Program Scope Specimen Fabrication. Two primary specimen types were created for physical and chemical testing:3-inchdiameteraluminumpuck specimens(Figure 1) and 8-inch square glassFigure 2. Glass plate specimen, 8x8 inches.plate specimens (Figure2).Puckspecimens were fabricated for use in the SATEC machine to perform tension testing. Glass plate specimens were fabricated to allow for viewing, examining, andchemicallyanalyzingthespreadandcell structure of the foam adhesive. Custom frames were developed to support and position pairs of 3-inch diameter cylindrical aluminum pucks precisely 1/4 inch apart to be utilized for the strength testing portion of the research program. The 1/4-inch separation was selected as being representative of a common thickness for low-rise foam adhesive ribbons used to adhere insulation-to-roof decks and insulation-to-insulation substrates. The protocol Figure 3.SATEC Universal Test Machine Direct Tension Testing. Direct tension testing for all specimens was performed at room temperature (~70F) using a SATEC Universal Test Machine (SATEC) (Figure 3). The SATEC Universal Testing Machineisastaticservo-hydraulicuniversal testing machine with the ability to exert up to 120,000 pounds of force for both tensile strength and compressive strength testing. The testing is performed in a static manner, meaning that the load is applied at a constant rate, 0.05 inches per minute, until failure. The machine measures and records the applied load and displacement from the initial load application to failure, for each specimen.Figure1.Customsteelframewithtwosetsofsixaluminumpuck specimens, 3-inch diameter.Continued on page 8www.mrca.orgMidwest Roofer 7'