Performance of Tape-Bonded Seams of EPDM Membranes: Effect of Material andApplication Factors on Peel Creep-Rupture Response

摘要

An investigation, conducted under the auspices of an industry-governmentconsortium, studied the effects of material and application factors on the peel creep-rupture response and peel strength of EPDM (ethylen-propylene-diene terpolymer) taped-bonded seam specimens. Two material factors (tape system and thickness) and five application factors (EPDM surface condition, primer, application temperature, application pressure, and time-at-application-temperature) were examined in a two-level statistically designed experiment. Some tapes had thicknesses typical of those commercially available at the time of the study, and were designated as having 'standard' thickness. The thicknesses of 'standard' and thin tapes were approximately 0.9 mm (0.035 in) and 0.6 mm (0.025 in), respectively. Specimens were prepared either primed or unprimed using EPDM that was either cleaned or contaminated. Application temperatures were low, 5 degrees C (41 degrees F), or high, 60 degrees C (140 degrees F), and application pressures were low, 0.2 MPa (30 lbf/square inch), or high, 2 MPa (300 lbf/square inch). The time at which the specimens remained at the application temperature was short, about 24 hours, or long, 672-960 hours. To interpet the data, plots of mean time-to-failure and mean peel strength versus the conbinations of application factors for each of the four pairs of tape system and tape thickness were analyzed. Comparisons of times-to-failure between the tape-bonded sample sets were made with those of liquid-adhesive-bonded sample sets tested in an earlier phase of the study.