Low temperature tensile lap-shear testing of adhesively bonded polyethylene pipe

This work studies the lap-shear strength performance of polyethylene pipeline bonded with acrylic adhesive in the temperature range -10 to +20 degrees C. Single lap shear test samples were firstly prepared at 20 degrees C under various clamping pressures and curing times to determine suitable conditions under which to prepare and test further samples at temperatures of -10,-5, 0, +5 and +20 degrees C. It was found that a decrease in curing/testing temperature to Zero degrees resulted in a steady reduction in the lap-shear strength performance of the bonded joints from a mean value of 2.72 MPa at +20 degrees C to 1.15 MPa at 0 degrees C. Below zero degrees the strength of the bonded substrates was significantly reduced; no samples bonded at -5 degrees C had sufficient strength to test and only one sample bonded -10 degrees C was tested, which had very low strength of 0.105 MPa.