Journal of Adhesion, Vol.96, No.11, 1003-1026, 2020
Effect Of Accelerated Ageing Cycles On The Physical And Mechanical Properties Of A Reversible Thermoplastic Adhesive
In this work, a polyolefin thermoplastic adhesive has been modified with three different weight percentages, 3%, 5% and 10% of iron oxide powder. The use of this nano-modified adhesive coupled with this technology, offers an improved resistance to applied loads, new opportunities connected with the bonding process and the possibilities to dismantle plastic components for reusing, repairing or recycling at the end of life. In this research activity, the mechanical properties of the pristine and modified adhesive have been assessed. Furthermore, the effect of three different accelerated ageing cycles, currently used by automotive industries, have been studied in relation to the mechanical behaviour and separation time. Three ageing cycles were evaluated that are: hot, humid and mixed cycles. Single Lap Joint tests prove the variations of the mechanical properties and adhesion strength during the accelerated ageing, especially for the hot cycle. Fourier Transform Infrared Spectroscopy has been used and shows that the adhesives exposed to the hottest ageing cycle presented a high value of the oxidation that leads to a partial detachment of the adhesive from the plastic substrates. Joint separations by means of an induction heating system showed that adhesive joints can be separated before and after ageing cycles.