A Study to Establish an Evaluation Method for Selecting Suitable Packing Adhesives for A/C Ducts to Ensure Sustained Adhesiveness in Thermal and Condensation Conditions over the Vehicle's Lifetime

<div class="section abstract"><div class="htmlview paragraph">The purpose of air conditioning (AC) duct packing is multifaceted, serving to prevent condensation, eliminate rattle noise, and provide thermal insulation. A critical aspect of duct packing is its adhesive quality, which is essential for maintaining the longevity and effectiveness of the packing's functions. Indeed, the challenge of achieving adequate adhesivity on AC ducting parts is significant due to the harsh operating conditions to which these components are subjected. The high temperatures and presence of condensation within the AC system can severely compromise the adhesive's ability to maintain a strong bond. Moreover, the materials used for these parts, such as HDPE, often have low surface energy, which further hinders the formation of a durable adhesive bond. The failure of the adhesive under these conditions can lead to delamination of the duct packing, which can result in customer inconvenience due to rattling noises, potential electrical failures if condensed water contacts electrical components beneath the ducting, or loss of thermal energy, thereby reducing the AC system's thermal efficiency.</div><div class="htmlview paragraph">This paper primarily focuses on developing an experimental methodology to identify the most appropriate adhesive for use in ducting applications. This involves a detailed examination of various adhesive types and designing suitable experiments to evaluate the adhesive bond's resilience, particularly when applied to HDPE blow-molded ducts. The methodology aims to ascertain the conditions under which the adhesive bond fails, ensuring that the selected adhesive can maintain its integrity under the rigors of operational stress and environmental factors. Additional insights gained from the study highlight the influence of surface roughness, resting time, and exposure to extreme temperatures on the lamination quality of duct packing. These findings are crucial for manufacturers to consider when selecting adhesives for AC duct systems, ensuring that the chosen solutions are robust enough to withstand the demanding conditions of automotive environments and maintain the integrity and functionality of the duct packing over time.</div></div>