Accelerated Life Testing Models for an Acrylic-Based Pressure Sensitive Adhesives in Consumer Electronics Applications  
Author Victoria C. Robles

 
Co-Author(s) Swanand Vaidya

 
Abstract Acrylic-based pressure sensitive adhesives (PSAs) are widely used in consumer electronics. It is not uncommon for PSAs to exhibit adhesive failures in high temperature and humidity system-level reliability testing. As Reliability Engineers, such PSA failures introduce a unique challenge to determine the equivalent life in the field, because accelerated life models for PSAs are widely undocumented. Assuming the primary adhesive failure mode of PSAs is driven by a chemical reaction, we empirically fit adhesive degradation over time in high temperature and high humidity to an Arrhenius-based accelerated life model and to an Erying-based Temperature-Humidity accelerated life model. Our test samples consist of a modified acrylic double-sided foam-core PSA adhered to a PC-ABS VDI 24 plaque with the liner of the PSA removed and replaced with 0.025mm thick polyester film. The samples dwell for variable times in various combinations of temperatures (40ºC, 60ºC, 85ºC, 105ºC, 120ºC) and relative humidities (1%, 50%, 85%). The sample’s adhesive strength is measured in accordance to ASTM D3330 90º peel test using an Instron. The results are analyzed using an Arrhenius-Weibull model and Temperature-Humidity-Weibull model within ReliaSoft’s ALTA Pro TM software. The activation energies are estimated as well as the acceleration factors for each model.

 
Keywords pressure sensitive adhesives, PSAs, accelerated life testing
   
    Article #:  RQD25-190
 
Proceedings of 25th ISSAT International Conference on Reliability & Quality in Design
August 1-3, 2019 - Las Vegas, NV, U.S.A.