For rigid photovoltaic (PV) cell encapsulation, durable adhesion of the polymeric encapsulant to glass is one of the most
important considerations in developing a reliable PV module. The great challenge for encapsulant materials is to obtain
adhesion that survives humidity stress at high temperature, since all organic polymers are to some degree permeable to
water vapor and water molecules can migrate to the interface and degrade the adhesion. Several test methods were used
to accelerate the adhesion degradation process for materials screening. Solar grade EVA and several experimental
encapsulant materials were used for the study, which included a detailed analysis of the combined role of moisture and
temperature in inducing loss of adhesion. The effect of moisture and temperature on adhesion mechanisms and polymer
properties will be discussed.