What adhesion and flexibility criteria must roof sealers meet under thermal cycling?

Roof emulsions must maintain adhesion after repeated hot and cold cycles, UV exposure, and wet aging without cracking, peeling, blistering, or loss of film continuity. Practical criteria include crack-bridging ability at defined temperatures, elongation or elastic recovery of the cured residue, adhesion retention after heat and water immersion conditioning, and resistance to ponding water where required. Systems are also judged by minimum dry film thickness and reinforcement compatibility, because seams and transitions move most under thermal cycling. Cure profile must prevent trapped moisture that causes blisters.