Theory 28/Solvation & interfaces/Foams
Foam Life Is Elasticity Against Drainage
The claim
Foam persistence is set by the ratio of surface elasticity to drainage rate, so a film that resists stretching lasts while a rigid one drains and ruptures.
01Mechanism
Films thin by gravity and capillary suction; elasticity resists local thinning.
02Prediction
Lifetime should track the ratio.
03Refutation
Lifetime tracking viscosity would remove elasticity.