Glassy conformations in wrinkled membranes

Partially polymerized membranes display a striking mechanical transition at low temperature known as the wrinkling transition. Fluorescence and scanning electron microscopy as well as profile measurements using an atomic force microscope revealed the existence of three degrees of wrinkling depending on the degree of the membrane polymerization. At low polymerization the membrane undergoes a cascade of wrinkling to form a folded phase with a characteristic exponent η equal to 3, at intermediate polymerization, the membrane is in an intermediate-wrinkled phase (similar to the crumpling of an elastic sheet) with η∼2.5, while at high polymerization the membrane undergoes an abrupt "compaction" to the wrinkled-rough phase with η∼2.