What controls the Young's modulus in the glassy regime of an amorphous polymer?

Sliding between short segments of polymer chains

Stretching of molecular bonds

Melting of secondary bands, and an increase in free volume

Second derivative of the energy-separation curve, E∝d2Udϵ2

Changes in entropy associated with changes in molecular configuration, E=−TΩd2Sdϵ2=3nvkbT

1 answer

E= 3nkvbT

given in lectures