The descriptions for the Electronic Supplementary Information files are as follows.

sup_info.pdf : main supplemental file containing figures, captions, and descriptions of supplemental materials.

unentangled.avi : movie of an initially unentangled molecule stretching in an  elongational field of De=2. The movie is in real time with a frame rate of 30 fps.

selfentangled.avi : movie of an initially self-entangled molecule stretching in an elongational field of De=2. The movie is in real time with a frame rate of 30 fps.