  We combine computer simulations and scaling arguments to develop a unified
view of polymer entanglement based on the primitive path analysis (PPA) of the
microscopic topological state. Our results agree with experimentally measured
plateau moduli for three different polymer classes over a wide rangeof reduced
polymer densities: (i) semi-dilute theta solutions of synthetic polymers, (ii)
the corresponding dense melts above the glass transition or crystallization
temperature, and (iii) solutions of semi-flexible (bio)polymers such as f-actin
or suspensions of rodlike viruses. Together these systems cover the entire
range from loosely to tightly entangled polymers. In particular, we argue that
the primitive path analysis renormalizes a loosely to a tightly entangled
system and provide a new explanation of the successful Lin-Noolandi packing
conjecture for polymer melts.
