Chain Entanglement in Polymer Melts and Solutions

We consider the problem of entanglement in polymer melts and solutions with no excluded-volume interactions (esolvent). A number of simple ideas on this subject, cast in the form of scaling theories, have recently been proposedintheliterature. Atfirstglancetheseideasare seeminglyunrelated. Firstweshowtherelationbetween the various scaling pictures of polymer entanglement. In sodoing,wewilldevelopaclearerpictureoftheunderlying physicsassociatedwitheachidea. Wewillshowthatthe differences between the scaling ideas arise because there are two independent length scales in the problem, which means that scaling must rely on a conjecture about the natureofentanglement. Wethenexamineexperimental data on polymer melts and solutions to test these ideas.