The ten classes of polymeric phase transitions: their use as models for self-assembly

A brief overview of the ten classes of polymer phase transitions is given. In each case the basic physics underlying the transition is given. Special attention is devoted to the polymer threading a membrane transition (PTM) since it allows us to understand the reason for the occurrence of the five classes of transition unique to the isolated polymer molecule. They are the PTM transition; the helix to random coil transition; adsorption; equilibrium polymerization/one-dimensional crystallization; the collapse transition. The five classes of transitions of interacting polymers are liquid crystals/plastic crystals; glasses; crystals; liquid-liquid polymer transitions; soaps-block copolymers/membranes-micelles-vesicles. A classification is made of the coupling of these transitions to one another in pairs, triplets, etc, and it is observed that the number of kinds of such transitions is in the thousands. Because of the five transitions unique to polymers it is argued that the class of materials richest in the occurrence of phase transitions are polymers. Self-assembly is viewed essentially as materials undergoing phase transitions. It is evident that of all materials, polymers express self-assembly in fullest measure. A classification scheme is given for self-assembled structures both in biology and as a technology opportunity. The paradigm developed in this paper enriches polymer science by revealing the existence of a large number of problems awaiting solution. This paradigm also provides a route towards understanding biological self-assembly. (C) 1999 Elsevier Science Ltd. All rights reserved.