METASTABLE GLOBULES IN GOOD SOLVENTS - TOPOLOGICALLY STABILIZED STATEOF POLYMERS

A novel state of polymers in solution is proposed. It is suggested tha t macromolecules which are initially collapsed in a poor solvent maint ain a long-lived, partially collapsed conformation upon a fast tempera ture jump into the good-solvent regime. This metastable state is stabi lized by topological constraints, i.e. tight intra-molecular knots. Th e number of tight knots and the tensile forces which generate them are related to experimentally observable quantities such as the radius of gyration and the relaxation time of the partially swollen globule. An experimental test of the theoretical prediction is proposed, includin g an analysis of the role of control parameters such as degree of poly merization, chain flexibility and the depth and kinetics of the temper ature quenches.