The role of topological constraints in the kinetics of collapse of macromolecules
نویسندگان
چکیده
2014 It is shown that the kinetics of collapse of a polymer coil consisting of N segments after an abrupt decrease of temperature is a two-stage process if N ~ Ne. The first stage takes a time ~ N2 and leads to the peculiar state 2014 crumpled, or fractal, globule. Any part of a chain of any scale is itself a globule in this state ; these parts are segregated from each other in space due to the non-phantomness of a chain. The chain fold in the crumpled globule is a fractal line with fractal dimension 3, equal to the space dimension. The second stage is a chain knotting ; it is realized by means of reptation-like mechanism of motion, takes a time ~ N3 and is accompanied by an increase of globule density. J. Phys. France 49 (1988) 2095-2100 NOVEMBRE 1988,
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