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Updated: Jun 28, 2026

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Theoretical considerations in the zone melting of organic substances Analysis of the diffusion gradient
R Friedenberg1, P J Jannke, W Hilding
1School of Pharmacy, State University of New York at Buffalo Buffalo, New York, U.S.A.
Abstract:
Further evidence is gathered in the theory of the zone melting of organic compounds under ideal equilibrium conditions by a kinetic study of the diffusion gradient in the melt zone. A mathematical analysis is developed for the concentration distribution of impurities in the moving molten zone, which yields an expression for the concentration gradient at the liquid-solid recrystallisation interface. These expressions describe the transport process and a measure of the rate of segregation of impurity at the recrystallisation interface. In addition, these equations have been programmed on a computer and concentration profiles for two zone velocities have been graphed. It has been found that the concentration gradient is independent of the length of the zone under ideal equilibrium conditions for pure diffusion.
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