C. G. Overberger

THE USE OF PHYSICAL METHODS TO DETERMINE POLYMER CONFORMATION IN SOLUTION

ABSTRACT Of the physical methods used to determine polymer conformations in solution, we present three. The first combines optical rotatory dispersion and circular dichroism, viscosity, dipole moments, and semiempirical conformational energy calculations which we have used with asymmetric polyamides in solution. The second examines conformational changes in the mutarotation of poly(trans-5-methyl-L-proline) by determining the kinetics of the mutarotation using optical rotatory dispersion, circular dichroism, ultraviolet and infrared spectroscopy. Lastly, the conformation of a macromolecule in solution can be studied by kinetic methods. If the macromolecule contains catalytic functions, their reactivity towards a particular substrate will frequently depend on the spatial arrangement of the groups along the polymer chain. We have studied the rate of hydrolysis of poly-4 (5)-vinylimidazole in water-alcohol solutions on substituted substrates and have found we can associate these changes in the rate of hydrolysis partly with conformational changes.