Abstract
The unperturbed chain dimensions of near-monodisperse atactic polystyrenes were evaluated from intrinsic viscosity measurements in 12 different solvents under θ or near-θ conditions over the temperature range 8.5-75.0 °C. In consonance with the indications of other workers, larger values of unperturbed dimensions were found in cyclic hydrocarbon solvents than in other ideal solvents at similar temperatures. Negative values for the temperature coefficient of chain dimensions were found within the three solvent series examined. Under conditions where specific solvent effects are eliminated or minimized, measurements yielded results in excellent agreement with the theoretical predictions for atactic polystyrene, i.e., d In (r2)0/dt = -1.1 X 10-3 deg-1. © 1985, American Chemical Society. All rights reserved.