where k2 is called the Huggins viscosity constant and is derived from the slope of the plot of reduced viscosity with c. This constant can be understood as a measure of solvent quality. For example, for polymers in a good solvent k2 ≈ 1/3, while in poor solvents k2 values are in the range 0.5 – 1. Details of the values of this constant can be found in the literature [29].