In this paper, the second of a series of two presenting the structural effects on the dynamic properties of complex liquids, we discuss the effect of structural changes in the alkyl side chain on the macroscopic viscosity and microscopic motional behavior of phthalates. C-13 NMR spin-lattice relaxation times and nuclear Overhauser enhancements of individual carbon nuclei of di-n-octyl phthalate (DNOP), di-n-hexyl phthalate (DHP), and bis(6-methylheptyl) phthalate (DIOP) have been measured as a function of temperature from -40 to 70 degrees C. Individual C-13 peaks were unambiguously assigned by using 2D H-1-C-13 chemical shift correlation and specific relaxation of individual carbons in the alkyl chain of the molecule. In addition, the density and viscosity of these compounds as a function of temperature have been measured. The results were also compared with earlier experiments performed on bis(2-ethylhexyl) phthalate (DEHP). The optimized parameters of the Cole-Davidson distribution model obtained from the analysis of the C-13 relaxation data provided the detailed information on the internal motions of the alkyl side chains. The NMR relaxation data and shear viscosity of the phthalate liquids were interpreted phenomenologically in terms of the alkyl side chain flexibility. The branching in the alkyl chain restricted the motional degree of freedom of the side chain, which made the molecule less flexible as a whole. The branching near the rigid part of the molecule was found to be more effective in restricting the internal motion of the alkyl chain.