The connection between these predictions and experimental systems remains sparse in the literature, but qualitative trends from both experiments and computer simulations suggest that the overall size and persistence length of bottlebrushes does increase due to the presence of side chains. In particular, both SANS and light scattering and viscosity have shown evidence that p can increase by an order of magnitude as the length of side chains increases. In case of molecules with dendronized side chains (upto third generation), light scattering studies have shown a modest increase in p ; the overall conformation appearing more like a semiflexible chain rather than a rigid rod. There are challenges associated with extracting a "true" persistence length that does not change with the overall length of the chain, as evidenced by extensive molecular simulations. However, the wormlike cylinder model appears to work quite well in extracting a persistence length from experimental data, and indeed show a pronounced effect of side-chains. Nevertheless, there are experimental results that show instead that the p remains essentially unchanged despite significant increase in N sc . The large volume of experimental and theoretical work remains rife with conflicting ob-servations. Many of these issues have been discussed at length in a recent review by Binder et al. This is in part due to the idealization required to make progress with theory, which is compounded by the reliance on experimental characterization that does not directly image the bottlebrush chains but instead infers structure from model predictions. Furthermore, efforts to include simulation data have often used similarlyidealized molecular models, that rarely invoke the specific chemistry used in a given bottlebrush in favor of universal statements.