Inherently radiopaque side-chain crystallizable polymers (IRSCCP' s) are useful in various medical applications. An example of a IRSCCP is a polymer that comprises a main chain, a plurality of crystallizable side chains, and a plurality of heavy atoms attached to the polymer, the heavy atoms being present in an amount that is effective to render the polymer radiopaque. A polymeric material that includes a IRSCCP may be fabricated into a medical device useful for at least partially occluding a body cavity. For example, such a medical device may be an embolotherapy product.