The invention describes methods of preparation and compositions of plasticizers. The plasticizers include at least 2 alkyl ketal ester moieties and have a molecular weight of greater than 300. In one aspect, the alkyl ketal ester moieties are levulinic ester ketals. Certain compositions contain at least one of an antioxidant, a UV stabilizer, a thermal stabilizer or mixtures thereof, present in the composition from about 0.01 to about 5.0 percent by weight of the total composition.