Biodegradable carriers synthesized from ricinoleic acid oligoesters and aliphatic molecules having at least one carboxylic acid and at least one hydroxy or carboxylic acid group that are liquids or pastes at temperatures below 370C and methods of making and using thereof are described herein. The polymers described herein significantly increase their viscosity upon immersion in aqueous medium. These polymers can be used as hydrophobic biomedical sealants, temporary barriers to prevent adhesions, such as organ to organ adhesion, cell supports, carriers for drug delivery, and coatings on implantable medical devices, such as stents. The polymers made from ricinoleic acid oligoesters are less viscous and easier to inject compared to polymers of similar composition and molecular weight prepared from ricinoleic acid monomers, possess a higher molecular weight, retain an incorporated drug for longer periods, and degrade into soft degradation products at a slower rate compared with polymers synthesized from ricinoleic acid monomers. Pharmaceutically active agents can be incorporated into the liquid or pastes without the use of organic solvents.
