A range of new materials can be obtained by the cationic, free radical, or thermal copolymerization of natural and modified oils with a number of petroleum-based comonomers. These novel new biobased materials possess good thermal stabilities, good mechanical properties, and good damping and shape memory properties. Unique new bioplastics have also been prepared by the ring opening metathesis polymerization (ROMP) of modified oils and fatty alcohols in the presence of strained cyclic alkenes to form rubbery to hard materials. In order to improve the performance of these new bioplastics, inorganic fillers and natural fibers have been used to reinforce the cationic, free radical, and ROMP resins. Vegetable oil-based waterborne polyurethane dispersions (PUD's) have also been synthesized from vegetable oil polyols. In order to improve their properties, the PUD's have been copolymerized with an emulsion of vinyl or acrylic comonomers to form a series of polyurethane/acrylic hybrid latexes. Core-shell latexes have also been obtained by the emulsion copolymerization of PUD's with vinyl comonomers. All of these materials exhibit properties similar to or better than related petroleum-based products.