Phase I research demonstrated the feasibility of preparing biopolymer supported phase change materials to store useful quantities of energy. By chemical modification of clothing-type polymers with phase change materials, it was shown that the derivatized products can reversibly store significant quantities of energy as heat. The products were found to release the heat energy at temperatures that are attractive for a clothing application. It was found that the temperature of transition could be adjusted as desired. The Phase II program continues and expands upon this research study. The proposed work includes a detailed study of the polymer functionalization reactions and a determination of the scope of the latent heat capabilities of the products. Extension of the chemistry to fibers and synthetic polymers is also planned.