A phase change material (PCM) composition comprises a blend of at least one fatty acid ester and at least one ethylene copolymer, wherein the ethylene copolymer comprises at least 28% of an at least one polar comonomer by weight, based on the weight of the ethylene copolymer. A film or sheet comprises or is produced from the PCM composition and the film or sheet can be a single layer or multilayer structure.
