Sérgio Mascarenhas de Oliveira (born May 2, 1928) is a noted Brazilian experimental physicist, educator and scientific leader.
He has been awarded several prizes including the Brazilian Order of Scientific Merit in the categories of Commander and Great Cross, the Conrado Wessel Prize for General Science, the Joaquim da Costa Ribeiro Prize and the Guggenheim Fellowship.
His main contributions to science are new observations of the thermo-dielectric effect; the discovery of bioelectrets, i.e.
electrets as a property of biological materials such as bone and biopolymers, enabling the development of a new detector used in radiological dosimetry to date human bones in archeological sites; and the development of a non-invasive procedure to measure intracranial pressure.
Mascarenhas has contributed to the creation of important Brazilian research institutions, such as the farming instrumentation center of the Brazilian Agricultural Research Corporation and the Federal University of São Carlos.