The optimization of photoinitiation system for holography by receiving the protection from dithiothreitol

•The structures of 11 thiols showed important effects on the diffraction efficiency, with a maximum value of 98.37%.•The poor performance demonstrated that the dimerization of thiols would lead to a drop in diffraction efficiency.•Dithiothreitol (DTT) was selectively introduced into the PS from several reducing agents.•The presence of DTT enhanced the efficiency of PS and significantly increases the validity period of the photopolymer.•DTT was shown to protect thiols from oxidation to disulfides and from the static quenching occurring with BDEA.