Thermochemistry of the binary system nitrocellulose + dimethyl 4,4´-dinitroheptanedioate

Abstract

The DSC measurements of the binary mixtures of nitrocellulose (NC) and dimethyl 4,4´-dinitroheptanedioate (DNHD), of expected fine plasticizing properties, were carried out. It was concluded that depending on the time interval between measurements, in cases of specifically low DNHD content in NC mixtures DNHD did not crystallize. The course of the melting process during the second and subsequent measurements performed on the same sample indicates that the process was taking place in confined spaces, i.e. pores as well as in unconfined space. The occurrence of two i.e. high-temperature and low-temperature glass transitions as well as β-relaxation was observed, depending on the composition of the samples and time interval between the measurements. The thermochemical properties of the investigated DNHD/NC binary system are complex and allow to conclude that thermal behavior of the samples across a variety of concentration and temperature ranges, reflects limited miscibility of the components used.