The possibility of producing the ferroelectric state in nanoporous aluminum oxide loaded with triglycine sulfate and Rochelle salt has been studied. Our dielectric, pyroelectric and emission measurements give grounds to suggest that this state persists in the composites under study up to temperatures exceeding the Curie point of bulk crystals by several tens of degrees.

Dielectric relaxation in ferroelectric composite nanocrystalline cellulose – triglycine sulfate in the frequency range from 10³ to 10⁶ Hz in a weak measuring field (1 V·cm⁻¹) from room temperature to the phase transition temperature of these composites (+54°C) has been investigated. Two series of nanocomposites were used: the first one with the perpendicular directions of nanochannels with respect to the sample surface and the second one – with parallel. The typical for single-crystal triglycine sulfate maximum of the imaginary part of dielectric permittivity at frequencies (10⁵ Hz – 10⁶ Hz) in the case of composites nanocrystalline cellulose – triglycine sulfate is shifted to the range of lower frequencies (10⁴ Hz – 10⁵ Hz).

Influence of the humidity on dielectric properties of composites nanocrystalline cellulose – triglycine sulfate in weak measuring field (1 V·cm⁻¹) was investigated from room temperature to +120°C in the frequency range from 10⁻³ to 10³ Hz. A comparative analysis of experimental results before and after heat treatment of samples was made. It was shown that before the heat treatment an additional peak at about +20°C in the temperature dependence of dielectric constant and a low-frequency maximum at 1.6 mHz in the frequency dependence of dielectric loss are observed. They are conditioned by the evaporation of water from the sample surface at the beginning of heating and the near–electrode polarization due to the accumulation of charge carriers at the electrode–composite layer respectively.

This paper is devoted to studies of properties of composites based on nanocrystalline cellulose and triglycine sulfate. The presence of one or two peaks in the temperature dependence of dielectric permittivity was revealed and their shift to higher temperatures as compared with the bulk TGS to 54°C and 100°C was detected, respectively. An explanation of the results is related to the appearance of internal bias fields in the nanocomposites.

Dielectric properties of composites consisting of nanoporous aluminium oxide Al₂O₃ or glass SiO₂ with inclusions of the ferroelectric triglycine sulphate (TGS) are investigated in the present work. Our investigations enable us to assume the presence of ferroelectric state in these materials.