Phosphate and sulfate containing inorganic mixture as thermal retardant: synthesis, characterization and thermal behavior

Abstract

The metal based phosphate and sulfate mixture, Cu₃(PO₄)₂⋅ 1.65 NaH₂PO₄ ⋅ 1.35 NaHSO₄ has been synthesized and characterized with different measurement techniques. Six different composites such as A1, A2, A3, A4, A5 and A6 have been synthesized by charging different proportions of a mixture with a fixed quantity of wall care putty (Birla make). Similarly, four different composites such as B1, B2, B3 and B4 have been synthesized by charging different proportion of a mixture with a fixed quantity of CaCO₃ and polyvinyl acetate (PVAc) glue. The C1 mixture has also been synthesized using CaCO₃ and polyvinyl acetate (PVAc) glue without the addition of the mixture. The thermal behavior was evaluated in the temperature range 303 K to 573 K and vice versa in two thermal cycles as well as from 173 K from 298 K for one thermal cycle. The thermal behavior of the mixture was studied at a rate of 10 K min⁻¹ while composites were studied at 5 K min⁻¹. The net specific heat capacities (Cp) of composites are found to be, A2 (-0.11 Jg⁻¹K⁻¹), A3 (-0.13 Jg⁻¹K⁻¹), A6 (-0.12 Jg⁻¹K⁻¹), B1 (-0.13 Jg⁻¹K⁻¹), B2 (-0.10 Jg⁻¹K⁻¹), B3 (-0.11 Jg⁻¹K⁻¹) and B4 (-0.17 Jg⁻¹K⁻¹). These composites can be utilized as heat retardant materials.

Graphical Abstract

Keywords:

• Coating
• DSC
• heat retardant
• wall care putty
• CaCO₃ with PVAc

Acknowledgement

RAD, Research scholar in Dept. of Chemistry, IcfaiTech, IFHE is thankful to the University for necessary financial support. GSB is thankful to the Director, FST, IFHE for granting permission to get associated with this work. The author thanks P.G. Department of Chemistry, Fakir Mohan University for providing necessary laboratory facility for the synthesis of this compound. The author also thanks ST&IC, Cochin University of Science and Technology, Cochin for the sophisticated instrument measurements.

Disclosure statement

This manuscript does not have any conflict of interest that the authors reported.

Funding

No funds, grants, or other support were received.

Authors’ contribution

The corresponding author Trilochan Swain designed the experiment and wrote the initial draft of the manuscript. The author Rudrarapu Aravind performed the experiments while the author G.S. Brahma made the final draft of the manuscript.

Data availability statement

All the data reported in the manuscript, including Figures and Tables are included in the supplementary material file.