Indian Journal of Engineering & Materials Sciences Vol. 5, June 1998, pp. 140-144 Studies on energetic compounds Part 9: Preparation and thermal decomposition of 1- and 2-naphthylammonium nitrates and perchlorates Gurdip Singh", Inder Pal Singh Kapoor & Smiju Jacob Department of Chemistry, DDU Gorakhpur University, Gorakhpur 273009, India Received 17 December 1997; accepted 27 April 1998. 1- and 2-naphthylammonium nitrates and perchlorates have been prepared and characterised. Thermal and explosive characteristics of these salts are studied by TG, DSC and ignition delay measurements. Suitable decomposition pathways have also been proposed. The preparation, characterisation and thermal decomposition of alkyll.2 and aryl 3-8 ammonium nitrates and perchlorates have been extensively studied because of the technological use of these compounds, especially in pyrotechnics, explosives and solid propellants. As a part of the ongoing research programmes on thermolysis of energetic materials, studies on the nitrates and perchlorates of l+and 2-naphthylamines have been carried out and results are reported in the present com- munication. Experimental Procedure Preparation and characterisation of naphthyl- ammonium nitrates and perchlorates-l- and 2- naphthylammonium nitrates (NAN) were prepared by the reaction of 20% HN0 3 with 1- and 2- naphthylamines (I: I) respectively at 0 - 5 °C (Scheme 1). 1- and 2- naphthylammonium perchlo- rates (NAP) were prepared by reacting 20% HCI0 4 with 1- and 2- naphthylamines (1: 1) respectively at room temperature (Scheme I). The mixture was concentrated at 60°C under rotary vacuum evaporator and cooled to obtain crystalline solid. All the four salts were recrystallised from absolute alcohol, crystals were vacuum dried and purity was checked by TLC. Moreover these are characterised by gravimetric (using nitron reagent)", IR and UV spectra'?' II (Table 1). Thermal decomposition studies on NAN and NAP-Thennal decomposition of NAN and NAP was carried out using following techniques: ·For correspondence Non-isothermal TG-TG studies on nitrates and perchlorates (wt. 10 mg, 100-200 mesh) were undertaken in static air at a heating rate of 5°C/min using indigenously fabricated TG apparatus'< fitted with temperature indicator cum controller (Model CT 808T Century) and bucket type gold crucible 20% HNO, + - C,oH,NH,NO, I· & 2· naphathylanunonium nitrates 0-5°C CIOH,NH, I· & 2· naphalhylamine ,--2_00/._0.".HC"::-IO-,-,,,--. RT + - C,oH7NH,ClO. I· & 2· naphalhylammonium pcrchlorates Scheme 1 (height = 8 mm, diameter = 8 mm). Fraction decomposed (a) versus temperature (OC) plot is given in Fig. 1. DSC-DSC thermograms on NAN and NAP were obtained on a Mettler TA 4000 in nitrogen atmosphere (flow rate 40 em' Imm.). Weighed samples (Sartorius-Werke Type 2405 electro balance, Germany) were sealed with sample sealer. A pin hole was made at the top of the lid so that the product gases could escape during decomposition. The sample and the reference pans were positioned at the centre of the holder cells and were covered with aluminium domes. The thennograms (Fig. 2) were recorded at a heating rate of 10°C/min using Hewlett Packard 7475A plotter. Ignition delay and ignition temperature measurements-30 mg of the sample was taken in an ignition tube (height = 5 em and diameter = 0.4 ern) and the time between the insertion of the