Preparation and characteristics of a novel PETN/TKX-50 co-crystal by a solvent/non-solvent method

• Published in: RSC advances 2019-03, Vol.9 (16), p.924-921
• Main Authors: Xiao, Lei, Guo, Shuangfeng, Su, Hongping, Gou, Bingwang, Liu, Qiaoe, Hao, Gazi, Hu, Yubing, Wang, Xiaohong, Jiang, Wei
• Format: Article
• Language: English
• Subjects: Chemistry; Crystal structure; Crystals; Differential scanning calorimetry; Fourier transforms; High performance liquid chromatography; Hydrogen bonds; Infrared spectroscopy; Morphology; PETN; Photoelectrons; Raman spectra; Raman spectroscopy; Raw materials; RDX; Scanning electron microscopy; Sensitivity; Solvents; Thermal decomposition; Thermal stability; Thermogravimetry; Trinitramine; X ray photoelectron spectroscopy; X-ray diffraction
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/c8ra10512j

In order to decrease the sensitivity and broaden the application of pentaerythritol tetranitrate (PETN), a novel energetic co-crystal composed of PETN and dihydroxylammonium 5,5′-bistetrazole-1,1′-diolate (TKX-50) with high energy and low sensitivity was successfully prepared through the solvent/non-solvent method. The morphology and structure of the as-prepared co-crystal were characterized by scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectrometry (XPS), fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy and high performance liquid chromatography (HPLC). The thermal decomposition properties were also analyzed by simultaneous thermogravimetry and differential scanning calorimetry (TG-DSC). The safety performance was judged by mechanical sensitivity tests. The SEM results revealed that the prepared new material was homogeneous with a mean granularity of 1 μm and the morphology was distinct from raw PETN and TKX-50. The XRD analysis indicated that a new crystalline formation appeared in the co-crystal which was quite different from the raw materials and their mixture. The XPS analysis showed peak shifts of C, N, O elements in the co-crystal. The FTIR spectra and Raman spectra suggested that hydrogen bond interactions existed between PETN and TKX-50 molecules. The molar ratio of PETN and TKX-50 was 1 : 1 determined by HPLC. There were two thermal decomposition peaks (194.1 °C and 261.3 °C) for the co-crystal at 20 °C min −1 , while the raw materials and mixture had only one. Besides, the activation energy of the co-crystal increased compared to the raw materials, indicating better thermal stability of the co-crystal. The impact sensitivity and friction sensitivity of the PETN/TKX-50 co-crystal were reduced compared to raw PETN, and were even better than for 1,3,5-trimethylene trinitramine (RDX). The results showed a prospective application of the prepared PETN/TKX-50 co-crystal in the future. In order to decrease the sensitivity and broaden the application of PETN, PETN/TKX-50 co-crystal with high energy and low sensitivity was prepared through the solvent/non-solvent method.