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## Studies on the crystallization of CL-20 with the use of ultrasounds and its effect on the morphology and the sensitivity of the obtained crystals

### Bartosz Zakościelny

#### Abstract

In recent years, numerous studies had been conducted on 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20, HNIW), explosive material of cage construction. CL-20 is a white crystalline body found in a number of polymorphic variants with different properties especially the density. The highest density is obtained for  polymorph which is close to the calculated theoretical maximum density of the organic compound (containing no metal atoms), ongoing works are aimed at getting the purest, in terms of polymorphic variety, of this polymorph. The resulting explosive is characterized by the highest currently achieved parameters of explosives, higher than HMX or RDX. HNIW is a compound sensitive to mechanical stimuli, is necessary to use appropriate safety measures when working with it. These properties can be adjusted by the ways of crystallization, or phlegmatization. A series of crystallization with use of the ultrasonic method and with variable parameters were conducted to investigate their impact on the quality of the crystals. The test system was a mixture of solvent-nonsolvent made from ethyl acetate - chloroform, and the parameters studied were the time of dropwise addition of chloroform to the system, its amount and intensity of mixing. allow running crystallization process without the need of heteronucleation, so the crystallizations were carried out without this step. A Sonocrystallization with heteronucleation was conducted, in order to compare the sensitivity parameters. Crystallizations were studied to determine their physicochemical properties and resistance to mechanical stimuli. A study of performance, chemical purity, crystallographic purity and density obtained and tests performed on the Peters apparatus and Kasts hammer. Use of sonocrystallization produced less sensitive products then derived through classical crystallization. Of the studied parameters time of dropwise addition of chloroform proved to, the least significant mixing speed. Crystallization performed using ultrasound and heteronucleation has led to a product characterized by the highest resistances to both friction and impact.
Record ID
WUT9fa9dd0dd9ec4585b588e9f1b1a375ec
Diploma type
Master of Science
Author
Bartosz Zakościelny Bartosz Zakościelny,, Undefined Affiliation
Title in Polish
Supervisor
Paweł Maksimowski (FC/DH-EM) Paweł Maksimowski,, Department Of High-Energetic Materials (FC/DH-EM)Faculty of Chemistry (FC)
Certifying unit
Faculty of Chemistry (FC)
Affiliation unit
Department Of High-Energetic Materials (FC/DH-EM)
Study subject / specialization
, Technologia Chemiczna
Language
(pl) Polish
Status
Finished
Defense Date
29-06-2012
Issue date (year)
2012
Keywords in Polish
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Keywords in English
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Abstract in Polish
urn:pw-repo:WUT9fa9dd0dd9ec4585b588e9f1b1a375ec