2917-61-5Relevant academic research and scientific papers
Synthesis and characterization of polyurethanes bearing carbosilane segments
Karimata, Ayumu,Matsumoto, Kozo,Endo, Takeshi
, p. 94803 - 94808 (2016)
Novel polyurethanes bearing carbosilane segments (1a-c) were synthesized. Their thermal and mechanical properties were compared with corresponding reference polyurethanes bearing carbon-based backbone (2a-c). The thermal properties of these polyurethanes were investigated by DSC and TGA. Glass transition temperature was significantly reduced by substituting carbon atom with silicon (1a-c). Moreover, the thermal decomposition temperature of 1a-c was found to be comparable to 2a-c. Furthermore, Young's moduli of 1a-c were lower than those of 2a-c. A large potential of carbosilane unit as a soft segment for building new polyurethanes have been demonstrated in this paper.
Energetic Sila-Nitrocarbamates: Silicon Analogues of Neo-Pentane Derivatives
Axthammer, Quirin J.,Klap?tke, Thomas M.,Krumm, Burkhard,Reith, Thomas
, p. 4683 - 4692 (2016/05/24)
Four silanes based on the neo-pentane skeleton Me4-xSi(CH2R)x containing carbamate groups (x = 1-4, R = OC(O)NH2) have been prepared via the corresponding alcohols Me4-xSi(CH2OH)x, starting from the chlorosilanes Me4-xSiClx. Subsequent nitration leads to the corresponding primary nitrocarbamates (R = OC(O)NHNO2), examined for the purpose as potential energetic materials, including the silicon analogue of pentaerythritol tetranitrocarbamate (sila-PETNC) and a siloxane based nitrocarbamate side-product. All compounds were thoroughly characterized by spectroscopic methods including X-ray diffraction. Thermal stabilities and sensitivities toward impact and friction were examined, as well as detonation values by calculating energies of formation using the EXPLO5 V6.02 software.
Sila-Substitution of Alkyl Nitrates: Synthesis, Structural Characterization, and Sensitivity Studies of Highly Explosive (Nitratomethyl)-, Bis(nitratomethyl)-, and Tris(nitratomethyl)silanes and Their Corresponding Carbon Analogues
Evangelisti, Camilla,Klapoetke, Thomas M.,Krumm, Burkhard,Nieder, Anian,Berger, Raphael J.F.,Hayes, Stuart A.,Mitzel, Norbert W.,Troegel, Dennis,Tacke, Reinhold
experimental part, p. 4865 - 4880 (2010/08/06)
A series of analogous nitratomethyl compounds of carbon and silicon of the formula types Me3ElCH2ONO2 (1a/1b), Me 2El(CH2ONO2)2 (2a/2b), MeEl(CH 2ONO2)3 (3a/3b), (CH2) 4El(CH2ONO2)2 (4a/4b), and (CH 2)5El(CH2ONO2)2 (5a/5b) were synthesized [El = C (a), Si (b); (CH2)4El = (sila)cyclopentane-1,1-diyl; (CH2)5El = (sila)cyclohexane-1,1-diyl]. All compounds were characterized by using NMR, IR, and Raman spectroscopy and mass spectrometry. In addition, the crystal structures of Me2C(CH2ONO2)2 (2a), (CH2)4C(CH2ONO2)2 (4a), Me2Si(CH2ONO2)2 (2b), and (CH 2)5Si(CH2ONO2)2 (5b) were determined by single-crystal X-ray diffraction. The gas-phase structures of the C/Si analogues 1a and 1b were determined by electron diffraction and compared with the results of quantum chemical calculations at different levels of theory. The thermal stabilities of the C/Si pairs 1a/1b-5a/5b were investigated by using DSC. In addition, their friction and impact sensitivities were measured with standard BAM methods. The extreme sensitivities of the silicon compounds 1b-5b compared to those of the corresponding carbon analogues 1a-5a were discussed in terms of the structures of the C/Si analogues and possible geminal Si???O interactions.
