Fiber-forming organoyttroxanealumoxanes

Synthesis of Preceramic Organomagnesium Oxanealumoxane Siloxanes

“…It was previously found that the interaction of ethyl acetoacetate alkoxyhydroxyalumoxanes [12] with magnesium acetylacetonate proceeds primarily along hydroxyl groups with the formation of Mg−О−Al bonds and the release of acetylacetone. The resulting acetylacetone reacts with ethoxy groups of ethyl acetoacetate ethoxyhydroxyalumoxanes, C2H5O-are partially replaced by -OC (CH3) = CHC (O) CH3 to produce alcohol, which is confirmed by the absence of the distillate obtained after the synthesis of organomagnesiumoxane alumoxane in toluene in 13 C NMR spectra, 13 C signals typical for acetylacetone functional groups. We found that organomagnesiumoxane alumoxanes are alumoxanes with organomagnesiumoxane groupings in the side chain at aluminum.…”

“…In all spectra, three groups of signals at (−)82-(−)89, (−)90-(-)94, (−)96-(−)100 ppm, corresponding to (EtO)3SiO, (EtO)2SiO2 и SiO4 groups can be identified ( Figure 5). It should be emphasized that organomagnesiumoxane alumoxane siloxanes may have fiber-forming properties (characteristic temperatures [13] are presented in Table 4. Figure 8 presents photos of manually produced fibers.…”

“…IR spectra were recorded on «Nicolet» iS50R in the range of 400-4000 cm −1 by a Smart iTR single attenuated total reflection (ATR) multipurpose accessory (diamond crystal). 1 Н, 13 С, 17 О, 27 Al, 29 Si NMR spectra of organomagnesiumoxane alumoxane siloxanes were determined for solutions in deuterochloroform-CDCl3 by AVANCE-600 (BRUKER).…”

“…29 Si NMR spectra of organomagnesiumoxane alumoxane siloxanes. In 1 Н,13 С NMR spectra of organomagnesiumoxane alumoxane siloxanes the following signals are recorded: 1 H-NMR (600.13 MHz, CDCl3) broad 0.7-1.5 ppm CH3 (С2H5O−); broad 1.5-2.4 ppm CH3 of acetoxy group; broad 3.5-4.5 ppm CH2 (С2H5O−); broad 4.5-5.6 ppm CH (CH=);13 С-NMR (600.13 MHz, CDCl3) broad 13-20 ppm CH3 (С2H5O−); broad 24-27 ppm CH3 of acetoxy group; broad 57-61 ppm CH2 (С2H5O−); broad 99-103 ppm CH (СH=); broad 170-175 ppm CO(O); broad 184-195 ppm C=O. The interpretation of the absorption bands of organomagnesiumoxane alumoxane siloxanes observed in the IR spectrum (Figure 6) is as follows: IR (cm −1 ), 595 ν(Mg−О−Al), 659, 688 ν(Mg−О; Al−О; Si−О), 863 ν(Al−О−Al), 940 ν(Mg−О), 967 ν(Al−О4; Si−О), 1030, 1071, 1101, 1176 ν(Mg−О−С; Al−О−С; Si−О−С), 787, 1268, 1291, 1303, 1398 δ{СН, C(CH3)} and ν(С-О), 1533 ν(С=С), 1602 ν(С=О from [CH3(O)CCH=C(CH3)О]), 1635 ν(С=О, bonded by coordination bond with Al atom), 2899, 2927, 2977 ν(СН), 3415 ν(ОH); it somewhat difficult due to the similarity of the spectra of the starting organoalumoxanes, (acac)2Mg and ethylsilicate-40.…”