Facile synthesis of a melt-spinnable polyborazine from asymmetric alkylaminoborazine

A simply prepared flexible SiBOC ultrafine fiber mat with enhanced high-temperature stability and chemical resistance

A simply prepared flexible SiBOC ultrafine fiber mat with high-temperature stability and chemical resistance. I: A typical SiBOC material composed of Si, B, O and C. II: A comparison of SiBOC fibers and SiOC fibers treated under different conditions.

Polymerization of N-methyl B-methyl amino borazine

A large quantity of high-quality poly[N-methyl B-methyl amino borazine] was synthesized via a solventless method from the monomer 1,3,5-trimethyl-2,4,6-tri(methyl amino)borazine. The thermal polymerization profile was investigated with differential scanning calorimetry (DSC), Fourier transform infrared (FTIR), size exclusion chromatography (SEC), gas chromatography, and mass spectrometry. A polymerization mechanism involving the condensation reaction of two –N(H)CH3 groups releasing methylamine was proposed and compared with the literature. As a result of cross-linking via the amino­methyl moiety, the cured polymer exhibited a molecular weight Mn of 790 g mol-1, glass transition temperature of 64°C, high cross-link density, and thermal stability with a decomposition temperature of 165°C. Functionalized poly[N-methyl B-methyl amino borazine] with chemical stability was fully characterized by 1H, 13C, 11B nuclear magnetic resonance, FTIR, DSC, and SEC analyses. Ultraviolet absorption spectra evidenced changes in the structure of the aforementioned oligomers.