Title: EVALUATING SOLVENT EFFECT IN THE SYNTHESIS OF AROMATIC DIAIMNE-BASED POLYBENZOXAINES
Authors: Benjamin L.G. Morasch, Jeffrey S. Wiggins
Abstract: Polybenzoxazine chemistry is an attractive alternative to more traditional matrices used in the aerospace industry due to the high glass transition temperature, high moduli, and volatile-free cure. Aromatic diamine-based benzoxazine monomers exhibit significant improvements in thermal stability over the traditional bisphenol-based counterparts but are reported infrequently in literature. The one-pot synthetic method that is well documented for bisphenol-based benzoxazines produces an intermediate hexahydrotriazine network leading to gelation when extended to aromatic diamines. In this paper, the challenging synthesis associated with aromatic diamine-based benzoxazine monomers was evaluated by studying the significance of experimental parameters including reaction temperature, time, and solvent type. Attenuated total reflectance Fourier transfer infrared spectroscopy (ATR-FTIR) and nuclear magnetic resonance spectroscopy (NMR) confirmed monomer structures then thermal properties were assessed via dynamic scanning calorimetry (DSC) and thermogravimetric analysis (TGA). This research aims to contribute towards understanding the synthetic conditions that enable high purity aromatic-based diamine benzoxazines to facilitate future research of this promising thermoset.
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Conference: SAMPE 2023
Publication Date: 2023/04/17
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