Partially aromatic polyamides based on tetraphenylthiophene diamine: Synthesis and characterization

Tetraphenylthiophene diamine (TPTDA), was prepared through a modified three -step route to achieve an improved overall yield. TPTDA reacted with succin ic, adipic, suberic, sebasic, and fumaric acids via the Yamazaki phosphoryl ation method to yield novel partially aromatic polyamides (TPT series). A c ounterpart polyamide series based on p-phenylene diamine (Ph series) was al so synthesized under the same conditions. All of the polymers were characte rized by means of spectrochemical (Fourier transform infrared spectroscopy, H-1-nuclear magnetic resonance (NMR), and C-13-NMR) and thermal (different ial scanning calorimetry and thermogravimetric) methods of analysis. Solubi lity of TPT polyamides was clearly improved due to the presence of the bulk y aromatic diamine as well as flexible CH2-CH2 segments. The highly phenyla ted thiophene diamine moiety was recognized to improve thermal stability of the TPT polyamides in comparison with Ph polyamides (integral procedural d ecomposition temperature (IPDT) 480-517 degrees C against 454-485 degrees C ). A favorable balance was recognized in regard to solubility, thermostabil ity, and melting temperature in the TPT polyamides, especially TPT4 and TPT 6. Therefore, they may be considered good candidates for processable polyme rs. (C) 2000 John Wiley & Sons, Inc.