A series of novel aromatic diamines (1−3) containing kinked cyclohexylidene moieties was synthesized by a reaction of excess aniline and corresponding methyl-substituted cyclohexanone derivatives. The structures of (1−3) were identifield by 1H NMR, 13C NMR, and FT-IR. The polymers were synthesized from the obtained diamines and various aromatic dianhydrides by the conventional polycondensation reaction followed by chemical imidization as well as high-temperature one-step polymerization. The inherent viscosities and weight-average molecular weights of the resulting polyimides were in the ranges of 0.55−1.58 dL/g and (7.4−15.2) × 104 g/mol, respectively. The prepared polyimides showed excellent thermal stabilities and good solubility. All polymers were readily soluble in common organic solvents such as tetrahydrofuran, chloroform, tetrachloroethane, etc., and the glass transition temperatures were observed at 290−372 °C.

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New poly(amideimide)s (PAI) containing aliphatic diamines as comonomers were synthesized by polycondensation of trimellitic anhydride chloride with mixed diamines. Preliminary results of copolymerization with various alicyclic diamines suggested that isophoronediamine (IPDA) is more preferable as a comonomer for PAI. The copolyamide imides with IPDA showed that IPDA is more rigid than mbisaminophenoxydiphenylsulfonea (m-BAPS) and 4,4'-diaminodiphenyl ether (ODA), but less than m-phenylenediamine (m-PDA). And they showed good mechanical properties with 105 -118 MPa of tensile strength and T,'s were ranged 232 -301 "C depending on molecular weight and comonomers. The solubility was improved due to the aliphatic character of IPDA in the copolymers. Rheological properties were also improved compared with conventional PAI. The melt viscosity of the copolymers ranged 1.6. lo3 -2.1 . lo3 Pa s, thus, the reported PAIs may be considered to be new candidates for melt processable high-performance polymer materials. ZUSAMMENFASSUNG:Neuartige Poly (amidimid)e (PAI) mit aliphatischen Diaminen als Comonomersegmente wurden durch Polykondensation von Trimellitsaureanhydridchlorid mit gemischten Aminen hergestellt. Die Ergebnisse von Copolymerisationsversuchen mit verschiedenen alicyclischen Diaminen lieBen Isophorondiamin (IPDA) als geeigneteres Comonomeres fur Poly(amidimid)e erscheinen. Die erhaltenen Copoly(amidimid)e zeigten, daR die IPDA-Segmente im Vergleich zu aromatischen Diaminen, die in einer vorangehenden Arbeit beschrieben wurden, starrer sind als m-BAPS und 4,4'-Diaminodiphenylether, jedoch weniger starr als m-PDA. Die hergestellten PAIs besitzen gute mechanische Eigenschaften mit Zugfestigkeiten von 105 -11 8 mPa. Die Glastemperaturen liegen je nach Molekulargewicht und dem eingesetzten Comonomeren zwischen 232 "C und 301 "C. Die Ltjslichkeit konnte durch den aliphatischen Charakter des IPDA erhoht werden. Auch die rheologischen Eigenschaften verbesserten sich im Vergleich zu konventionellem PAI. Die SchmelzviskositMen der Copolymeren lagen zwischen 1.6. lo3 und 2.1 lo3 Pa. s. Die beschriebenen PAIs konnten sich somit zur Herstellung von aus der Schmelze verarbeitbaren Hochleistungspolymeren eignen.

In order to improve the solubility of aromatic polyamides without significant loss of thermal stability, synthesis of aromatic polyamides containing pendant silyl groups was carried out by direct polycondensation of silylated aromatic diacids such as 2‐trimethylsilylterephthalic acid (TSTA), 2,5‐bis (trimethylsilyl) terephthalic acid (BTSTA), 5‐trimethylsilylisophthalic acid (TSIA), 5‐dimethylphenylsilylisophthalic acid (DMSIA), and 5‐triphenylsilylisophthalic acid (TPSIA) with various aromatic diamines. The resulting polyamides had inherent viscosities in the range of 0.18–1.10 dL/g and showed improved solubilities toward aprotic polar solvents such as NMP, DMF, DMSO, etc. The prepared aromatic polyamides exhibited fairly good thermal stabilities, which were almost comparable to those of corresponding nonsubstituted aromatic polyamides. That is, thermogravimetric analysis (TGA) data revealed 10% weight losses at 358–500°C and residual weights at 700°C were 46–67% under nitrogen atmosphere. © 1992 John Wiley & Sons, Inc.