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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 1 H NMR, 13 C 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 dUg and (7.4-15.2) x 10 4 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.

A study for the development of a new, economical manufacturing process for high-molecular-weight poly(amide-imide) (PAI) was performed via direct polycondensation of trimellitic acid anhydride (TMA) or diimide diacids (DIDAs) with aromatic diamines using an equimolar amount of thionyl chloride in NMP at relatively low temperatures. The polyamidation of DIDAs and diamines for head-to-head polymers (H-PAIs) was sensitive to the reaction temperature and proceeded very quickly, 1 h was sufficient to complete the reaction. The highest value of inherent viscosity, ηinh, of 72 mL g−1 was obtained by polymerization at room temperature. Also several randomly sequenced polymers (R-PAIs) were prepared by polycondensation from TMA and diamines, followed by imidization with various methods, such as using TPP as a co-condensing agent, azeotropic dehydration of polyamic acid (PAA) and solid-state imidization from PAA. Solid state imidization from polyamic acids at 235°C gave satisfactory results with an inherent viscosity 58–85 mL g−1. Solvent content, imidization temperature and time were major controlling factors for the degree of imidization as well as for the molecular weight. Both H-PAI and R-PAI showed good mechanical properties with tensile strength of 118–131 MPa and Tg ranged between 263–299°C depending on the nature of monomers. The melt viscosity of the PAIs ranged between 7.4 · 103 and 4.5 · 103 Pa s for H-PAI and R-PAI respectively. These values are comparable to that of conventional PAI, Torlon® 4000T of 5.6 · 103 Pa s. Ein neues, wirtschftliches Verfahren zur Herstellung hochmolekularer Poly(amidimid)e (PAIs) basiert auf der direkten Polykondensation von Trimellitsaureanhydrid(TMA) oder Diimid-Disauren (DIDAs) mit aromatischen Diaminen in Gegenwart von aquimolaren Mengen an Thionylchlorid in N-Methylpyrrolidon bei relativ niedrigen Temperaturen. Die Polyamidierung von Diimid-Disauren und Diaminen zu Kopf-Kopf-Polymeren (H-PAIs) ist temperaturempfindlich und verlauft rasch; die Reaktionsdauer von 1 h war fur die vollstandige Umsetzung ausreichend. Der hochste Wert fur die inharente Viskositat ηinh wurde mit 72 mL g−1 bei Polymerisation bei Raumtemperatur erzielt. Durch die Polykondensation von TMA mit Diaminen und anschliesende Imidisierung nach verschiedenen Methoden, wie die azeotrope Dehydrierung bzw. die Festphasenimidisierung von Polyamsauren oder der Einsatz von Triphenylphosphit als Cokondensationsagens, wurden ebenfalls einige statistisch aufgebaute Polymere (R-PAJs) hergestellt. Von den Imidisierungsmethoden ergab die Festphasenimidisierung von Polyamsauren mit inharenten Viskositaten ηinh von 58–85 mL g−1 zufriedenstellende Ergebnisse. Imidisierungsgrade und Molekulargewichte wurden im wesentlichen von der Losungsmittelmenge sowie der Imidisierungstemperatur und -zeit bestimmt. Sowohl H-PAI als auch R-PAI zeigten gute mechanische Eigenschaften, je nach Ausgangsmonomeren lagen die Zugfestigkeiten im Bereich 118–131 MPa und die Glasubergangstemperaturen im Bereich von 263–299°C. Die Schmelzviskositaten der PAIs bewegten sich zwischen 7,4·103 und 4,5·103 Pa s fur H-PAI bzw. R-PAI und sind mit dem Wert fur konventionelles PAI, Torlon® 4000T, von 5,6·103 Pa s vergleichbar.

A series of novel polyamides carrying NLO chromophores were synthesized and their general properties were characterized. The electrooptic properties of a couple of selected compositions were studied. These polyamides were synthesized by direct polycondensation at 100°C of 4,4′-methylenedianiline or 4,4′-oxydianiline with 4-nitro-[ N,N -bis(2-carboxyethyl)]aniline or 4-[ N,N -bis(2-carboxyethyl)amino]-4′-nitrostilbene in the presence of a condensing agent composed of lithium chloride and triphenyl phosphite. All of the polymers were found to be amorphous and their glass transition temperatures were about 160°C. In contrast, the polymer that does not carry the nitro group in the phenyl ring of the side group revealed a T g value of only 78°C. This difference strongly indicates that the nitro group is involved in the formation of hydrogen bonds and, thus, hinders the chain mobility resulting in the enhanced T g values. This could be confirmed by the i.r.-spectroscopic analysis of the polymers. The u.v.-vis. absorption characteristics of the polyamides also were studied. The second-order nonlinear optical properties of the thin films of two selected polymers of better solubility were studied by measuring their electrooptic coefficients after being poled at the temperatures near their T g s. When the polymer films were poled at the field strength of 0.4–0.6 MV cm −1 , their electrooptic coefficients obtained for the incident beam of 1.3 μm were about 3 pm V −1 and they showed an excellent temporal stability even at 80°C.

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 mbisaminophenoxydiphenylsulfone1 (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 Tg'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 · 103 ∼ 2.1 · 103 Pa · s, thus, the reported PAIs may be considered to be new candidates for melt processable high-performance polymer materials. 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 liesen Isophorondiamin (IPDA) als geeigneteres Comonomeres fur Poly(amidimid)e erscheinen. Die erhaltenen Copoly(amidimid)e zeigten, das 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 ∼ 118 mPa. Die Glastemperaturen liegen je nach Molekulargewicht und dem eingesetzten Comonomeren zwischen 232°C und 301°C. Die Loslichkeit konnte durch den aliphatischen Charakter des IPDA erhoht werden. Auch die rheologischen Eigenschaften verbesserten sich im Vergleich zu konventionellem PAI. Die Schmelzviskositaten der Copolymeren lagen zwischen 1.6 · 103 und 2.1 · 103 Pa · s. Die beschriebenen PAIs konnten sich somit zur Herstellung von aus der Schmelze verarbeitbaren Hochleistungspolymeren eignen.

This work is supported by the Korean Collaborative Project for Excellence in Basic System IC Technology (System IC 2010: 98- B4-C0-00-01-00-02). Financial support from the Ministry of Science and Technology (MOST) and the Korean Ministry of Education through the National Research Laboratory Fund and the Brain Korea 21 Program, respectively, is also greatly acknowledged.