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SYNOPSISNovel aromatic polyimides containing bis (phenoxy ) naphthalene units were synthesized from 1,5-bis (4-aminophenoxy ) naphthalene ( APN ) and various aromatic tetracarboxylic dianhydrides by the usual two-step procedure that included ring-opening polyaddition in a polar solvent such as N,N-dimethylacetamide ( DMAc) to give poly (amic acid) s, followed by cyclodehydration to polyimides. The poly (amic acid) s had inherent viscosities between 0.72 and 1.94 dL/g, depending on the tetracarboxylic dianhydrides used. Excepting the polyimide IVb obtained from 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA ) , all other polyimides formed brown, flexible, and tough films by casting from the poly (amic acid) solutions. The polyimide synthesized from BPDA was characterized as semicrystalline, whereas the other polyimides showed amorphous patterns as shown by the x-ray diffraction studies. Tensile strength, initial moduli, and elongation at break of the APN-based polyimide films ranged from 105-135 MPa, 1.92-2.50 GPa, and 6-7%, respectively. These polyimides had glass transition temperatures between 228 and 317°C. Thermal analyses indicated that these polymers were fairly stable, and the 10% weight loss temperatures by TGA were recorded in the range of 543-574°C in nitrogen and 540466°C in air atmosphere, respectively. 0 1993 John Wiley & Sons, Inc.

2,7-Bis(4-aminophenoxy)naphthalene, a new polymer-forming diamine, was synthesized in two steps by the preparation of 2,7-bis(4-nitrophenoxy)naphthalene from 2,7-dihydroxynaphthalene and p-chloronitrobenzene and subsequent reduction with a 10% Pd-C catalyst and hydrazine hydrate. Aromatic polyamides and copolyamides having an inherent viscosity in the range of 0,76-1,16 dL/g were prepared by the direct polycondensation of the diamine with various aromatic dicarboxylic acids or with mixed dicarboxylic acids in 1 -methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Most of the polymers were soluble in aprotic solvents such as NMP and N,N-dimethylacetamide (DMAc), and afforded transparent, flexible and tough films upon casting from DMAc solutions. Glass transition temperatures of the polymers were in the range of 246-327 "C, and 10% weight loss temperatures were above 501 "C in nitrogen and 476 "C in air, respectively.

A new bis(phenoxy)naphthalene‐containing diamine, 1,5‐bis(4‐aminophenoxy)naphthalene, was synthesized in two steps from the condensation of 1,5‐dihydroxy‐naphthalene with p‐chloronitrobenzene in the presence of potassium carbonate, giving 1,5‐bis(4‐nitrophenoxy)naphthalene, followed by hydrazine hydrate/PdC reduction. A series of polyamides and copolyamides were synthesized by the direct polycondensation of the diamine with various aromatic dicarboxylic acids or with mixed dicarboxylic acids in N‐methyl‐2‐pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. The polymers having inherent viscosity of 0.81–1.25 dL/g were obtained in quantitative yield. Most of the polymers were generally soluble in aprotic solvent such as N,N‐dimethylacetamide, N‐methyl‐2‐pyrrolidone, etc. The polymers derived from rigid dicarboxylic acids such as terephthalic acid, naphthalene dicarboxylic acid, and 4,4′‐biphenyldicarboxylic acid exhibited crystalline patterns. Glass transition temperatures of polymers were in the range of 230–360°C, and 10% weight loss temperatures in nitrogen and air were above 492 and 470°C, respectively. © 1993 John Wiley & Sons, Inc.

A new polymer-forming diamine, 2,3-bis(4-aminophenoxy)naphthalene, was synthesized in two steps from the condensation of 2,3-naphthalenediol and p-chloronitrobenzene, giving 2,3-bis(4-nitrophenoxy)naphthalene, followed by the reduction with hydrazine/Pd-C system. A series of novel aromatic polyamides (aramids) were synthesized by direct polycondensation of the diamine with various aromatic dicarboxylic acids in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. These aramids have inherent viscosities of 0,70-1,48 dL/g and were obtained in quantitative yield. The polymers are generally soluble in a wide range of solvents, such as N,N-dimethylacetamide, NMP, dimethyl sulfoxide, pyridine, and tetrahydrofuran, and afford transparent, flexible, and tough films upon casting from their solutions. The glass transition temperatures of these aramids are in the range of 242-267 "C, and the 10% weight loss temperatures are above 503 "C in nitrogen and above 496 "C in air. 0 1993, Hiithig & Wepf Verlag, Base1 CCC 0025-1 16)3/93/$05.00