Preparation and properties of new aromatic polyamides from 4,4′‐diaminotriphenylamine and aromatic dicarboxylic acids

Hsiao

1999

ABSTRACT:An ether diamine monomer containing the cyclohexane structure, l,l-bis[4-(4-aminophenoxy)phenyl]cyclohexane (BAPC), was prepared through nucleophilic substitution reaction of l,l-bis(4-hydroxyphenyl)cyclohexane and p-chloronitrobenzene in the presence of K 2C03 , followed by catalytic hydrazine reduction. Using triphenyl phosphite and pyridine as condensing agent, novel polyamides were directly polycondensated from BAPC with various aromatic dicarboxylic acids in the N-methyl-2-pyrrolidone (NMP) solution containing dissolved calcium chloride. The resulting polyamides had inherent viscosities from 0.97 to 1.6ldLg-1 . Most had good solubility in polar organic solvents such as NMP and N,N-dimethylacetamide, and afforded transparent, flexible, and tough films by solution casting. The glass transition temperatures (T.) of the polymers were 188-240oC and 10% mass loss temperatures were recorded at 473-499°C in air. A comparative study on the properties with corresponding polyamides derived from 1, I-bis[ 4-( 4-carboxyphenoxy)phenyl]cyclohexane (BCPC) was made.

Section: Measurementsmentioning

confidence: 99%

Synthesis and Properties of Polyamides Based on 1,1-Bis[4-(4-aminophenoxy)phenyl] cyclohexane

Hsiao

1999

“…Carbon by elemental analysis was found lower than the calculated value and a trace amount of residue was observed after elemental analysis, probably due to the formation of char characteristic of heat resistant polymers. 36 Out of 18 combinations studied, 9 soluble polyimides were obtained. In these cases, clear polyimide solutions in NMP were eventually obtained.…”

Section: Polymer Synthesis and Characterizationmentioning

confidence: 99%

Soluble Polyimides Based on Alkyldiaminobenzophenone

Tsuda

Kawauchi

Hiyoshi

et al. 2000

ABSTRACT:The synthesis and characterization of a novel series of soluble polyimides based on alkyldiaminobenzophenone (ADBP) having long chain linear alkyl groups with 9-14 carbon atoms are described. Polyimides containing tetracarboxylic dianhydrides such as 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA) and ADBP with even number carbon atoms were soluble in polar solvents such as N-methyl-2-pyrrolidone (NMP), while polyimides containing BTDA and ADBP with odd number carbon atoms (ADBP-9, 11, 13) were insoluble in NMP. These unique odd-even effects of solubility were assumed due to the conformational effects of long chain linear alkyl groups. Soluble copolyimides based on ADBP with conventional aromatic diamine, diaminodiphenylether (DOE) can be obtained. The incorporation ofDDE resulted in increment of molecular weight and improve the thermal stability. Soluble polyimides and copolyimides based on ADBP were soluble in various polar solvents and exhibited high thermal stability in air and nitrogen.KEY WORDS Polyimide / Soluble Polyimide / Alkyldiaminobenzophenone / Odd-Even Effect/ Copolymerization / Thermal Stability/ Solubility/ Polyimides exhibit excellent thermal and mechanical properties and have extensive engineering and microelectronics applications.

“…All polymers were entirely insoluble in methanol, acetone, chloroform and tetrahydrofuran. The solubility of the tetraphenylnaphthalene-based polyamides was lower than that of aromatic polyamides having similar phenyl-pendant structures such as tetraphenylthiophene, 2 -5 tetraphenylfuran, 6 tetraphenylpyrrole, 7 tetraphenylethylene, 8 triphenylamine, 9 and triphenylphosphine, 10 previously reported soluble in NMP at room temperature. The rigid terphenyl structure without hetero-atom in the tetraphenylnaphthalene may cause the low solubility.…”

Section: Polymer Synthesismentioning

confidence: 86%

“…Several attempts have been made to improve the solubility by modifying the structure without losing their good thermal stability. Aromatic polyamides having phenyl-pendant structures such as tetraphenylthiophene, 2 -5 tetraphenylfuran, 6 tetraphenylpyrrole, 7 tetraphenylethylene, 8 triphenylamine, 9 triphenylphosphine, 10 triphenylbenzene, 11 hexaphenylbenzene, 12 and tetraphenylquinquephenyl, 13 have high thermal stability and high solubility. We conducted the synthesis of a new diamine monomer, 1 ,4-bis( 4-aminophenyl)-2,3-diphenylnaphtalene and aromatic polyamides derived from it.…”

mentioning

confidence: 99%

Synthesis and Characterization of Novel Aromatic Polyamides from 1,4-Bis(4-aminophenyl)-2,3-diphenylnaphthalene and Aromatic Dicarboxylic Acids

Morikawa

Hatakeyama

1999

ABSTRACT:A new highly phenylated diamine, 1,4-bis(4-aminophenyl)-2,3-diphenylnaphthalene, was synthesized in two steps starting from 2,5-bis(4-nitrophenyl)-3,4-diphenylcyclopentadienone. New aromatic polyamides containing tetraphenylnaphthalene unit were prepared by low temperature solution polycondensation of this diamine with various aromatic dicarboxylic acid chlorides. These polyamides had inherent viscosities of0.45---0.82 dlg-1 . Polyamides with m-phenylene moiety and flexible connecting group were soluble in various organic solvents such as N,N-dimethylacetamide and N-methyl-2-pyrrolidone, but those with rigid symmetric structures were soluble in only hot N,N-dimethylacetamide and N-methyl-2-pyrrolidone. The glass transition temperature of the polyamides ranged from 268 to 366°C, and the 10% weight loss temperatures were above soooc in air. KEY WORDSHigh Temperature Polymers I Soluble Aromatic Polyamides I 1,4-Bis(4-aminophenyl)-2,3-diphenylnaphthalene I Thermal Behavior I Aromatic polyamides are high thermal stability coupled with high crystallinity and hence high temperature application especially as fibers. 1 However, most wholly aromatic polyamides are difficult to fabricate because of low solubility and high melting temperature. Several attempts have been made to improve the solubility by modifying the structure without losing their good thermal stability. Aromatic polyamides having phenyl-pendant structures such as tetraphenylthiophene, 2 -5 tetraphenylfuran, 6 tetraphenylpyrrole, 7 tetraphenylethylene, 8 triphenylamine, 9 triphenylphosphine, 10 triphenylbenzene, 11 hexaphenylbenzene, 12 and tetraphenylquinquephenyl, 13 have high thermal stability and high solubility. We conducted the synthesis of a new diamine monomer, 1 ,4-bis( 4-aminophenyl)-2,3-diphenylnaphtalene and aromatic polyamides derived from it. This article deals with the synthesis and characterization of novel aromatic polyamides from this diamine and aromatic dicarboxylic acid chlorides. The properties of polyamides such as solubility and thermal behavior are also discussed.