Condensation polymerization of bis-(salicylaldehydo) metal(II) with diamines

Summary Condensation of bis-(salicylaldehydo) metal (II) (metal = Be, Zn and Cd) and diamines (1,4-diaminobenzene or 4,4-diaminodiphenyl) yield polymeric complexes which have been investigated for their characteristics, composition, structure, thermal stability and polymeric nature. The stable, powdery solids obtained by refluxing 11 bis-(salicylaldehydo) metal-chelate (in DMF) and the diamine (ethanolic) have the composition (-ML-)_n and are insoluble in common organic solvents. I.R. study indicates that salicylaldehyde molecule is bonded to the metal ion through the oxygen atoms of phenolic and aldehydic groups in bis-(salicylaldehydo) metal-chelates. On interaction with the diamines, the polymeric complexes are formed, the nitrogen atoms of the amino groups replacing the aldehydic oxygens. The terminal nitrogens of the diamine, bridge two bis-(salicylaldehydo) metal-chelates, and the polymeric chain grows in a similar manner. The complexes obtained from 4, 4-diaminodiphenyl are thermally more stable than those from 1,4-diaminobenzene. The order of thermal stability of the polymers is : Be Zn>Cd.     

Some New Organometallic Polyamides based on Ferrocene

Three new polyamides containing ferrocene units in the main chain were synthesized via low temperature polycondensation route, reacting 1,1′-ferrocenedicarboxylic acid chloride with three different types of aromatic diamines. The products were characterized by their solubilities, elemental analysis, FTIR spectral analysis, differential scanning calorimetry, thermogravimetry and viscosity measurements. The glass transition temperatures of the polymers were found by DSC curves and the activation energies of pyrolysis were estimated from TG curves applying Horowitz and Metzger method. Among these, polyamide P-1 (prepared from 4-(4-aminophenyloxy)phenyl-4-aminobenzamide) was found soluble in some of the organic solvents at room temperature but has poor thermal stability. Polyamide P-2 (prepared from 1,2-di(para-aminophenyloxy)ethylene) was soluble on heating and is thermally stable. However, all of these were also miscible with concentrated H₂SO₄ forming red coloured solutions.

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Graphical Abstract Ferrocenedicarbonyl chloride was reacted with three different types of aromatic diamines via solution polycondensation to get three new polyamides. Two of which were soluble in some organic solvents. The resulting polymers were characterized by their solubilities, viscosity measurements, elemental analysis, FTIR spectroscopy, differential scanning calorimetric and thermogravimetric studies.

     

Synthesis and characterization of new organo-soluble poly(amide-imide)s based on 1,4-bis(trimellitimido)-2,5-dimethylbenzene

Summary A series of new aromatic poly(amide-imide)s were synthesized by the triphenyl phosphite activated polycondensation of the diimide-diacid, 1,4-bis(trimellitimido)-2,5-dimethylbenzene (I), with various aromatic diamines. The poly(amide-imide)s had inherent viscosities of 1.13–2.22 dL/g. Most of the resulting polymers showed an amorphous nature and were readily soluble in a variety of organic solvents. Transparent, flexible, and tough films of these polymers could be cast from DMAc or NMP solutions. Their cast films had tensile strengths ranging from 64 to 116 MPa, elongations at break from 6 to 20%, and initial moduli from 2.18 to 3.90 GPa. The glass transition temperatures of these polymers were in the range of 247–324°C. Received: 13 April 1999/Revised version: 28 May 1999/Accepted: 26 June 1999     

Synthesis and properties of new poly(amide-imide)s based on 2,5-bis(trimellitimido)toluene

Summary A series of new aromatic poly(amide-imide)s were synthesized by the triphenyl phosphite activated polycondensation of the diimide-diacid, 2,5-bis(trimellitimido)toluene (I) with various aromatic diamines. The poly(amide-imide)s had inherent viscosities of 0.69–1.89 dL/g. Most of the resulting polymers showed an amorphous nature and were readily soluble in a variety of organic solvents. Transparent, flexible, and tough films of these polymers could be cast from DMAc or NMP solutions. Their cast films had tensile strengths ranging from 76 to 112 MPa, elongations at break from 8 to 31%, and initial moduli from 2.20 to 2.99 GPa. The glass transition temperatures of these polymers were in the range of 253–328°C. Received: 25 September 1998/Revised version: 2 December 1998/Accepted: 8 December 1998     

Syntheses and properties of aromatic polyamides derived from 4,4′-oxydibenzoic acid and aromatic diamines

A series of aromatic polyamides were synthesized by direct polycondensation of 4,4-oxydibenzoic acid with various aromatic diamines inN-methyl-2-pyrrolidone (NMP) solution containing dissolved calcium chloride, using triphenyl phosphite and pyridine as condensing agents. The resultant polyamides had inherent viscosities of 0.21-1.48 dL/g. Most of the polymers were organo-soluble and could be solution-cast into flexible and strong films. The glass transition temperatures (T_gs) of most polyamides could be determined with the help of differential scanning calorimetry (DSC) traces, which were recorded in the range of 170–275 °C. Thermogravi metric data of these polymers indicated that most of the polyamides showed no significant weight loss before 450 °C in either air or nitrogen atmospheres.     

Synthesis and properties of polyamideimides containing a bicycloöctene ring

A series of aliphatic and aromatic polyamideimides containing a bicycloöctene ring were synthesized. Low-temperature solution condensation polymerization involving various diamines and N,N′-dichloroformylmethyl-[bicyclo-(2.2.2)-oct-7-ene-2,3,5,6-tetracarb-oxylic acid 2,3,5,6-diimide] (2) were employed. Most of these polymers thus obtained were soluble in m-cresol, DMF, DMAc and DMSO etc. The inherent viscosities of the polymers ranged from 0.07 to 0.40 dl/g (in DMF at 25°C). The polymers obtained from 2 and aromatic diamines showed thermal stabilities above 380°C. The aliphatic polymers were more unstable than the aromatic polymers.     

Preparation and properties of poly(amideether-imide)s derived from 1,4-bis(4-aminophenoxy)benzene,trimellitic anhydride,and various aromatic diamines

An imide ring containing dicarboxylic acid, 1,4-bis(4-trimellitimidophenoxy)benzene (III), was prepared by the condensation of 1,4-bis(4-aminophenoxy)benzene and trimellitic anhydride. A series of new poly(amide-ether-imide)s were prepared by the direct polycondensation of diimide-diacid III with various aromatic diamines using triphenyl phosphite and pyridine as condensing agents inN-methyl-2-pyrrolidone (NMP) in the presence of calcium chloride. The highest inherent viscosity value of a poly(amide-ether-imide) obtained was 1.78 dL/g (inN,N-dimethylacetamide, DMAc, at 30 °C). Flexible films with excellent tensile properties were cast from DMAc solutions. Glass transition temperatures of these poly(amide-ether-imide)s were recorded in the range of 248–297 C. These polymers do not show obvious weight loss before 400°C; the decomposition temperatures at which 10% weight loss in nitrogen and in air were observed for these poly(amide-ether-imide)s in the range of 521–564°C and 501–539°C, respectively. The polymers derived fromp-phenylenediamine or the diamines containing 1,4-bisphenoxy units exhibited a higher degree of crystallinity and higher initial decomposition temperatures but poor solubility in organic solvents.     

Synthesis and characterization of polyamides and poly(amide‐imide)s derived from 2,6‐bis(3‐aminophenoxy)benzonitrile or 2,6‐bis(4‐aminophenoxy)benzonitrile

A series of polyamides and poly(amide‐imide)s was prepared by direct polycondensation of ether and nitrile group containing aromatic diamines with aromatic dicarboxylic acids and bis(carboxyphthalimide)s respectively in N‐methyl 2‐pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. New diamines, such as 2,6‐bis(4‐aminophenoxy)benzonitrile and 2,6‐bis(3‐aminophenoxy)benzonitrile, were prepared from 2,6‐dichlorobenzonitrile with 4‐aminophenol and 3‐aminophenol, respectively, in NMP using potassium carbonate. Bis(carboxyphthalimide)s were prepared from the reaction of trimellitic anhydride with various aromatic diamines in N,N′‐dimethyl formamide. The inherent viscosities of the resulting polymers were in the range of 0.27 to 0.93 dl g^?1 in NMP and the glass transition temperatures were between 175 and 298 °C. All polymers were soluble in dipolar aprotic solvents such as dimethylsulfoxide, dimethylacetamide and NMP. All polymers were stable up to 350 °C with a char yield of above 40 % at 900 °C in nitrogen atmosphere. All polymers were found to be amorphous except the polyamide derived from isophthalic acid and the poly(amide‐imide)s derived from diaminodiphenylether and diaminobenzophenone based bis(carboxyphthalimide)s. Copyright © 2004 Society of Chemical Industry     

Synthesis of New Polyimides from Ru (II) Complex of 2,6-bis [1-(p-dimethylaminophenylimino) Ethyl] Pyridine

Pyridine-based tridentate ligand containing pendant NMe₂ unit was used to prepare novel polyimides via one-stage solution polycondensation due to their stability under a variety of oxidative and reductive conditions. Ru (II) complex of the pydim ligand was synthesized starting from [RuCl₂ (p-cymene)]₂ and 2,6-bis [1-(p-dimethylaminophenylimino) ethyl] pyridine. A series of stable polyimides were synthesized from Ru (II) complex of 2,6-bis [1-(p-dimethylaminophenylimino) ethyl] pyridine (2) and various aromatic dianhyrides had inherent viscosities ranging from 1.31 to 1.55 dL/g and were soluble in polar solvents. The glass transition temperatures were 245–308°C, and the 10% weight loss temperatures were above 482–548°C.     

Synthesis and characterization of thermostable polyamides from unsymmetrical diamines containing flexible ether linkage and different diarylimidazole pendants in ionic liquids

A series of aromatic poly(amide-ether) (PAE)s containing derivatives of imidazole heterocyclic ring and flexible ether linkages was synthesized from polymerization reaction of three new diamines with commercially available aromatic diacids by using two different methods of direct polycondensation: (1) By using triphenyl phosphite (TPP) as activating agent, NMP, pyridine (Py) and LiCl, and (2) by using combination of an ionic liquid (IL) and TPP which allowed to carry out PAEs synthesis without using Py, LiCl and NMP. Room temperature ILs bearing anions such as BF ₄ ^- , Br^-, Cl^-, and PF ₆ ^- with symmetrical 1,3-dialkylimidazolium cations have been prepared and used as polycondensation media. The polymers were obtained in good yields with moderate viscosity (0.47?C0.68 dL/g) in a shorter time of reaction (2.5?h) in comparison with the PAEs obtained in NMP (12?h). All of these polymers were amorphous in nature, showed excellent solubility in amide-type polar aprotic solvents. These polymers showed good thermal stability with glass transition temperatures (T_g) between 212?C355?°C and 10?% weight loss temperatures were recorded around 421?°C and 460?°C in air and N₂, respectively. These polymers showed blue flourescence emission in the range of 460?C505?nm and can be candidate for applications in photoluminescent devices.     

Phase-transfer catalyzed synthesis of poly(etherketone)s

Summary A novel synthetic method for the preparation of high molecular weight aromatic poly- (etherketone)s is described. N-Alkyl(4-N,N-dialkylamino)pyridinium chlorides 1, 2 and 3 were used as phase-transfer catalysts in polycondensation reactions of 1,4-bis(4-chlorobenzoyl)benzene (4) with aromatic diphenols via nucleophilic displacement. The polycondensations were significantly promoted and, moreover, the results achieved in terms of molecular weight and reaction time were comparable to polymerizations conducted with 1,4-bis(4-fluorobenzoyl)benzene (5), which is a considerably more reactive monomer.     

Study on synthesis of novel soluble aromatic polyamides with pendant cyano groups

A series of novel soluble aromatic polyamides with pendant cyano groups were synthesized by low temperature polycondensation of aromatic diamines with a new monomer 2,6-bis(4-chloroformylphenoxy)benzonitrile (ClPOBN) in the presence of N,N-dimethylacetamide (DMAC) as the solvent and tertiary amines as the absorbent of HCl. The properties and structures of obtained polymers were characterized by means of FTIR, TG, and elemental analysis. Structures of prepared polymers are as expected. TG studies show that the polymers had excellent thermal stability as measured by 5% weight loss temperatures in nitrogen (409–438 °C).They are soluble in aprotic polar organic solvents such as N-methyl pyrrolidone (NMP), dimethyl sulphoxide (DMSO) and N,N-dimethylformamides (DMF) and are swelled in common solvents, such as CHCl_3, ethylene dichloride (DCE), CH₂Cl₂, tetrahydrofuran (THF), etc. Their thin films which cast from DMF had tensile strength of 79–93 MPa, Young’s moduli of 1.7–2.6 GP, elongation at break of 9–15%, indicating they are strong in mechanical properties.     

Synthesis and Characterization of processable heat resistant poly (amide-imides) for high temperature applications

Summary A series of new polyamide-imides with high thermal stability were synthesized by direct polycondensation of imide containing diamines with various aromatic diacids using polar aprotic solvents. In this technique triphenylphosphite (TPP) and pyridine were used as condensing agents to form polyamide-imide through N-phosphonium salts of pyridine. The various imide containing diamines were prepared by reacting dianhydride (PMDA, BPTDA) with aromatic diamines such as phenylene diamine, 3,3’-dichloro 4,4’-diaminodiphenylmethane and 2,6-diaminopyridine in 1:2 ratio. The diacids containing flexible ether units were prepared by treating diol with aromatic acid (2,4-dichlorobenzoic acid). The polyamide-imides obtained by this technique were characterized by elemental analysis, FTIR and ¹H-NMR. The solubility of these polyamide-imides was found to be good in polar aprotic solvents such as NMP, DMF, and DMAc etc. The viscosity of the polyamide-imides were determined and found to be in the range of 1.21 to 1.76 dl/g indicating the formation of high molecular weight polymers. The thermal stability of the polymers was tested using DSC and the Tg values are in the range of 207–234 °C showing the high thermal stability of the prepared polymers.     

Synthesis and characterization of new alkali-soluble polyimides and preparation of alternating multilayer nano-films therefrom

New alkali-soluble aromatic polyimides were prepared by a direct one-step polycondensation of 3,6-di(4-carboxyphenyl)pyromellitic dianhydride with common aromatic diamines in the presence of isoquinoline at 170 °C. The obtained polymers with inherent viscosities of the 0.62-1.01 g/dl range were all amorphous and highly soluble in dilute aqueous NaOH and tetramethylammonium hydroxide. Upon heating in TGA, the carboxylic acid groups degraded away at lower temperatures and the chain backbone did at higher temperatures. In DSC, no glass transition could be detected before decomposition. The alternating multilayer nano-films from the polyimides and poly(ethyleneimine) were prepared by the molecular self-assembly method and characterized by ellipsometry and X-ray reflectivity.     

Synthesis and properties of novel soluble fluorinated aromatic polyamides containing 4-benzoyl-2,3,5,6-tetrafluorophenoxy pendant groups

A new diaroyl chloride monomer, 5-(4-benzoyl-2,3,5,6-tetrafluorophenoxy)isophthaloyl dichloride (BTFPIPC), was prepared in a three-step synthesis. Six novel aromatic polyamides containing 4-benzoyl-2,3,5,6-tetrafluorophenoxy pendant groups were synthesized by low temperature polycondensation of BTFPIPC with six aromatic diamines in N,N-dimethylacetamide (DMAc). All these new polymers are amorphous and readily soluble in various dipolar solvents such as DMAc, N-methyl-2-pyrrolidinone (NMP), N,N-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO) at room temperature. These polymers showed glass transition temperatures between 212 and 243 °C and 5% weight loss temperatures ranging from 439 °C to 456 °C. These polyamides could be cast into transparent, flexible and strong films from DMAc solution with tensile strengths of 73.5–85.4 MPa, tensile moduli of 2.06–2.72 GPa, and elongations at break of 6.4–9.3%. These new polyamide films exhibited low dielectric constants of 3.26–3.57 (1 MHz), lower water uptakes in the range of 1.27–2.28%, and excellent transparency with an ultraviolet-visible absorption cut-off wavelength in the 326–373 nm range. Primary characterization of these new polyamides shows that they might serve as new candidates for processable high-performance polymeric materials.     

Synthesis and characterization of new rigid‐rod and organosoluble poly(amide–imide)s based on 1,4‐bis(trimellitimido)‐2,3,5,6‐tetramethylbenzene

A series of new aromatic poly(amide–imide)s (PAIs) was synthesized by triphenyl phosphite‐activated polycondensation of the diimide–diacid, 1,4‐bis(trimellitimido)‐2,3,5,6‐tetramethylbenzene (I), with various aromatic diamines in a medium consisting of N‐methyl‐2‐pyrrolidone (NMP), pyridine, and calcium chloride. The PAIs had inherent viscosities of 0.82–2.43 dL/g. The diimide–diacid monomer (I) was prepared from 2,3,5,6‐tetramethyl‐p‐phenylenediamine with trimellitic anhydride (TMA). Most of the resulting polymers showed an amorphous nature and were readily soluble in a variety of organic solvents including NMP, N,N‐dimethylacetamide (DMAc), and N,N‐dimethylformamide (DMF). Transparent, flexible, and tough films of these polymers could be cast from DMAc solutions. Their cast films had tensile strengths ranging from 80 to 95 MPa, elongation at break from 10 to 45%, and initial modulus from 2.01 to 2.50 GPa. The 10% weight loss temperatures of these polymers were above 510°C in nitrogen. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1162–1170, 2000     

Synthesis and properties of novel soluble aromatic polyamides containing 4-aryl-2,6-diphenylpyridine moieties and pendant fluorinated phenoxy groups

Three diamine monomers containing pyridine groups were prepared via the modified Chichibabin reaction of aromatic aldehydes with 4′-nitroacetophenone, followed by reduction with hydrazine hydrate in the presence of Pd/C. Novel aromatic polyamides containing 4-aryl-2,6-diphenylpyridine moieties and pendant fluorinated phenoxy groups were synthesized from these diamines and two fluorinated isophthaloyl dichlorides by the low temperature solution polycondensation in N,N-dimethylacetamide (DMAc). All the polymers are amorphous and readily soluble in strong polar organic solvents such as DMAc, N-methyl-2-pyrrolidinone (NMP), N,N-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO) at room temperature. The resulting polymers showed glass transition temperatures between 270 and 314 °C and 5 % weight loss temperatures ranging from 442 °C to 475 °C, and char yields at 800 °C higher than 53 % in nitrogen. These polyamides could be cast into transparent, flexible and strong films from DMAc solution with tensile strengths of 72.5–87.3 MPa, tensile moduli of 2.35–2.87 GPa, and elongations at break of 5.3–9.5 %. The polyamide films exhibited low dielectric constants of 3.21–3.54 (1 MHz), low water uptakes in the range of 1.17–1.38 %, and high transparency with an ultraviolet-visible absorption cut-off wavelength in the 380–391 nm range.     

Synthesis and Properties of Soluble and Light-Colored Poly(amide-imide-imide)s Based on Tetraimide-Dicarboxylic Acid Condensed from 4,4'-Oxydiphthalic Anhydride, 2,2-Bis[4-(4-aminophenoxy)phenyl]sulfone, and m-Aminobenzoic Acid, and Various Aromatic Diamines

A new-type of tetraimide-dicarboxylic acid (I) was synthesized starting from the ring-opening addition of m-aminobenzoic acid (m-ABA), 4,4'-oxydiphthalic anhydride (ODPA), and 2,2-bis[4-(4-aminophenoxy)phenyl]sulfone (BAPS) at a 2:2:1 molar ratio in N-methyl-2-pyrrolidone (NMP), followed by cyclodehydration to the diacid I. A series of soluble and light-colored poly(amide-imide-imide)s (III _a-j) was prepared by triphenyl phosphite-activated polycondensation from the tetraimide-diacid I with various aromatic diamines (II _a-j). All films cast from DMAc had cutoff wavelengths shorter than 390 nm (379–390 nm) and had b ^* values between 24.17–35.50; these polymers were much lighter in color than those of the alternating trimellitimide series. All of the polymers were readily soluble in a variety of organic solvents such as NMP, N,N-dimethyl acetamide, N,N-dimethylformamide, dimethyl sulfoxide, and even in less polar m-cresol and pyridine. Polymers III _a-j afforded tough, transparent, and flexible films, which had a strength at break ranging from 93 to 118 MPa, elongation at break from 8 to 11%, and initial modulus from 2.2 to 2.8 GPa, and some films showed yield points in the range of 95–111 MPa at stress–strain curves. The glass transition temperature of the polymers was recorded at 240–268°C. They had 10% weight loss at a temperature above 540°C and left more than 55% residue even at 800°C in nitrogen.     

Synthesis and photophysical properties of novel organo-soluble polyarylates bearing triphenylamine moieties

Two series of new blue photoluminescent aromatic polyesters (polyarylates) were synthesized from 4,4′-dicarboxytriphenylamine and 4,4′-dicarboxy-4″-methyltriphenylamine with various bisphenols by the diphenylchlorophosphate (DPCP) activated direct polycondensation in a medium of pyridine and lithium chloride. These polymers were amorphous and readily soluble in various common organic solvents including DMAc, THF, and chloroform, and could be cast from their chloroform solutions into transparent films due to their excellent solubility. These polyarylates exhibited moderately high T _g values (186–264 °C) and thermal stability. In THF solution, these triphenylamine-containing polyarylates showed UV-Vis absorption bands at 359–365 nm and photoluminescence peaks around 427–451 nm in the blue region. Figure Two series of new blue photoluminescent aromatic polyesters (polyarylates) were synthesized from 4,4’-dicarboxytriphenylamine and 4,4’-dicarboxy-4”-methyltriphenylamine with various bisphenols by the diphenylchlorophosphate (DPCP) activated direct polycondensation in a medium of pyridine and lithium chloride. These polymers were amorphous and readily soluble in various common organic solvents including DMAc, THF, and chloroform, and could be cast from their chloroform solutions into transparent films due to their excellent solubility. These polyarylates exhibited moderately high Tg values (186-264 oC) and thermal stability. All the PL spectra of these polymers showed a blue shift when the solvent was changed from NMP to THF or chloroform. Solvation should increase the interaction between polymer chain and solvent, which may consume certain excitation energy and lead to increase on the emission wavelength.     

Polyimides from a Novel Monomer 3,6-Bis(dimethylamino)acridine(p-cymene)dichlororuthenium(II) for a Catalytic Application

Tricyclic heteroaraomatic dye-based monomer containing NMe₂ units, 6-bis(dimethylamino)acridine(p-cymene)dichlororuthenium (II), was used to prepare novel polyimides via a one-stage solution polycondensation due to their stability under a variety of oxidative and reductive conditions. The Ru(II) complex monomer was synthesized starting from [RuCl₂(p-cymene)]₂ and 3,6-bis(dimethylamino)acridine. A series of stable polyimides was synthesized from the Ru(II) complex of 3,6-bis(dimethylamino)acridine and various aromatic dianhyrides. The polymers had inherent viscosities ranging from 1.72 to 2.11 dL/g and were soluble in polar solvents. The glass transition temperatures were 192–278 °C, and the 10% weight loss temperatures were above 503–635 °C. Ruthenium-substituted polyimides were tested for catalytic activity in the furan formation reaction of (Z)-3-methylpent-2-en-4-yn-1-ol. The polymeric catalyst was added to (Z)-3-methylpent-2-en-4-yn-l-ol without a solvent and the pure furan was isolated by distillation under reduced pressure. The conversion of the starting, enynol, was determined by gas chromatography (GC).