Preparation of polyamide-imides via the phosphorylation reaction. II. Synthesis of wholly aromatic polyamide-imides from N-[p-(or m-) carboxyphenyl]trimellitimides and various aromatic diamines

Wholly aromatic polyamide-imides with high molecular weight (η_inh up to 1.7 dL/g in DMAc–5% LiCl) were obtained by the direct polycondensation reaction of N-[p-( or m-) carboxyphenyl]trimellitimide [p-(or m-)CPTMI] and aromatic diamines by means of di- or triphenyl phosphite in N-methyl-2-pyrrolidone (NMP)-pyridine solution in the presence of lithium or calcium chloride. The factors affecting the phosphorylation reaction were investigated, in particular for the reaction of p-CPTMI and 4,4'-oxydianiline (ODA). Molecular weight of polymers varied with the amount of metal salts and showed maximum values at the concentration of 10-15 wt % in the reaction mixture. Monomer concentration of 0.2 mol/L produced polymer of the highest viscosity. Higher concentrations produced gelation and yielded polymers of low molecular weight. A reaction temperature of about 120°C gave the best results. Among the solvents tested, NMP was significantly the most effective for the reaction. The highest inherent viscosity values, η_inh = 1.35 and 1.58 dL/g, were obtained with triphenyl phosphite (TPP)/monomer and diphenyl phosphite (DPP)/monomer molar ratios of 2.0. Excessive addition of phosphites did not cause a serious deleterious effect on the molecular weight of polymer. Polycondensations of several combinations of p-or m-CPTMI and aromatic diamines were carried out with satisfactory results.     

Wholly aromatic polyamides by the direct polycondensation reaction using triphenyl phosphite in the presence of poly(4-vinylpyridine)

The polycondensation reaction of aromatic dicarboxylic acids and diamines by using triphenyl phosphite were carried out in N-methylpyrrolidone (NMP) in the presence of poly(4-vinylpyridine) (P4VP). The reaction, especially of terephthalic acid (TPA), was markedly facilitated to give the absence of P4VP. The reaction promoted by P4VP was further favored by the addition of various pyridine derivatives; of the pyridines examined, pyridine was most effective, giving the best results at a high level (pyridine/P4VP values up to 26). P4VP of the molecular weight in the range of 1.3 × 10⁴?3.0 × 10⁵ did not affect the viscosity of the resulting polymer. These favorable additive effects of P4VP on the reaction of TPA were not observed in the reactions of isophthalic acid, and m -and p-aminobenzoic acids.     

High-molecular-weight polyterephthalamide by direct polycondensation reaction in the presence of poly(ethylene oxide)

Polyterephthalamides of high molecular weight (η_inh up to 1.9) were obtained by the direct polycondensation reaction of terephthalic acid and aromatic diamines in the presence of poly(ethylene oxide) (PEO) with triphenyl phosphite in a N-methylpyrrolidone (NMP)–pyridine solution that contained lithium chloride. The molecular weights of the polymers produced varied with the amount and molecular weight of PEO, which showed maximum values when PEO with a molecular weight of 2.0 × 10⁴?5.0 × 10⁵ was used in a concentration of about 0.5 wt % in the solvent. The polycondensation reaction was significantly affected by the level of pyridine in a mixed solvent of NMP and pyridine and by the concentration of the lithium chloride added.     

Synthesis and properties of polyamides of 3,3′-dimethylnaphthidine and its model compounds

A number of polyamides and model amides based on 3,3′-dimethylnaphthidine and various dicarboxylic acids were synthesized in N-methylpyrrolidone containing lithium chloride either by low temperature solution or by direct polycondensation using triphenyl phosphite and pyridine. The polyamides had inherent viscosities of 0.36?5.42 dL g^?1 and were, in general, readily soluble in N-methylpyrrolidone. Amorphous members exhibited relatively high glass transition temperatures in the range of 340–380 and 200–230°C for aromatic and aliphatic polymers, respectively. All polyamides showed good thermal stability in nitrogen and in air.     

High-molecular-weight poly(amino acid)s by the direct polycondensation reaction promoted by triphenyl phosphite and LiCl in the presence of polyvinylpyrrolidone

Poly(α-amino acid)s of high molecular weight were obtained by the direct polycondensation reaction of α-amino acids in the presence of polyvinylpyrrolidone (PVP) as a matrix of triphenyl phosphite and LiCl in N-methylpyrrolidone (NMP). Molecular weights of the polymer produced were improved by use of an increasing amount of matrix of higher molecular weight. Most favorable results were obtained by the reaction at 80°C for 16 hr at a monomer concentration of 0.33 mole/liter in a NMP solution that contained about 3 wt % LiCl in the presence of an equivalent unit mole of PVP with the molecular weight of 3.6 x 10⁵. The polymer from β-alanine with high molecular weight, which is difficult to obtain by the NCA method, was easily prepared by this process.     

Synthesis and properties of aliphatic-aromatic poly(amide-imide)s from sulfonyldianilines and N,N′-bis(ω-carboxyalkyl)pyromellitimides

Seven imide-containing dicarboxylic acids IIa-g were synthesized from pyromellitic dianhydride and amino acids of the formula HOOC—(CH₂)_m—NH₂, with m—1,2,3,4,5,10,11. These diacids were condensed directly with 3,3′- or 4,4′-sulfonyldianiline using triphenyl phosphite in N-methyl-2-pyrrolidone (NMP)-pyridine solution containing calcium chloride and lithium chloride. The resulting poly(amide-imide)s have moderate to high inherent viscosities ranging from 0.47 to 2.02 dL/g in dimethylacetamide. These polymers showed excellent solubility in polar solvents such as NMP, and most of them could be cast into transparent and tough films. Glass transition temperatures (T_gs) of these poly(amide-imide)s were recorded in the range 116–258°C and increased with decreasing number of methylene groups in the repeated unit. The polymers with longer aliphatic chains (e.g., m = 10 and 11) exhibited higher crystallinity, higher initial decomposition temperature, and lower solubility in polar solvents.     

Studies on reactions of the N-phosphonium salts of pyridines—VII : Preparation of peptides and active esters of amino acids by means of diphenyl and triphenyl phosphites in the presence of tertiary amines

Peptides and active esters of amino acids were produced in high yields from carboxyl and amino or hydroxyl components in pyridine with an equivalent amount of diphenyl phosphite or half an equivalent amount of triphenyl phosphite and tertiary amines. Condensation reactions competed with the reaction with a phenoxy group of the phosphite to produce the phenyl ester and were governed by the tertiary amine employed in the reaction. The reactions are assumed to proceed via the N- phosphonium salts of pyridines, similar to those obtained by the oxidation of phosphorus compounds with mercuric salts in pyridine.     

Effects of substituted triphenyl phosphites on the radical polymerization of acrylonitrile

The radical polymerization of acrylonitrile in the presence of nuclear-substituted triphenyl phosphites (p-Cl, H, p-CH₃, p-OCH₃) initiated by α,α′-azobisisobutyronitrile at 50°C was investigated. It was found that the rate of polymerization decreased at low concentrations of phosphite, but after reaching a minimum the rate increased again with further increase in the phosphite concentration in the case of all substituted triphenyl phosphites. Formation of a weak complex between phosphite as donor and acrylonitrile as acceptor was confirmed from the change in chemical shifts of vinyl protons to higher magnetic fields on NMR spectroscopy. From the results of continuous variation method using NMR spectra, the complex was found to be of the 1:1 type. The effects of substituted triphenyl phosphite on the rate of polymerization and the chain-transfer reaction to substituted triphenyl phosphites are discussed on the basis of these results.     

Synthesis of 4H-3,1-benzoxazin-4-ones and 4-(3H)quinazolinones from anthranilic acids and their derivatives by the use of triphenyl phosphite and pyridine

A series of 2-substituted 4H-3,1-benzoxazinones and 2,3-disubstituted 4-(3H)quinazolinones have been synthesized in mild conditions by the use of triphenyl phosphite and pyridine as cyclising medium. Benzox-azinones are produced either by ring closure of 2-(acylamino)benzoic acids or in the reaction of benzoic acid with anthranilic acids. In the presence of aniline, the reaction leads to quinazolinones.     

Synthesis of Diphenyl α-（Dipropoxyphosphoramido）alkyl-phosphonates

A convenient method has been developed for the synthesis of diphenyl α-（dipropoxyphosphoramido）alkyl- phosphonates under mild conditions, namely the reaction of dipropyl phosphoramidate （1） with a para（un）substituted benzaldehyde or cyclicketone （2） and triphenyl phosphite （3） by a one-pot procedure with the aid of acetyl chloride.     

Photopolymerization of acrylonitrile in the presence of substituted triphenyl phosphites

It was found that acrylonitrile was polymerized at 30°C by ultraviolet irradiation in the presence of triphenyl phosphite and its derivatives, namely m-CH₃, p-C₂H₅, and p-CH₃ substituted triphenyl phosphites under conditions where acrylonitrile alone did not polymerize and phosphites did not undergo photolysis. The rate of polymerization in the presence of triphenyl phosphite and tri-p-tolyl phosphite was found to be proportional to the monomer concentration, the phosphite concentration, and the light intensity. From these results, it was thought that a donor–acceptor complex formed between phosphite and acrylonitrile which absorbed light and initiated the radical polymerization. In the photopolymerization of acrylonitrile with substituted triphenyl phosphites, the rate of polymerization increased with an increase in electron-donating ability of substituent. From the plot obtained by use of Hammett's equation (log R_p/R_p0 = ρσ), the ρ value was found to be ?1.0.     

Preparation of sulfonyl aromatic polyamides and copolyamides by means of di- or triphenyl phosphite

High molecular-weight aromatic polyamides were obtained by the direct polycondensation reaction of 4,4′-sulfonyldibenzoic acid (SDA) with various aromatic diamines, by means of di- (DPP) or triphenyl phosphite (TPP) in N-methyl-2-pyrrolidone (NMP)-pyridine solution containing metal salts such as LiCl and CaCl₂. The factors affecting the phosphorylation reaction were investigated, in particular for the reaction of SDA and 4,4′-oxydianiline (ODA). For the polymerization by means of TPP, the optimum conditions are: molar ratio of TPP to diacid, higher than 2.3; concentration of metal salts, 8 wt % LiCl or 6 wt % CaCl₂; reaction temperature, 100°C; and monomer concentration, 0.4 mol/L. For the polymerization by means of DPP, the optimum conditions are: molar ratio of DPP to diacid, higher than 3.8; concentration of metal salts of 8 wt % LiCl or 10 wt % CaCl₂; reaction temperature, 110°C; and monomer concentration, 0.4 mol/L. Copolyamides were also prepared from the reaction of ODA with the mixed diacids of SDA and other dicarboxylic acids such as terephthalic acid, isophthalic acid, and 2,6-naphthalene dicarboxylic acid by using TPP and DPP as the condensing agents.     

Preparation of polymide-imides by direct polycondensation with triphenyl phosphite. V. Aliphatic-aromatic polyamide-imides based on N,N′-bis(ω-carboxyalkyl) benzophenone-3,3′,4,4′-tetracarboxylic diimides

Five diimide-dicarboxylic acids were prepared from benzophenone-3,3′,4,4′-tetracarboxylic dianhydride and glycine, β-analine, 4-aminobutyric acid, 6-aminocaproic acid, and 11-aminoundecanoic acid. New aromatic-aliphatic polyamide-imides were prepared by the direct polycondensation of these diacids with aromatic diamines using triphenyl phosphite in N-methyl-2-pyrrolidone (NMP)–Pyridine solution in the presence of calcium chloride. The resulting polymers were characterized by inherent viscosity, infrared spectra, elemental analyses, solubility, differential scanning calorimetry (DSC), thermogravimetry, and wideangle x-ray diffraction measurements.     

Reaction of N-(Trichloroacetyl)trichloroacetimidoyl Chloride with Phosphites

N-(Trichloroacetyl)trichloroacetylimidoyl chloride reacts with trialkyl phosphites with substitution of the imidoyl chlorine atom and formation of C-phosphorylated heterodienes. The reaction with triphenyl phosphite or o-phenylene diethylphosphoroamidite proceeds as [4+1]-cycloaddition to give mono- or spirocyclic oxazaphospholines with the five-coordinate phosphorus atom. Dialkyl or diphenyl hydrogen phosphites add across the C = N bond of imidoyl chloride to give labile N-(-phosphorylated) trichloroacetamides.     

Pentaatomie heteroaromatic cations. Note III . A Convenient Synthesis of Aldehydes from Carboxylic Acids via 2-Substituted 1,3-Benzoxathiolium Perchlorates

A convenient method for the preparation of aldehydes from the corresponding carboxylic acids is presented. By reaction of the carboxylic acids with o-mercaptophenol and perchloric acid in phosphorus oxychloride, the corresponding 2-substituted 1,3-benzoxathiolium perehlorates were obtained. Reduction of the salts with lithium aluminium hydride in dry ether gave 2-substituted 1,3-benzoxathioles, which, when hydrolyzed by mercuric chloride, gave the corresponding aldehydes. Twenty five aldehydes of different structure were obtained in good yields, by a fast and simple procedure.     

New optically active poly(amide–imide)s from N-trimellitylimido-l-amino acid and 1,2-bis[4-aminophenoxy]ethane in the main chain: Synthesis and characterization

Six new optically active poly(amide–imide)s (PAIs) with good inherent viscosities were synthesized from the direct polycondensation reaction of N-trimellitylimido-l-amino acids with 1,2-bis[4-aminophenoxy]ethane by direct polycondensation in a medium consisting of N-methyl-2-pyrrolidone (NMP)/triphenyl phosphite (TPP)/calcium chloride (CaCl₂)/pyridine (py). Diamine was synthesized by using a two-step reaction. At first 1,2-bis[4-nitrophenoxy]ethane was prepared from the reaction of two equimolars 4-nitrophenol and one equimolar 1,2-dibromo ethane and the dinitro compound was reduced by using Pd/C. Also N-trimellitylimido-l-amino acids were synthesized by the condensation reaction of trimellitic anhydride with two equimolars of various l-amino acids in acetic acid solution. The polymerization reactions produced a series of optically active PAIs with a high yield and good inherent viscosity. The resulted polymers were fully characterized by means of FTIR and ¹H NMR spectroscopy, elemental analyses, inherent viscosity, specific rotation, solubility tests, thermogravimetric analysis (TGA), and a derivative of thermogravimetric (DTG) analysis.     

Direct polyesterification promoted by a complex of phosphorus oxychloride with LiCl monohydrate

The reaction of benzoic acid and p-chlorophenol with phosphorus oxychloride (POC) was significantly affected by the presence of metal salt hydrates or a mixture of metal salts and water sufficiently aged. Among metal salts examined, LiCl was most effective for the reaction to give quantitative yield of the benzoate. The reaction was assumed to proceed via a complexation of POC with LiCl monohydrate followed by selective hydrolysis of POC by water bound to LiCl. The reaction promoted by a complex derived from POC and LiCl monohydrate in pyridine was successfully used as a new condensing agent for the synthesis of aromatic polyesters by the direct polycondensation or aromatic dicarboxylic acids and bisphenols. Under favorable conditions for aging of POC with LiCl monohydrate and for addition of bisphenols, polymers of moderate to high molecular weights were obtained in quantitative yield. The reaction was applied with limited success to the preparation of a copolymer of high molecular weight from hydroxybenzoic acids.     

Polyureas from carbon dioxide and diamines by means of triphenyl phosphite and pyridine hydrochloride

The reaction of carbon dioxide with aniline using triphenyl phosphite in pyridine is greatly facilitated by the addition of hydrochlorides of tertiary amines such as pyridine and triethylamine, and has been successfully applied to the preparation of polyureas of high molecular weight from carbon dioxide and aromatic diamines. The presence of a catalytic amount of pyridine hydrochloride significantly increased the inherent viscosity of the resulting polymers, the highest value being obtained with about an equivalent of the chloride. Optimal temperatures and pressures varied with diamines used, and were 60–80°C and 40–50 atm of carbon dioxide. The polycondensation reaction was also affected by the solvent compositions of pyridine and N-methylpyrrolidone, its optimum being dependent on diamines used.     

Synthesis and properties of novel aromatic polyamides based on “multi-ring” flexible dicarboxylic acids

The five benzene rings-containing (hereafter referred to as “five-ring”) dicarboxylic acids α,α′-bis[4-(4-carboxyphenoxy)phenyl]-1,4-diisopropylbenzene (p- III ) and α,α′-bis[4-(4-carboxyphenoxy)phenyl]-1,3-diisopropylbenzene (m- III ) were prepared by the fluoro-displacement of α,α′-bis(4-hydroxyphenyl)-1,4-diisopropylbenzene and α,α′-bis(4-hydroxyphenyl)-1,3-diisopropylbenzene with p-fluorobenzonitrile, and subsequent alkaline hydrolysis of the intermediate dinitriles. A number of high-molecular-weight polyamides based on these two “five-ring” dicarboxylic acids (p- III and m- III ) and various aromatic diamines were directly synthesized in N-methyl-2-pyrrolidone (NMP) containing lithium chloride (LiCl) or calcium chloride (CaCl₂) using triphenyl phosphite and pyridine as condensing agents. These polyamides were obtained with inherent viscosities above 0.51 and up to 0.91 dL/g. The weight-average molecular weight were in the range of 51,000–211,000. Most of these polyamides were amorphous and readily soluble in polar solvents such as NMP, N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), and dimethyl sulfoxide (DMSO), and afforded tough, flexible, and transparent films by solution-casting. The films had tensile strength of 50–83 MPa, elongation to break of 4–8%, and tensile modulus of 1.3–2.0 GPa. Most polyamides showed distinct glass transitions on the differential scanning calorimetry (DSC) curves ranging from 147 to 177°C. In nitrogen or air, all the polymers showed no significant weight loss up to 490°C, as indicated by thermogravimetric analysis (TG). © 1996 John Wiley & Sons, Inc.     

Cloud Points of Water—soluble Polyether Phosphites and Their Application in the Biphasic Hydroformylation of Higher Olefins

Wate-soluble polyether phosphites alkyl polyethylene glycol ophenylene phosphite(APGPPS)were alcoholysis of phosphorus chloride with plyoxyethylene alkyl ether.With appropriate HLB(hydrophile-lypophile balance),the phosphites possess clear cloud points below 100℃，Addition of some inorganic salts decreases cloud points of the phosphites.When the phosphiites have long polyether chain binding to short-chain alkyl group,their cloud points could be extrapolated from figure of dependece of cloud points on addition of inorganic salts.Utilizing octylpolyglycol-phenylene-phosphite(OPGPP)(APGPP,R:Octyl)/Rh complex formed in situ as catalyst,over 90% conversion of 1-decene was obtained ,avoiding the limitation of water insolubility of substrates.Preliminary results indicated that micellar catalysis and thermoregulated phase-transfer catalysis(TRPTC)coexist in the reaction system.Below cloud point,micellar catalysis induced by plyether phosphites may be existed.When temperature is increased to above cloud point of the phosphies,this reaction works mainly in TRPTC.The catalysts could be easily spearated by simple decantation,but followed by considerable loss in activity after three successive reaction runs.Preliminary results indicated hydrolysis of OPGPP happened during the reaction.which may explain for the bad loss in activity.The catalyst was reused up to seven times with-out clear decrease in activity when OPGPP/Rh ratio was increased to 50.