Presence Of Triphenyl Phosphite Research Articles

Superior ductile poly(glycolic acid)/poly(butylene adipate-co-terephthalate) blends compatibilized by triphenyl phosphite

Present study was aimed at exploring the compatibilization of poly(glycolic acid)/ poly(butylene adipate-co-terephthalate) (PGA/PBAT) blend in the presence of triphenyl phosphite (TPP) to prepare the ductile blend. The chain extension was monitored by the change torque value, which consisted with rheological behavior, that is, the increased TPP content led to an enhancement of melt strength for PGA/PBAT. TPP acted as a bridge to generate PGA-g-PBAT copolymer, promoting the interfacial interaction and miscibility of polymers. After being reactively compatibilized by 3 wt% TPP, the elongation at break, notched impact strength, and fracture toughness of the modified blend were increased by 627%, 60%, and 583% respectively. The morphology of impact-fractured surface revealed that the size of PBAT particles decreased from 2.05 µm to 1.35 µm with 3 wt% of TPP. The compatibilized blend with ductile feature was attributed to the interfacial debonding appending the fibrillation. Furthermore, when the content of TPP reached 5 wt%, the promoted chain entanglement led to a reduction of ductility. This work provided a facile strategy for the preparation of ductile PGA/PBAT blend.

Synthesis of polyamids from some of the medical drugs after the Insertion of 1,3,4-thiadiazole ring in their composition

This search include preparation of polyamids Containing some of the medical drugs, by the polycondensathion method for amino-1,3,4-thiadiazole compounds with dicarboxylic acids (terephthalic acid and phthalic acid) in presence of triphenyl phosphite and by using domestic microwave oven. Electrical conductivity were determined by using electrical conductivity cell unit.
 The prepared compounds were characterized by UV/Vis (Ultraviolet/visible), IR (Infra-red) and 1H-NMR (Proton nuclear magnetic resonance) spectra in (d6-DMSO) Solvent ,in addition to using elemental analyses apparatus (C.H.N) for some prepared compounds.

Phosphorylation‐assisted synthesis and characterization of poly(3,4'‐oxydiphenylene furanamide) as a wholly aromatic polyamide using biomass‐derived 2,5‐furandicarboxylic acid

AbstractWe report the phosphorylation‐assisted polymerization and characterization of 2,5‐furandicarboxylic acid (FDCA)‐based wholly aromatic polyamide. For this purpose, poly(3,4′‐oxydiphenylene furanamide) (PODFA) was synthesized via solution polymerization of FDCA with 3,4′‐oxydiphenylamine (ODPA) in the presence of triphenyl phosphite and pyridine. The spectroscopic analyses and solution viscosity measurement revealed the successful synthesis of a relatively high molecular weight PODFA with good solubility in a variety of polar aprotic solvents without inorganic salts. PODFA could be thus processed into purely amorphous films with high flexibility in bending and folding deformation. The 39 μm thick PODFA film exhibited optical transparency, and the 65–100 μm thick films showed a transparent yellow or light brown color. The amorphous PODFA films were characterized to have excellent thermal and static mechanical properties in terms of a glass transition temperature of ~260°C, a thermal decomposition peak temperature of ~450°C, a residue of ~50% at 800°C under nitrogen gas condition, an initial modulus of 12.98 ± 1.84 GPa, a tensile strength of 84.6 ± 17.3 MPa, and a strain at break of 2.3 ± 1.5% at room temperature.

Ionic liquid mediated synthesis of 4, 4'diamino azo benzene substituted aliphatic polyamides and thermal studies

Ionic liquids act as green solvents, which can replace the usual traditional solvents which pose both environmental and biological hazard. In the present work 4,4'diamino azobenzene has been condensed with various aliphatic diacids such as succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid and Pimelic acid using imidazolium based ionic liquids in the presence of triphenylphosphite(TPP). The resulting azopolyamides have been obtained in high yield with intrinsic viscosity ranging from 0.56 - 0.81 dlg-1. This method is compared with modified Higashi’s method. The thermodynamic parameters like G, H and S are calculated by approximate methods such as Freeman & Carroll, Coats & Red fern, Doyle and Murray and White. The resulting polyamides prepared using green condition show increased thermal stability when compared to polyamides prepared by modified Higashi’s method.

Synthesis of C-β-d-glucopyranosyl derivatives of some fused azoles for the inhibition of glycogen phosphorylase

Annulated C-β-d-glucopyranosyl heterocycles were synthesized and tested as inhibitors of glycogen phosphorylase. 2-(β-d-Glucopyranosyl)-1H-imidazo[4,5-b]pyridine was formed by ring-closure of O-perbenzoylated C-β-d-glucopyranosyl formic acid with 2,3-diaminopyridine in the presence of triphenylphosphite. Cyclisations of bromomethyl 2,3,4,6-tetra-O-benzoyl-β-d-glucopyranosyl ketone with a set of 2-aminoheterocycles resulted in constitutionally reversed C-β-d-glucopyranosyl imidazoles fused by pyridine, pyrimidine, thiazole, 1,3,4-thiadiazole, benzothiazole and benzimidazole. O-Debenzoylation of the above compounds was effected by standard transesterification to get the test compounds. The 1H-imidazo[4,5-b]pyridine proved to be a low micromolar inhibitor (Ki = 21.1 μM) of rabbit muscle glycogen phosphorylase b, while the other heterocycles displayed weak or no inhibition against the same enzyme.

Synthesis and characterization of poly(amide-imide)s derived from a new ortho-functional unsymmetrical dicarboxylic acid

Herein, we report a new diacid monomer containing an imide ring and a methoxy pendant group, 3-trimellitimido-4-methoxybenzoic acid TMBA, for the preparation of poly(amide-imide)s.

Silicon-containing poly(amide-imide)s: preparation, characterization, and properties

Reactions of 3-aminophenol with dichlorodiphenylsilane in the presence of triethylamine resulted in the preparation of a diamine named as bis(m-aminophenoxy)diphenylsilane. Reaction of the diamine with two moles of trimellitic anhydride led to the preparation of a diacid with preformed imide structures. Silicon-containing poly(amide-imide)s were then prepared by polycondensation reactions of the diacid with different diamines in the presence of triphenyl phosphite. All the products and polymers were characterized and the physical properties of the polymers including solubility, solution viscosity, thermal stability, thermal behavior, flameretardency, crystallinity, and morphology were studied. The polymers showed high thermal stability and flameretardency, as well as enhanced solubility in polar solvents. The glass transition temperature of the polymers was about 187–196 °C, the temperature for 10% gravimetric loss was in the range of 375–400 °C, and also the weight of the polymer remaining at 700 °C was about 39–44%. They were flame-retardant, soluble in dipolar aprotic solvents, and showed some crystalline structures.

Synthesis, characterization and photo behavior of new poly(amide-imide)/ montmorillonite nanocomposite containing N,N'-pyrromellitoyl-bis-L-alanine

Two new samples of poly(amide-imide)-nanocomposites were synthesized by insertion nano silicate particles in poly(amide-imide) (PAI) chains using a convenient solution intercalation technique. PAI as a source of polymer matrix was synthesized by the direct polycondensation reaction of N,N'-pyrromelitoyl-bis-L-alanine with 4,4'-diamino diphenyl ether in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). Morphology and structure of the resulting PAI-nanocomposite films with 5 and 10% silicate particles were characterized by FTIR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposites films were investigated by using UV-Vis spectroscopy, thermogravimetric analysis (TGA) and water uptake measurements. KEY WORDS: Nanocomposite, Poly(amide-imide), Silicate particle, Polycondensation, Thermal behavior Bull. Chem. Soc. Ethiop. 2013, 27(3), 459-467.DOI: http://dx.doi.org/10.4314/bcse.v27i3.15

New thermally stable poly(amide-imide)/montmorillonite reinforced nanocomposite based on N,N′-pyrromellitoyl-bis-l-valine: synthesis and characterization

Abstract Two new samples of poly(amide-imide) (PAI)/nanocomposites reinforced montmorillonite containing N,N′-pyrromelitoyl-bis-l-valine moiety in the main chain were synthesized by a solution intercalation technique. PAI 3 as a source of polymer matrix was synthesized by the direct polycondensation reaction of N,N′-pyrromelitoyl-bis-l-valine 1 with 4,4′-diamino diphenyl ether 2 in the presence of triphenyl phosphite, CaCl2, pyridine and N-methyl-2-pyrrolidone. The morphology and structure of the resulting PAI-nanocomposite films 4a and 4b with 5% and 10% silicate particles were characterized by Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposites films were investigated by using UV-visible spectroscopy, thermogravimetric analysis and differential scanning calorimetry.

Toughening of Biodegradable Polylactide/Poly(butylene succinate-co-adipate) Blends via in Situ Reactive Compatibilization

Polylactide and poly(butylene succinate-co-adipate) (PLA/PBSA) were melt-blended in the presence of triphenyl phosphite (TPP). An increase in the torque during melt mixing was used to monitor the changes in viscosity as compatibilization of the blends occurred. Scanning electron micrographs showed not only a reduction in the dispersed-phase size with increased TPP content but also fibrillated links between the PLA and PBSA phases, signifying compatibilization. Moreover, optimization of parameters such as the mixing sequence and time, TPP content, and PBSA concentration revealed that blends containing 30 and 10 wt % PBSA and 2 wt % TPP, which were processed for 30 min, were optimal in terms of thermomechanical properties. The impact strength increased from 6 kJ/m(2) for PLA to 11 and 16 kJ/m(2) for blends containing 30 and 10 wt % PBSA, respectively, whereas the elongation-at-break increased from 6% for PLA to 20 and 37% for blends containing 30 and 10 wt % PBSA, respectively. Upon compatibilization, the failure mode shifted from the brittle fracture of PLA to ductile deformation, effected by the debonding between the two phases. With improved phase adhesion, compatibilized blends not only were toughened but also did not significantly lose tensile strength and thermal stability.

Processing of Thermally Stable Polymer Nanocomposites Reinforced Silicate Nanoparticles Based on N-trimellitylimido-L-phenyl alanine

Abstract In this article two polymer/nanocomposite films with 5 and 10% silicate particles based on Poly(amide-imide) (PAI) from N-trimellitylimido-L-phenyl alanine were prepared via solution intercalation method through blending of organoclay with the PAI solution. Poly(amide-imide) was synthesized by the direct polycondensation reaction of N-trimellitylimido-L-phenyl alanine with 4,4′-diamino diphenyl ether in the presence of triphenyl phosphite (TPP), CaCl2 and pyridine (Py). Morphology and structure of the resulting PAI-nanocomposite films were characterized by FTIR spectroscopy, X-ray diffraction and scanning electron microscopy (SEM). The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposites films were investigated by using Uv-vis spectroscopy, thermogravimetric analysis (TGA) and water uptake measurements.

Morphological and thermal properties of nanocomposites contain poly(amide-imide) reinforced with bioactive N-trimellitylimido-L-valine modified TiO2 nanoparticles

Nanoparticles (NPs), such as metal oxides, have a strong tendency to agglomerate, so homogeneous dispersion of these materials in a polymer matrix is desirable. As a result to overcome this problem and to enhance the filler-polymer interaction, it is better to functionalize the surface of NPs. In this study we describe the synthesis and characterization of novel poly(amide-imide)/TiO2 nanocomposites (PAI/TiO2 NCs). At first, the surface of TiO2 NPs was modified by N-trimellitylimido-L-valine as a bioactive coupling agent. Modification by this linker causes that, the obtained TiO2 NPs become environmentally friendly. Thereafter, NCs of modified TiO2 and PAI were synthesized by means of an ultrasonic technique. PAI as a source of polymer matrix was synthesized by direct polycondensation reaction of N-trimellitylimido-L-valine with diaminediphenylsulphone in the presence of triphenyl phosphite and the molten tetra-n-butylammonium bromide. By the insertion of surface modified TiO2 NPs into the polymer matrix, a considerable improvement of thermal property was achieved which was examined using thermogravimetric analysis. The structure and morphology of resulting NCs with 5 %, 10 % and 15 % TiO2 NPs were characterized by Fourier transform IR spectroscopy, X-ray diffraction, Field emission scanning electron microscopy and transmission electron microscopy. The optical properties of the NCs were studied using ultraviolet–visible spectroscopy.

Synthesis and characterization of new imidazole and fluorene–bisphenol based polyamides: Thermal, photophysical and antibacterial properties

A new para-linked diether-diamine, 9,9-bis{4-[2-(4,5-diphenylimidazol-2-yl)-4-aminophenoxy] phenyl}fluorene (III), bearing fluorene–bisphenol and two ortho-linked diaryl-substituted imidazole rings were synthesized by the catalytic reduction of the nitro groups of compound (II), 9,9-bis{4-[2-(4,5-diphenylimidazol-2-yl)-4-nitrophenoxy]phenyl}fluorene, by using hydrazine monohydrate in the presence of Pd/C. Compound (II) was synthesized by the nucleophilic chloro displacement reaction of the synthesized 2-(2-chloro-5-nitrophenyl)-4,5-diphenyl-1H-imidazole with 9,9-bis(4-hydroxyphenyl)fluorene in refluxing DMAc in the presence of potassium carbonate. This diamine was condensed directly with aliphatic and aromatic diacids via the Yamazaki–Higashi phosphorylation method in the presence of triphenylphosphite (TPP), pyridine (Py) and halide salt to give high molecular polyamides (PAs). The synthesized PAs were obtained in quantitative yields with inherent viscosities between 0.51 and 0.76dLg−1. The structures of diamine and PAs were characterized by elemental analysis, FT-IR and NMR spectroscopy, and properties of PAs were investigated by using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and UV–visible and fluorescence spectroscopy. The PAs showed good solubility in aprotic and polar organic solvents, with high thermal stability exhibiting the glass transition temperatures (Tgs) and 10% weight loss temperatures (T10%) in the range of 226–330°C and 400–466°C in air, respectively, and fluorescence emission with maximum wavelengths (λem) in the range of 417–473nm with quantum yields (Φf) of 9–35%. Two of these polymers together with compounds (II) and (III) were also screened for antibacterial activity against Gram positive and Gram negative bacteria.

Synthesis and characterization of thermally stable poly(amide-imide)-montmorillonite nanocomposites based on bis(4-carboxyphenyl)-N,N'-pyromellitimide acid

Two new poly(amide-imide)-montmorillonite reinforced nanocomposites containing bis(4-carboxyphenyl)-N,N'-pyromellitimide acid moiety in the main chain were synthesized by a convenient solution intercalation technique. Poly(amide-imide) (PAI) as a source of polymer matrix was synthesized by the direct polycondensation reaction of bis(4-carboxyphenyl)-N,N'-pyromellitimide acid with 4,4'-diamino diphenyl sulfone in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). Morphology and structure of the resulting PAI-nanocomposite films with 10 and 20% silicate particles were characterized by FT-IR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposites films were investigated by using UV-Vis spectroscopy, thermal gravimetry analysis (TGA) and water uptake measurements. KEYWORDS: Bis(4-carboxyphenyl)-N,N'-pyromellitimide acid moiety, Poly(amide-imide)-montmorillonite nanocomposite, Thermal properties Bull. Chem. Soc. Ethiop. 2013, 27(1), 95-104.DOI: http://dx.doi.org/10.4314/bcse.v27i1.10

New poly(ether-amide-imide) reinforced layer silicate nanocomposite: Synthesis and properties

A new series of poly(ether-amide-imide)/organoclay were generated through solution intercalation technique. Cloisite® 20A was used as a Modified montmorillonite for ample compatibilization with the PEAI matrix. The poly(ether-amide-imide) (PEAI) 3 chains were synthesized by the direct polycondensation reaction of N,N′-(4,4′-diphenylether)bistrimellitimide 1 with 4,4′-diamino diphenyl ether two in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). Morphology and structure of the resulting PEAI-nanocomposite films 3a–3b with (5–10wt%) silicate particles were characterized by FTIR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposite films were investigated by using UV–Vis spectroscopy, thermogravimetric analysis (TGA) and water uptake measurements.

Synthesis and properties of new polyamide-organoclay nanocomposites containing pyrazine moiety in the main chain

AbstractA series of polyamide (PA)/montmorillonite nanocomposites containing pyrazine moiety in the main chain were synthesized by a convenient solution intercalation technique. PA 3 as a source of polymer matrix was synthesized by the direct polycondensation reaction of pyrazine-2,3-dicarboxylic acid 1 with 4,4′-diaminodiphenyl sulfone 2 in the presence of triphenyl phosphite, CaCl2, pyridine, and N-methyl-2-pyrrolidone. The resulting nanocomposite films were characterized by Fourier transform infrared spectra, X-ray diffraction, scanning electron microscopy, and thermogravimetric analysis (TGA). The results showed that organo-modified clay was dispersed homogeneously in the PA matrix. TGA indicated an enhancement of thermal stability of new nanocomposites compared with the pure polymer.

Synthesis and characterization of novel aromatic polyamides via Yamazaki–Higashi phosphorylation method

AbstractWe synthesized four aromatic diacids: 1,3‐bis(3‐carboxyphenoxy)benzene, 1,4‐bis(4‐carboxyphenoxy)benzene, 1,4‐bis(3‐carboxyphenoxy) benzene, and 1,3‐bis(4‐carboxyphenoxy)benzene, following a procedure of a previously reported synthesis (Ueda and Komatsu, J Polym Sci Part A: Polym Chem 1989, 27, 1017). These diacids were condensed directly with aromatic diamines 4,4′‐oxydianiline (ODA), via the Yamazaki–Higashi phosphorylation method in the presence of triphenylphosphite (TPP), pyridine (Py) and halide salts to give high molecular aromatic polyamides (PAs). The synthesized PAs were obtained in quantitative yields with inherent viscosities between 0.5 and 1.0 dL g−1. The structures and properties of the obtained PAs were characterized by Fourier transform infrared (FTIR) spectra, nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), polarizing optical microscope (POM). Four PAs all showed good solubility in polar solvents, such as dimethylsulfoxide (DMSO), N,N‐dimethylacetamide (DMAc), N‐dimethylformamide (DMF), 1‐methylpyrrolidone (NMP), and so on. The obtained polymers showed high thermal stability with decomposition temperature around 400°C. The polyamide membranes manifest excellent mechanical properties, with Young's modulus of 2.5–5.5 GPa. Interestingly, the film of PA‐1, PA‐2, and PA‐3 is completely transparent in the visible range, while PA‐4 film is opaque. Crystallization was observed in PA‐4 film, although the molecular structure of PA‐4 is not as symmetrical as PA‐2. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Preparation and characterization of new polyamide/montmorillonite nanocomposites containing azo moiety in the main chain

Two new samples of polyamide/montmorillonite reinforced nanocomposites containing 4,4′-azobenzoic acid moiety in the main chain were synthesized by a convenient solution intercalation technique. Polyamide (PA) 4 as a source of polymer matrix was synthesized by the direct polycondensation reaction of 4,4′-azobenzoic acid 2 with 4,4′-diamino diphenyl ether 3 in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). Morphology and structure of the resulting PA-nanocomposite films 4a and 4b with 10 and 20% silicate particles were characterized by FTIR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposites films were investigated by using UV–vis spectroscopy, thermogravimetric analysis (TGA) and water uptake measurements.

Synthesis and photophysical properties of polyamides containing in-chain porphyrin and [60]fullerene

Conjugated polyamides containing porphyrin and [60]fullerene (C60) in the main chain were prepared by a direct polycondensation of the 3′H,3″H-dicyclopropa[1, 9:16, 17] [5, 6]fullerene-C60-Ih-3′,3″-dicarboxylic acid and 5,15-bis(4-aminophenyl)-10,20-bis(3,5-dialkoxyphenyl)porphyrin in the presence of triphenyl phosphite and pyridine. Gel permeation chromatography (GPC) analysis of the polyamides showed the weight-average molecular weight was about 23,626–23,736, and the temperature at 5% weight loss determined by thermogravimetric analysis (TGA) was above 216 °C. The transmission electron microscopy (TEM) images displayed the regular one-dimensional linear arrays of the polyamides with lengths exceeded 200 nm. The photoinduced electron transfer from porphyrin to C60 in the polyamides was observed in nanosecond laser-flash photolysis experiments at ambient temperature, which produced a charge-separated state (porphyrin radical cation–C60 radical anion pair) with a lifetime as long as 40 μs. The calculated ratio of kCS/kCR was found to be 2.1 × 104. They could have potential applications for photoelectronic devices, organic solar cells and so on.

Preparation and characterization of new poly(amide–imide) reinforced layer silicate nanocomposite containing N,N′-pyrromellitoyl-bis-l-phenyl acetic acid

Two new samples of poly(amide–imide)/montmorillonite reinforced nanocomposites containing N,N′-pyrromellitoyl-bis-l-phenyl acetic acid moiety in the main chain were synthesized by a convenient solution intercalation technique. Poly(amide–imide) (PAI) 3 as a source of polymer matrix was synthesized by the direct polycondensation reaction of N,N′-pyrromelitoyl-bis-l-phenyl acetic acid 1 with 4,4′-diamino diphenyl ether 2 in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). Morphology and structure of the resulting PAI-nanocomposite films 4a and 4b with 10% and 20% silicate particles were characterized by FTIR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of clay dispersion and the interaction between clay and polymeric chains on the properties of nanocomposite films were investigated by using UV–vis spectroscopy, thermogravimetric analysis (TGA) and water uptake measurements.