In this article, multi-walled carbon nanotubes (CNT's) were coated by poly(tetramethylene oxide) (PTMO) soft layer. PTMO was used for preparing segmented polyurethane (PU) films as well. PTMO-grafted CNT was utilized for loading into the PTMO-based segmented PU films in three different contents, i.e., 0.2, 0.4, and 0.8 wt.%. All PU-CNT nanocomposites were characterized by field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) techniques. The resulting nanocomposites were also investigated by thermogravimetric analysis (TG/DTG), differential thermal analysis (DTA), and dynamic mechanical thermal analysis (DMTA). DTMA results showed a significant increase in the storage moduli, especially at temperatures
AUTHOR KEYWORDS: dynamic mechanical thermal analysis; poly(tetramethylene oxide)-based polyurethane; poly(tetramethylene oxide)-functionalized carbon nanotube; polymer-matrix nanocomposites; storage modulus
INDEX KEYWORDS: Carbon films; Differential thermal analysis; Dynamic mechanical analysis; Dynamics; Elastic moduli; Enamels; Field emission microscopes; Fourier transform infrared spectroscopy; Grafting (chemical); Nanocomposites; Oxide films; Polymer matrix composites; Polyurethanes; Scanning electron microscopy; Thermogravimetric analysis; X ray diffraction; Yarn, D. dynamic mechanical thermal analyses (DMTA); Differential thermal analyses (DTA); Dynamic mechanical thermal analysis; Field emission scanning electron microscopy; Functionalized carbon nanotubes; Polymer matrix nanocomposites; Polytetramethyleneoxide; Segmented polyurethanes, Multiwalled carbon nanotubes (MWCN)
PUBLISHER: John Wiley and Sons Inc.

Karimzadeh, M., Eslampanah-Seyyedi, E., Behniafar, H. Poly(tetramethylene oxide)-coated silica nanoparticles incorporated into poly(4,4′-oxydiphenylene-pyromellitimide) matrix (2018) 33 (10), pp. 1093-1099.

DOI: 10.1080/10426914.2017.1364856

Telechelic poly(teramethylene oxide) with two isocyanate end groups (OCN-PTMO-NCO) was synthesized by the reaction of polytetrahydrofuran (Mn = 1000 g mol−1) and hexamethylene diisocyanate in 1:2 molar ratio. The resulting macrochains were then covalently grafted to the surface of silica nanoparticles (SNPs). Thus, the inorganic nanoparticles could be thoroughly coated by a thick and soft organic shell. Thermogravimetric measurements showed that up to 85 wt.% of the organically modified SNPs (OSNPs) could be formed from the organic part. Different weight ratios of OSNPs were subsequently added to a solution of 4,4′-oxydiphenylamine/pyromellitic dianhydride poly(amic acid) (PAA) in dimethylformamide. Chemical cyclodehydration of the PAA in the presence of homogeneously dispersed OSNPs resulted in poly(4,4′-oxydiphenylene-pyromellitimide) (POPI) nanocomposites, labeled by POPI/OSNP 5, POPI/OSNP 7.5, and POPI/OSNP 10. The nanocomposites obtained were fully characterized by field emission scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. According to the diffuse reflectance UV spectroscopy, in comparison with neat POPI, the POPI/OSNP series showed an appreciable redshift in the λmax values up to 15–20 nm. Moreover, POPI/OSNP series showed significant stability toward heat at temperatures above 540°C. The endothermic phase transitions occurred by the first thermodegradation of the resulting nanocomposites could be obviously seen in the differential thermal analysis. © 2017 Taylor & Francis.

In this work, diglycidyl ether of bisphenol A (DGEBA) epoxy resin was cured by isophorone diamine (IPD) hardener in the presence of amine-functionalized silica nanoparticles. Depending upon the aminated silica (AS) contents, two epoxy networks labeled by EP/AS-2.5 and EP/AS-5.0 were obtained. The amine functional groups can allow the nanoparticles to be covalently incorporated into the epoxy matrix. Two controls, including epoxy network loaded by pristine silica (EP/S-2.5) as well as neat epoxy network, were also prepared via a similar protocol. Thus, thermal and mechanical behaviors of the resulting materials were studied as a function of silica surface characteristics, i.e., hydrophilic vs. organo-modified surface, and its loading content. The initial decomposition temperatures (TIDT) and the temperatures of the maximum decomposition rate (Tmax) were improved. The AS nanoparticles could enhance the storage moduli (E′ values) of the epoxy networks at high-temperature region. Dynamic mechanical analyses also showed that the amine-functionalization of silica can lead to a superior interaction between the nanoparticles and the resulting DGEBA/IPD epoxy networks. © 2017, Springer-Verlag Berlin Heidelberg.

In this research, silica nanopowder is surface modified via a facile urethanation reaction to obtain silicon dioxide (SiO2) nanoparticles possessing amine (NH2)-functionalized organic moieties. Poly(4,4′-oxydiphenylene-pyromellitimide) as one of the most widely used polyimides (PIs) is then uniformly loaded by these organically modified nanoparticles (approximately 5% by weight) during its synthesis process at the thermal cyclodehydration stage of the corresponding poly(amic acid) precursor. Amine-functionalized SiO2 nanoparticles (SiO2∼NH2) and the resulting PI-based nanocomposites (PI/SiO2 and PI/SiO2∼NH2) are thoroughly characterized by Fourier transform infrared spectroscopy, diffuse reflectance ultraviolet-visible, X-ray diffraction, and scanning electron microscopy. Thermogravimetric analyses/derivative thermogravimetry thermograms obviously show that about 22% (by weight) of the nano-SiO2 particles is formed by organic moieties. Moreover, the thermostability order is found to be PI/SiO2 > PI/SiO2∼NH2 > neat PI. The nanocomposite PI/SiO2∼NH2 shows a two-step thermal decomposition pattern; the first step is due to the scission of the organic part from the nanoparticles loaded. According to the slope changes of the differential thermal analyses curves, the first-order phase transition could be found at the thermal range of 300-400°C. This transition, however, is not so clear for PI/SiO2 and PI/SiO2∼NH2 nanocomposites due to the interaction of nano-SiO2 particles with PI matrix. © The Author(s) 2015.

Soft and flexible chains of poly(tetramethylene glycol) (PTMG) were covalently grafted with multi-walled carbon nanotubes (MWCNT). FE-SEM images showed that the polyether PTMG formed a surrounding shell around the nanotubes with about 5 nm in thickness. The modified nanotubes (MWCNT-PTMG) were then loaded into an in situ prepared polyurethane elastomer (PUE) with different loading contents below 1 wt %. In addition to the modifier of MWCNT, polyether PTMG was also used for preparing the polyurethane matrix. Thermal analyses (TG/DTG and DTA) showed two endothermic phase transitions in associated with the two main thermo-degradations of the resulting PUE nanocomposites. Moreover, DMA technique exhibited an appreciable increase in the Tg values due to a strong interaction between PTMG-modified MWCNT and PTMG-based PUE matrix. © 2016, Pleiades Publishing, Ltd.

In this article, we report on the chemical oxidative polymerization of 3-methylthiophene (3MTh) in a concentrated TiO2/CHCl3 homogeneous suspension with an oxidant/monomer mole ratio of 3 at room temperature. According to the scanning electron microscopy images, in this condition, poly(3-methylthiophene) (P3MTh) was prepared with fibrous morphology decorated by nano-dimensional TiO2 particles. P3MTh/TiO2 was also characterized by Fourier transform infrared spectroscopy and X-ray diffraction techniques. It was found that no aggregation of nanoparticles occurred during the polymerization process. In addition, the thermal stability of P3MTh/TiO2 nanocomposite was investigated by thermogravimetric analysis and compared with that of an analogously prepared neat P3MTh. The thermal degradation of P3MTh in the temperature range of 300–550°C decreases significantly due to the presence of the TiO2 nanoparticles in the polymer composite. © 2016, Copyright © Taylor & Francis Group, LLC.

Amine-telechelic poly(tetramethylene oxide) (PTMO) was trimethylated to a quaternary ammonium (QA)-capped PTMO as a bivalent organic macrocation. This QA-capped PTMO (QAPTMO) was used for intercalation of montmorillonite (MMT) platelets with 69 % ion exchange yield and 4.03 nm d-spacing. Then, segmented polyurethanes (SPU) with PTMO soft segments were synthesized in the presence of the QAPTMO-intercalated MMT filler in different contents. According to the X-ray and SEM analyses, the polyaddition reaction could result in a full exfoliation of the clay platelets. Two model composites including SPU polymer loaded by unmodified MMT and tetradecyltrimethylammonium bromide (TTAB)-intercalated MMT were also synthesized analogously. The SPU/QAPTMO-MMT composites possessing 5.0 and 7.0 wt.% of the filler obviously showed a better thermal behavior in comparison with SPU/TTAB-MMT and SPU/Na-MMT composites. In addition, a significant increase in the storage moduli of the polyurethane matrices occurred due to the QAPTMO-MMT particles, particularly in the 5.0 wt.% loading content of the filler. © 2016, Springer Science+Business Media Dordrecht.

Ag-loaded polyaniline nanocomposites in the form of their fully oxidized pernigraniline bases (PB’s) are synthesized by one-pot chemical oxidation of aniline monomer using silver ion oxidant via two parallel methods. These two methods are compared with each other with respect to the content and size of the particle loaded. In method 1, leading to PB/Ag-1, ammonium peroxydisulfate (APS) and silver ion oxidants are used for two consecutive steps involving oxidative polymerization of aniline and oxidation of the emeraldine salt intermediate, respectively. In method 2, leading to PB/Ag-2, silver ions play the role of the oxidant in the polymerization step and inversely, APS oxidizes the intermediate salt obtained to the final nanocomposite. A significant enhancement in the content of the particle loaded could be resulted in method 2 (68.1 vs. 18.5 % by weight). Moreover, in method 2, the average size of the silver nanoparticles loaded into the PB matrix is found to be lesser than the method 1 (30 vs. 52 nm). TGA/DTG thermogram of PB/Ag-2 shows that the organic part of the nanocomposite (~30 wt%) undergoes a gradual thermo-degradation through a four-step pattern, mainly occurred at about 350 °C. © 2015, Springer Science+Business Media New York.

4,4′-Methylene diphenyl diisocyanate (MDI) played a dual role for preparing thermoplastic polyurethanes (TPU)/silica nanocomposites; both as monomer to synthesize MDI-capped poly(tetramethylene oxide) (PTMO) and as surface modifier of nano-SiO2 particles. Untreated and/or MDI-treated SiO2 were homogeneously incorporated into the resulting TPU polymer after extension of the chains by 1,4-butanediol (BDO). To modify silica nanoparticles, MDI was grafted to the surface silanol groups of the nanoparticles by forming urethane links. MDI-treated SiO2 (SiO2-MDI) nanoparticles, as well as TPU/untreated SiO2 (TPU/SiO2) and TPU/MDI-treated SiO2 (TPU/SiO2-MDI) nanocomposites were characterized by FT-IR, UV-vis DRS, XRD, SEM, mechanical, and thermal analyses. (Graph Presented). Copyright © 2015 Taylor & Francis Group, LLC.

An efficient route is used to prepare poly(3,4-ethylenedioxythiophene)/silver nanocomposite by chemical oxidative polymerization of 3,4-ethylenedioxythiophene monomer in Ag colloidal medium through emulsion technique using iron (III) p-toluenesulfonate hexahydrate (Fe(OTs)3.6H2O) oxidant. Sodium dodecyl sulfate plays a dual role involving both as emulsifier of the polymerization medium and stabilizer of the simultaneously reduced Ag nanoparticles. To compare the results obtained, an Ag-unloaded PEDOT is also prepared analogously. The resulted samples are fully characterized by fourier transform infrared, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV/vis, and thermogravimetric analyses. No remarkable aggregation of Ag nanoparticles occurs during the polymerization reaction. Moreover, average particle size of the incorporated Ag is found to be <10 nm. © 2014 Taylor & Francis.[/accordion]
AUTHOR KEYWORDS: electron microscopy; PEDOT/Ag nanocomposite; TG analysis; X-ray diffractogram
INDEX KEYWORDS: Silver colloid; TG analysis; X-ray diffractograms, Electron microscopy
PUBLISHER: Taylor and Francis Ltd.

Behniafar, H., Pouri, A.A., Yazdi, M. Aniline/Ag+ to polyaniline/Ag nanocomposite in the presence of sodium dodecyl sulfate and phenylene diamine (2015) 36 (2), pp. 253-256.

DOI: 10.1002/pc.22937

Silver ion oxidized effectively aniline monomer in the presence of p-phenylene diamine (PDA) promoter in sodium dodecyl sulfate (SDS) micellar medium to polyaniline/silver nanocomposite (PANI/Ag). To compare the results obtained, a sample of PANI polymer lacking Ag nanoparticles was also synthesized by a similar manner using ammonium peroxydisulfate instead of silver ion as the reaction oxidant. The use of PDA promoter/SDS emulsifier system could on one hand decrease the reaction time compared to those of reported previously, and on the other hand, allow the as-reduced silver particles to stay nanosized. The Ag-loaded PANI nanocomposite was structurally confirmed using Fourier transforminfrared and X-ray diffraction techniques. The uniformly-dispersed Ag nanospheres with average particle size of ∼20 nm were clearly detectable in the bright-field micrographs obtained from transmission electron microscopy. Furthermore, thermogravimetric analysis showed that major losses of the mass occurred at two temperature regions including 150-375°C and 375-800°C. © 2014 Society of Plastics Engineers.

In this work, TiO2 nanoparticles are surface modified by NH2-terminated organic moieties arised from 4,4′-methylene diphenyl diisocyanate (MDI). These nanoparticles are incorporated into ether-based segmented polyurethane (SPU) matrix. MDI is utilized as monomer together with poly(tetramethylene oxide) (PTMO) comonomer for preparing the final polymer as well. The NH2-functionalized TiO2 nanoparticles are covalently linked to the NCO terminals of the resulting SPU macromolecules during film preparation stage. Therefore, in addition to butylene glycol, these surface modified nanoparticles with enhanced organophilicity could play the role of the second chain extender of NCO-capped SPU macromolecules through formation of urea linkages. Optical and thermal behaviors of the transparent and flexible film (SPU/TiO2-MDI) is compared with those of unmodified TiO2 (SPU/TiO2) and TiO2-unloaded SPU films. Though the particle loading is only 5 wt.%, incorporation of TiO2 and TiO2-MDI nanoparticles into the SPU polymer enhances significantly the light absorption in UV region at 300-400 nm. SEM images of the prepared films clearly show a considerable decrease in particle aggregation for TiO2-MDI into SPU matrix compared to that of unmodified TiO2. TG analyses indicate a one-step decomposition pattern with onset temperatures of about 360 and 380°C for neat SPU and SPU/TiO2-MDI, respectively. Moreover, DTA thermograms of both nanocomposites show obviously two exothermic phase transitions in the thermal range of 330-440°C. © 2015 Elsevier B.V. All rights reserved.

In the present work, at first, nano-TiO2 particles in anatase form were effectively surface modified via reacting with NCO groups of 4,4′-methylenediphenyl disocyanate (MDI). Secondly, a solution of azobisisobutyronitrile (AIBN) (0.1 g) in inhibitor-free styrene (10 g) was poured into a 150 mL flask containing poly (vinyl alcohol) (PVA) suspending agent (0.1 g) in deionized water (60 mL) under N2 flow, while stirring. The reaction mixture was then heated to 80 °C, and stirred for another 1 h. Next, it was divided to two portions; one for the synthesis of pure PS, and the other for the synthesis of PS/TiO2 nanocomposites. Each aqueous portion was individually mixed with dichloromethane in a separating funnel. For PS/TiO2 nanocomposites, the organic phase was charged with nano-TiO2 particles (MDI-treated and/or untreated) (0.05 g), and then fully homogenized using ultrasonic homogenizer. Methanol non solvent was eventually used to precipitate the products. All samples involving pure PS, PS/surface modified TiO2 nanocomposite, and PS/surface unmodified TiO2 nanocomposite were thoroughly washed, filtered, and dried in vacuum at 50 °C for 12 h. From SEM images a core-shell relation could be clearly detected between the nano-TiO2 particles and PS matrix. Meanwhile, the surface modified TiO2 was dispersed into the PS matrix with better homogeneity compared to that of unmodified one. Undoubtedly, beside the surface modification factor, PVA suspending agent as an effective nanosized particle stabilizer, too, played a basic role in this high homogeneity. Also, FT-IR and XRD analyses led to promising results. © (2014) Trans Tech Publications, Switzerland.

In the present work, we have focused on the synthesis and characterization of Polystyrene (PS) nanocomposites incorporated with anatase-TiO2. The nano-TiO2 particles were used in two forms including surface modified (mod TiO2) and surface unmodified (unmod TiO2). Accordingly, two PS/TiO2 nanocomposites were synthesized, i.e. (PS/mod TiO2) and (PS/unmod TiO2), starting from styrene monomer in the presence of sodium dodecylsulfate (SDS) emulsifier. 4,4′-Methylene diphenyldiisocyanate (4,4′-MDI) was used for the surface modification of the nano-TiO2 particles via urethanation reaction with terminal -OH groups. After modification, optical behavior of the samples was determined. The chemical structure of pure polystyrene (pure-PS), (mod TiO2), (PS/mod TiO2), and (PS/unmod TiO2) was confirmed by FT-IR spectroscopy. X-ray diffraction (XRD) analyses obviously showed the broad peak related to the (pure-PS) centered at 2θ of 20 ° as well as the sharp characteristic peak of the TiO2 nanoparticles appeared at about 2θ of 25 °. Moreover, diffuse reflectance UV/vis spectroscopy analyses, (mod TiO2) and (PS/mod TiO2) samples showed strong visible absorption at the range of 400 to 600 nm. © (2014) Trans Tech Publications, Switzerland.

This study describes a facile method for preparing poly(4,4′- oxydiphenylene-pyromellitimide) (POPI)/TiO2 nanocomposites. 4,4′-Methylene diphenyl diisocyanate (MDI) was used as the surface modifier of TiO2 nanoparticles. MDI-modified and/or unmodified TiO2 were added to a viscose solution of poly(amic acid) (PAA) prepared by reacting 4,4′-oxydiphenylamine and pyromellitic dianhydride (PMDA). Casting the homogenized mixture onto glass Petri dishes gave the corresponding thermally cured films of POPI/TiO2 and POPI/TiO 2-MDI nanocomposites through cyclodehydration of the PAA precursor. Diffuse reflectance UV/vis spectroscopy (UV/vis DRS) indicated that two absorption maxima are developed in the spectrum of MDI-treated TiO2 at about 440 and 580 nm, as well as a slight red shift in the absorption maxima of POPI/TiO2 and POPI/TiO2-MDI nanocomposites compared to the neat POPI occurred. From XRD measurements the mean sizes of nano-TiO 2 in TiO2-MDI, POPI/TiO2, and POPI/TiO 2-MDI were found to be 27, 22, and 19 nm, respectively. According to the SEM images of POPI/TiO2 and POPI/TiO2-MDI nanocomposites, the nano-sized TiO2 particles with globular shapes were dispersed into the polymer matrix. According to the TGA/DTG thermograms it could be deduced that the incorporation of nano-TiO2 particles into the polymer matrix can lead to an appreciable thermostability. Taking into account, the DTA thermograms a discrete endothermic transition could be detected at about 290 °C. MDI-grafted TiO2 seems to be a good candidate for incorporating into poly(4,4′-oxydiphenylene-pyromellitimide) as a commercial type polyimide. © 2014 Springer-Verlag Berlin Heidelberg.

Polypyrrole/palladium (PPy/Pd) nanocomposites, labeled by PPy/Pd-2/1-0, PPy/Pd-2/1-25, and PPy/Pd-3/1-0, are synthesized via a direct redox reaction between pyrrole monomer and PdCl2 in the presence of sodium dodecyl sulfate (SDS) stabilizer in chloroform (CHCl3)/acetonitrile (CH 3CN) binary organic solvents with 2:1 and 3:1 volume ratios at two temperatures involving 0 and 25 °C. A Pd-unloaded polypyrrole (PPy-2/1-0) is also synthesized similarly using iron(III) chloride (FeCl3) oxidant for comparison purposes. The volume ratio of the solvents used as well as the temperature at which the oxidative polymerization takes place affects significantly the thermostability of the resulting nanocomposites. According to the thermogravimetric analyses, the stability order towards heat is found to be PPy/Pd-2/1-25>PPy/Pd-2/1-0>PPy/Pd-3/1-0>PPy-2/1-0. The nanocomposite PPy/Pd-2/1-25 shows clearly more thermostability compared to PPy/Pd-2/1-0 analog at temperatures above 400 °C. Furthermore, whereas three discrete maxima can be obviously found in the differential thermal analysis (DTA) thermogram of PPy-2/1-0 pure sample, no distinctive exothermic peak is observed in the curves of the three Pd-loaded nanocomposites. © 2014 Springer-Verlag.

In this study, we prepared poly(3,4-ethylenedioxythiophene) (PEDOT) via the chemical oxidation of the 3,4-ethylenedioxythiophene monomer in a system consisting of miscible binary organic solvents, that is, acetonitrile (CH 3CN) and chloroform (CHCl3). This successful technique was then used to synthesize a poly(3,4-ethylenedioxythiophene) (PEDOT)/silver (Ag) nanocomposite as well. In this facile and efficient technique, a higher solubility of the oxidizing reagent, which originated from a relative enhancement in the polarity of the reaction medium, led to significant changes in the optical and thermal behaviors of the resulting products. To investigate the degree of validity of the technique applied, a pure sample of PEDOT (PEDOT I) was also synthesized with CHCl3 alone, and this was then compared with a sample prepared in CH3CN/CHCl3 binary solvents (PEDOT II). To prepare the PEDOT/Ag nanocomposite, first the PEDOT synthesized in binary solvents was thoroughly dissolved in a dimethyl sulfoxide solvent. Next, Ag nanopowder was uniformly dispersed in the previous solution of PEDOT with sonication. The PEDOT/Ag nanocomposite was then precipitated through the addition of a methanol nonsolvent. The approximate size of nano-Ag within the polymer matrix was found to be about 40 nm. Scanning electron microscopy images of the pure PEDOT II and PEDOT/Ag nanocomposite exhibited an agglomerated sponge and nanospherical homogeneity, respectively. In comparison with PEDOT I, considerable redshifts in the ultraviolet-visible absorption spectra of the pure PEDOT II and PEDOT/Ag nanocomposite were observed. In addition, the thermostability order was found to be PEDOT/Ag > PEDOT II > PEDOT I at all temperatures above 300°C. © 2013 Wiley Periodicals, Inc.

In this research, a new facile and efficient route has been employed to prepare poly(3,4-ethylenedioxythiophene)/titanium dioxide (PEDOT/TiO 2) nanocomposites using chloroform-acetonitrile binary solvents. Two homogenized and stabilized chloroform-based nanofluids were separately prepared with titanium dioxide nanoparticles in the presence of two anionic and cationic surfactants, i.e. sodium dodecylbenzene sulfonate (SDBS) and tetradecyltrime-thylammonium bromide (TTAB) by sonication. Next, 3,4-ethylenedioxythiophene (EDOT) monomer was added to these nanofluids. A solution of iron (III) chloride oxidant in acetonitrile was then slowly poured into the previous mixture. The chemical oxidative polymerizations resulted in the preparation of PEDOT/TiO2 in a medium of the two mentioned miscible organic solvents. To compare the results obtained, pure PEDOT as a reference was also prepared by a similar manner to that of used to prepare PEDOT/TiO2 nanocomposites. UV-vis diffuse reflectance spectra (DRS) were utilized to investigate the effect of the incorporated nano-TiO2 particles on optical properties of PEDOT. X-ray diffraction (XRD) patterns obviously showed the characteristic peaks of embedded TiO2 nanoparticles on the diffractogram of the resulting PEDOT. Surface morphology of the nanocomposites was evaluated by scanning electron microscopy (SEM) analyses. Transmission electron microscopy (TEM) images demonstrated that the TiO2 nanoparticles were uniformly dispersed in both PEDOT bulks. Thermogravimetric analysis (TGA/DTG) clearly showed that both PEDOT/TiO 2 nanocomposites are more stable toward heat compared with the pure PEDOT sample. © 2013 Springer Science+Business Media Dordrecht.

In this research, a new fluorinated diamine based on 2,2′-substituted 1,1′-binaphthyl units, 2,2′-bis(2-amino-4-trifluoromethylphenoxy)-1,1′-binaphthyl (AFPBN) was synthesized and then used to prepare the corresponding ortho-linked poly(ether-imide)s via chemical polyimidization with several aromatic carboxylic dianhydrides. The resulting poly(ether-imide)s were fully characterized by FT-IR, NMR, viscosity measurements, gel-permeation chromatography, UV-vis, X-ray diffraction, organo-solubility, thermogravimetric analysis (TGA), and differential scanning calorimetry. Probing optical behavior of the colorless films prepared from these poly(ether-imide)s demonstrated that they possess a high degree of optical transparency, and UV-visible absorption cut-off wavelength values were found to be in the range of 404-471nm. The resulting polymers exhibited excellent organo-solubility in polar solvents such as dimethylformamide, dimethyl sulfoxide, pyridine, and even tetrahydrofuran. To investigate the heat stability of the samples, their thermograms obtained from TGA were plotted, and for example, it is found that the 10% weight loss temperature of representative polymer AFPBN/3,3′,4,4′-benzophenonetetracarboxylic dianhydride occurred at 532°C in nitrogen. These poly(ether-imide)s had glass-transition temperatures (Tg's) up to 280°C. Two previously prepared analogues of AFPBN, i.e. nonfluorinated diamine DAM1 and para-linked fluorinated diamine DAM2 used to prepare the corresponding poly(ether-imide)s, were also considered to compare the results obtained. © 2012 John Wiley & Sons, Ltd.

A new dicarboxylic acid monomer, 2,6-bis(1,3-dioxo-5-carboxyisoindolin-2- yl)-4,4'-bis(trifluoromethyl)-1,1'-diphenyl ether (IFDPE), bearing two preformed imide rings was synthesized via a three-step manner from 4-(trifluoromethyl) phenol and 4-chloro-3,5-dinitrobenzotrifluoride. The monomer IFDPE was then used to prepare a series of novel trifluoromethyl-containing poly(amide-imide)s via a direct phosphorylation polycondensation with various aromatic diamines. The intrinsic viscosities of the polymers were found to be in the range 0.86-1.02 d/g. The weight- and number-average molecular weights of the resulting polymers were determined with gel permeation chromatography. The polymeric samples were readily soluble in a variety of organic solvents and formed low-color, flexible thin films via solution casting. The values of the absorption edge wavelength were determined by ultraviolet-visible spectroscopy, and all of the resulting poly (amide-imide)s films exhibited high optical transparency. The resulting polymers showed moderately high glass-transition temperatures in the range 295-324°C and had 10% weight loss temperatures in excess of 524°C in nitrogen. The crystallinity extents were qualitatively investigated with wide-angle X-ray diffraction measurements. Scanning electron microscopy images revealed an agglomerated bulk with nonuniformity on the surface. Copyright © 2012 Wiley Periodicals, Inc.

A structurally kinked fluorinated diacid, 2,6-bis(N-trimellitimido)-4- trifluoromethyl-4′-phenoxydiphenyl ether (TFPDPE) was synthesized and then used for preparing a new class of fluoro-containing poly(amide-imide)s via phosphorylation polyamidation with four diamines including 4,4′- (oxidianiline, 2,6-diamino-4-trifluoromethyl)-4′-phenoxydiphenyl ether, 1,5-bis(2-amino4-trifluoromethylphenoxy)naphthalene, and 2,2′-bis(2-amino- 4-trifluoromethylphenoxy)-1,1′-binaphthyl. Chemical structure of monomer TFPDPE as well as the resulted polymers was fully confirmed by IR and NMR spectroscopy. Limited viscosity numbers ([η]'s) of the resulting polymers at 25°C were measured. The values of M̄w and M̄n were determined using gel-permeation chromatography (GPC). In addition, the absorption edge values (λ 0) obtained from their UV curves were determined, and all the resulting poly(amide-imide)s exhibited high optical transparency. The crystallinity of the polymers was estimated by wide-angle X-ray diffraction (WXRD), and the resulted polymers exhibited nearly an amorphous nature. To study on the surface morphologies, the scanning electron microscopy (SEM) images of the poly(amide-imide)s were taken. Furthermore, solubility of the samples in various kinds of organic solvents was tested. From differential scanning calorimetric (DSC) analyses, the polymers showed T g's between 304 and 328°C. Thermo-stability of the polymers was determined by thermogravimetric analysis (TGA), and the 10% weight loss temperatures of the poly(amide-imide)s were found to be in the range of 548-553°C. © 2012 Elsevier B.V. All rights reserved.

A new ortho-linked dicarboxylic acid monomer, 1,5-bis(4-trifluoromethyl-2- trimellitimidophenoxy)naphthalene (BFTPN), bearing two preformed imide rings, two trifluoromethyl groups, and two ether linkages was synthesized by the condensation reaction between 1,5-bis(2-amino-4-trifluoromethylphenoxy) naphthalene (BAFPN) and trimellitic anhydride in refluxing glacial acetic acid. Monomer BFTPN was then utilized to prepare a series of novel trifluoromethyl-containing poly(amide-imide)s via a direct phosphorylation polycondensation with various aromatic diamines. Weight and number-average molecular weights (M̄ w and M̄ n) of the resulting polymers were determined using gel-permeation chromatography (GPC). The polymeric samples were readily soluble in a variety of organic solvents and formed low-colored and flexible thin films via solution casting. The values of absorption edge wavelength (λ 0) were determined by UV-vis spectroscopy, and all of the resulting poly(amide-imide)s films exhibited high optical transparency. From differential scanning calorimetry (DSC) thermograms, the polymers showed glass-transition temperatures between 305 and 323°C. Thermal behaviors of the obtained polymers were characterized by thermogravimetric analysis (TGA), and the 10% weight loss temperatures of the poly(ester-ether-imide)s were found to be in excess of 520°C in nitrogen. © 2011 Elsevier Ltd. All rights reserved.

A new diamine, 2,2′-bis(3,4,5-trifluorophenyl)-4,4′-diaminodiphenyl ether (FPAPE) was synthesized through the Suzuki coupling reaction of 2,2′-diiodo-4,4′-dinitrodiphenyl ether with 3,4,5-trifluorophenylboronic acid to produce 2,2′-bis(3,4,5-trifluorophenyl)-4,4′-dinitrodiphenyl ether (FPNPE), followed by palladium-catalyzed hydrazine reduction of FPNPE. FPAPE was then utilized to prepare a novel class of highly fluorinated all-aromatic poly(ether-imide)s. The chemical structure of the resulting polymers is well confirmed by infrared and nuclear magnetic resonance spectroscopic methods. Limiting viscosity numbers of the polymer solutions at 25 °C were measured through the extrapolation of the concentrations used to zero. M n and M w of these polymers were about 10 000 and 25 000 g mol -1, respectively. The polymers showed a good film-forming ability, and some characteristics of their thin films including color and flexibility were investigated qualitatively. An excellent solubility in polar organic solvents was observed. X-ray diffraction measurements showed that the fluoro-containing polymers have a nearly amorphous nature. The resulting polymers had T g values higher than 340 °C and were thermally stable, with 10% weight loss temperatures being recorded above 550 °C. Based on the results obtained, FPAPE can be considered as a promising design to prepare the related high performance polymeric materials. © 2011 Society of Chemical Industry.

A new diamine, 1,5-bis(2-amino-4-trifluoromethylphenoxy)naphthalene (DA1524) was synthesized by the nucleophilic substitution reaction of 1,5-dihydroxynaphthalene and 4-chloro-3-nitrobenzotrifluoride in the presence of potassium carbonate in N,N-dimethylformamide, followed by catalytic reduction with hydrazine and Pd/C in ethanol. DA1524 was then utilized to prepare a novel class of CF3-containing polyimides. Intrinsic viscosities [η] of the polymer solutions at 25 °C were measured by the extrapolation of their viscosity numbers till zero concentration. M̄w and M̄n values of the resulting polymers were determined using gel-permeation chromatography (GPC). The polymers showed a good film-forming ability, and some characteristics of their thin films including color and flexibility were investigated qualitatively. In addition, the absorption edge values (λ0) obtained from their UV-vis curves were determined, and all the resulting polyimides films exhibited high optical transparency. Thermal stability of the polymers was investigated using TGA analyses. The Tg values of the polyimides obtained from their DSC plots were quantified. Solubility of the samples in a variety of organic solvents was also tested. © 2011 Published by Elsevier B.V. All rights reserved.

An imide ring-containing diacid, 2,2′-diphenyl-4,4′-bis(N- trimellitoyl)diphenyl ether (PTPE) was synthesized through a three-step pathway starting from 2,2′-diiodo-4,4′-dinitrodiphenyl ether. A series of novel aromatic poly(amide-imide)s having bulky phenyl pendant groups at 2,2′-disubstituted positions were then prepared via a direct phosphorylation polycondensation between PTPE and various aromatic diamines. Chemical structure of the new monomer as well as the resulted polymers was thoroughly confirmed by IR and NMR spectroscopic methods. Intrinsic viscosities [η] of the polymer solutions at 25 °C were measured by the extrapolation of their viscosity numbers till zero concentration. Mw and Mn values of the resulting polymers were determined using gel-permeation chromatography (GPC). The polymers showed a good film-forming ability, and some characteristics of their thin films including color and flexibility were investigated qualitatively. In addition, the absorption edge values (λ0) obtained from their UV curves were determined, and all the resulting poly(amide-imide)s films exhibited high optical transparency. Thermal stability of the polymers using their TGA thermograms was investigated. The Tg values of the poly(amide-imide)s obtained from their DSC plots were also quantified. Crystallinity amount of the prepared macromolecules was evaluated using wide-angle X-ray diffraction (XRD). Furthermore, solubility of the samples in a variety of organic solvents including dimethyl sulfoxide (DMSO), N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), N-methyl-2-pyrrolidone (NMP), pyridine, tetrahydrofuran (THF), and toluene was tested. © 2011 Elsevier Ltd. All rights reserved.

A new class of highly fluorinated aromatic poly(ether-amide)s was prepared through triphenyl phosphite-activated polycondensation of 2,2′-bis(3,4,5- trifluorophenyl)-4,4′-diaminodiphenyl ether (FPAPE) and four dicarboxylic acid comonomers. All the resulting polymers were thoroughly characterized by FT-IR, UV, and NMR spectroscopic methods. The effects of the fluorine atoms directly linked to the lateral phenyl rings as well as fluoro-containing phenyl groups attached to the macromolecular chains on some properties of the polymers were investigated by comparing with poly(ether-amide)s prepared from 4,4′-oxydianiline (4,4′-ODA) and 2,2′-diphenyl-4,4′- diaminodiphenyl ether (PAPE). The FPAPE-derived polymers exhibited excellent solubility in a variety of organic solvents. Results obtained from X-ray studies showed that the presence of the bulky fluoro-containing phenyl groups attached to the chains disrupts their structural order in a great amount, and leads to a decrease in crystallinity extent of the macromolecules. Furthermore, the highly fluorinated polymeric chains showed a significant enhancement in organo-solubility, heat-stability and Tg values when compared to their non-fluorinated counterparts. © 2011 Elsevier B.V. All rights reserved.

A new class of alternate aromatic poly (ether-urea)s having bulky phenoxy phenyl lateral groups was prepared by the reaction of 2,2′-bis[(p-phenoxy phenyl)]-4,4′-diaminodiphenyl ether (PPAPE) with two diisocyanates, isophorone diisocyanate and 2,4-tolylene diisocyanate. The limited viscosity values as well as M̄n and M̄w values of the resulting polymers were determined. The resulting poly(ether-urea)s could be easily cast into optically-transparent, flexible, and light color films. The cut-off wavelength values and the percentage of transmittance at 800 nm were found to be at about 415 nm and 85%, respectively. PPAPE-derived poly(ether-urea)s showed a low-crystallinity and had excellent solubility in polar organic solvents. Tonset, Tg, Td5%, and Td10% values of the PPAPE-derived polymers measured from their DSC and TGA thermograms were up to 270, 280, 315, and 340°C, respectively. Surface morphology of the resulted poly(ether-urea)s were also evaluated by their scanning electron microscopy images. Excellent organosolubility, satisfactory film quality, moderate Tg values, and good thermal stability make this class of poly (ether-urea)s promising high-performance polymeric materials. © 2010 Wiley Periodicals, Inc.

In this research a diamine monomer containing two phenoxy phenylene lateral groups, 2,2'-bis[(p-phenoxy phenyl)]-4,4'-diaminodiphenyl ether (PPAPE) was used to prepare novel wholly aromatic polyimides by thermal or chemical two-step polycondensation reactions. Comonomers including pyromellitic dianhydride (PMDA), 4,4'-oxydiphthalic anhydride (ODPA), and 3,3',4,4'- benzophenonetetracarboxylic dianhydride (BTDA) were used for the polyimidization reactions. A reference polyimide was also prepared by the reaction of 4,4'-diaminodiphenyl ether (DADPE) with pyromellitic dianhydride (PMDA). The limited viscosity numbers as well as ̄n and ̄w values of the resulting polymers were determined. All PPAPE-resulted polyimides had excellent organosolubility in common polar solvents. A low crystallinity extent was only observed using their wide-angle X-ray diffractograms (WAXD). The prepared hinged polyimides could also be cast into transparent and flexible films. The glass transition temperatures of the resulting polyimides were determined by differential scanning calorimetry (DSC) analyses. The thermograms obtained from thermogravimetric analyses (TGA) showed that the phenoxy phenylene lateral groups attached to the macromolecular backbones had no substantial diminishing effect on the thermal stability of these structurally-modified polyimides.

A series of novel aromatic poly(ester-etherimide) s with inherent viscosity values of 0.44-0.74 dL g-1 were prepared by the diphenylchlorophosphate-activated direct polycondensation of an imide ring-containing diacid namely 5-(4-trimellitimidophenoxy)-1-trimellitimido naphthalene (1) with various aromatic dihydroxy compounds in the presence of pyridine and lithium chloride. Owing to comparison of the characterization data, an ester-containing model compound (2) was also synthesized by the reaction of 1 with phenol. The model compound 2 and the resulted polymers were fully characterized by FT-IR and NMR spectroscopy. The ultraviolet λmax values of the poly(ester-ether-imide)s were also determined. The resulting polymers exhibited an excellent organosolubility in a variety of high polar solvents such as N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, and N-methyl-2-pyrrolidone. They were soluble even in common less polar organic solvents such as pyridine, m-cresol, and tetrahydrofuran on heating. Crystallinity of the polymers was estimated by means of wide-angle X-ray diffraction. The resulted polymers exhibited nearly an amorphous nature. From differential scanning calorimetry thermograms, the polymers showed glass-transition temperatures between 221 and 245°C. Thermal behaviors of the obtained polymers were characterized by thermogravimetric analysis, and the 10% weight loss temperatures of the poly(ester-ether-imide)s were found to be over 410°C in nitrogen. © 2009 Wiley Periodicals, Inc.

In this research a new structurally-modified monomer, 2,2′-bis[(p- phenoxy phenyl)]-4,4′-diaminodiphenyl ether (PPAPE) was synthesized by a three-step manner starting from 4,4′-dinitrodiphenyl ether. Novel classes of wholly aromatic polyamides and polyimides were prepared from PPAPE through the conventional polycondensation reactions including triphenyl phosphateactivated phosphorylation method for the preparation of the polyamides and cyclodehydration of in situ-formed polyamic acid precursors for the preparation of the polyimides. M̄ n and M̄ w values were determined by GPC measurements. Crystallinity, organosolubility, and qualitative film characteristics of the resulting aromatic polyamides and polyimides were investigated. A low crystallinity extent was only observed using their wide-angle X-ray diffractograms. All polymers had excellent organosolubility in common polar solvents such as DMAc, DMF, DMSO, and NMP. The resulting well-designed polymers could also be cast into transparent and flexible films. © (2010) Trans Tech Publications.

Background: Wholly aromatic polyamides (aramids) are high-performance polymeric materials with outstanding heat resistance and excellent chemical stabilities due to chain stiffness and intermolecular hydrogen bonding of amide groups. Synthesis of structurally well-designed monomers is an effective strategy to prepare modified forms of these aramids to overcome lack of organo-solubility and processability limitations. Results: A novel class of wholly aromatic polyamides was prepared from a new diamine, namely 2,2′-bis (p-phenoxyphenyl)-4,4′-diaminodiphenyl ether (PPAPE), and two simple aromatic dicarboxylic acids. Two reference polyamides were also prepared by reacting 4,4′-diaminodiphenyl ether with the same comonomers under similar conditions.-Mw and -Mn of the resultant polymers were 8.0 × 104 and 5.5 × 104 gmol-1, respectively. Polymers resulting from PPAPE exhibited a nearly amorphous nature. These polyamides exhibited excellent organo-solubility in a variety of polar solvents and possessed glass transition temperatures up to 200 C. The 10% weight loss temperatures of these polymers were found to be up to 500 °C under anitrogen atmosphere. The polymers obtained from PPAPE could be cast into transparent and flexible films from N, N-dimethylacetamide solution. Conclusion: The results obtained show that the new PPAPE diamine can be considered as a good monomer to enhance the processability of its resultant aromatic polyamides while maintaining their high thermal stability. The observed characteristics of the polyamides obtained make them promising high-performance polymeric materials. © 2009 Society of Chemical Industry.

In this research a new diimide-diacid monomer, 2,2′-bis(4-phenoxyphenyl)-4,4′-bis(N-trimellitoyl)diphenyl ether (BPDPE) containing two laterally-attached phenoxy phenylene groups was prepared by the reaction of 2,2′-bis[(p-phenoxy phenyl)]-4,4′-diaminodiphenyl ether (PPAPE) with trimellitic anhydride in refluxing glacial acetic acid. Ether-hinged wholly aromatic poly(amide-imide)s with limited viscosity number values of 0.61-0.87 dL g-1 were prepared by triphenyl phosphate (TPP)-activated polycondensation of BPDPE with diamines including PPAPE and 4,4′-diaminodiphenyl ether (DADPE). For comparative purposes, reference poly(amide-imide)s were also prepared by reacting diimide-diacid monomer lacking phenoxy phenylene lateral groups namely 4,4′-bis(N-trimellitoyl)diphenyl ether (BTDPE) with the same diamines under similar conditions. A model compound MODEL was also synthesized by the reaction of BTBPE with two mole equivalents of aniline to compare the spectral characteristics results. Number and weight average molecular weights (over(M, -)n and over(M, -)w) were determined by gel permeation chromatography (GPC) technique. The phenoxy phenylene-containing poly(amide-imide)s (all, except that of resulted from BTDPE and DADPE) had excellent organosolubility in common polar solvents. A low crystallinity extent was only observed using their wide-angle X-ray diffractograms (WAXD). A qualitative study showed the prepared polymers could also be cast into optically-transparent and flexible thin films. The ether-containing lateral groups attached to the ether-hinged macromolecular main chains had no substantial diminishing effect on the thermal stability of these structurally-modified poly(amide-imide)s. © 2009 Elsevier Ltd. All rights reserved.

The relationship between thermal decomposition temperature and structure of a new data set of eighty monomers of different polymers were studied by multiple linear regression (MLR). The stepwise method was used in order to variable selection. The best descriptors were selected from over 1400 descriptors including; topological, geometrical, electronic and hybrid descriptors. The effect of number of descriptors on the correlation coefficient (R) and F-ratio were considered. Two models were suggested, one model having four descriptors (R2 = 0.894, Q2 cv = 0.900, F = 172.1) and other model involving 13 descriptors (R2 = 0.956, Q 2 cv = 0.956, F = 125.4).

A new family of wholly aromatic poly(urea-ether-imide)s (4a-4f) possessing binaphthylene-twisted rings was prepared by diphenyl azidophosphate (DPAP)-activated one-pot polyaddition reaction of a preformed imide heterocyclic ring-containing dicarboxylic acid, 2,2′-bis(4-trimellitimidophenoxy)-1,1′-binaphthyl (1) with various kinds of aromatic diamines (3a-3f). At first, with due attention to structural similarity and to compare the characterization data, a model compound 2 was synthesized by the reaction of diimide-dicarboxylic acid 1 with two mole equivalents of aniline. In this direct method, the polymers were prepared by polyaddition reactions of the in situ-formed diisocyanate with the aromatic diamines. Molecular weights of the poly(urea-ether-imide)s obtained were evaluated viscometrically, and the inherent viscosities (ηinh) measured were in the range 0.10-0.25 dl/g. All of the polymers were characterized by FT-IR spectroscopic method and elemental analysis. All of the resulting polymers exhibited an excellent solubility in common polar solvents such as N-methyl-2-pyrrolidone (NMP), dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), and N,N-dimethylacetamide (DMAc). Crystallinity of the resulted polymers was evaluated by wide-angle X-ray diffraction (WXRD) method, and they exhibited nearly a non-crystalline nature as evidenced by their diffractograms. The glass transition temperatures (Tg) of the polymers determined by differential scanning calorimetry (DSC) thermograms were in the range of 274-302°C. The temperatures at 10% weight loss (Td10%) from their thermogravimetric analysis (TGA/DTG) curves were found to be in the range of 389-414°C in nitrogen atmosphere. Copyright © 2008 John Wiley & Sons, Ltd.

A new class of aromatic poly(urea-imide)s having biphenylene pendant group was prepared by the diphenyl azidophosphate (DPAP) activated one-pot polyaddition reaction of a preformed imide ring-containing dicarboxylic acid, 4-p-biphenyl-2,6-bis(4-trimellitimidophenyl)pyridine (1) with various aromatic diamines. A model compound was also synthesized by the reaction of diimide-dicarboxylic acid 1 with two mole equivalents of aniline. In this direct method the polymers were prepared by polyaddition reactions of the in situ-formed diisocyanate with the aromatic diamines. The inherent viscosities of the polymers were measured in the range of 0.11-0.15 dL g-1. The ultraviolet λmax values of the poly(urea-imide)s were also determined. Furthermore, crystallinity of the resultant polymers was evaluated by wide-angle X-ray diffraction method, and they exhibited nearly a noncrystalline nature. All of the resulting polymers exhibited excellent solubility in common polar solvents. The glass transition temperatures of the polymers determined by DSC thermograms were in the range 241-272°C. The temperatures at 10% weight loss from their TGA curves were found to be in the range 406-437°C in nitrogen. © 2008 Wiley Periodicals, Inc.

New aromatic diimide-dicarboxylic acid having flexible ether linkage, 5-(4-trimellitimidophenoxy)-1-trimellitimido naphthalene, was synthesized by the reaction of trimellitic anhydride with 5-(4-aminophenoxy)-1-naphthylamine. Then, a series of novel aromatic poly(amide-ether-imide)s were prepared by the phosphorylation polycondensation of the synthesized monomer with various aromatic diamines. A model compound was synthesized by the reaction of the monomer with aniline. The resulting polymers with inherent viscosities of 0.43-0.70 dl/g were obtained in high yield. All new compounds including the naphthalene-based monomer, model compound, and the resulted polymers were characterized by FT-IR and NMR spectroscopic methods. The ultraviolet λmax values of the poly(amide-ether-imide)s were also determined. The resulted polymers exhibited a good solubility in a variety of high polar solvents such as N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N-methyl-2-pyrrolidone (NMP), and pyridine. For some of the polymers obtained the crystallinity behavior was estimated by means of wide-angle X-ray diffraction (WXRD) method, and the resulted polymers exhibited nearly an amorphous nature. Thermal stability of the obtained polymers was determined by thermogravimetric analysis (TGA/DTG), and the 10% weight loss temperatures of the one-step degraded poly(amide-ether-imide)s were found to be in the range between 528 and 551 °C in nitrogen. From differential scanning calorimetric (DSC) analyses, the polymers showed Tgs between 276 and 307 °C. Cyclic voltammetry (CV) measurements of a typical polymer showed that they are also electrochemically stable. © 2008 Elsevier Ltd. All rights reserved.

A novel class of wholly aromatic poly(ester-imide)s, having a biphenylene pendant group, with inherent viscosities of 0.32-0.49 dLg-1 was prepared by the diphenylchlorophosphate-activated direct polyesterification of the preformed imide-ring-containing diacid, 4-p-biphenyl-2,6-bis(4-trimellitimidophenyl)pyridine (1) with various aromatic dihydroxy compounds in the presence of pyridine and lithium chloride. A reference diacid, 2,6-bis(trimellitimido)pyridine (2) without a biphenylene pendant group and two phenylene rings in the backbone, was also synthesized for comparison purposes. At first, with due attention to structural similarity and to compare the characterization data, a model compound (3) was synthesized by the reaction of compound 1 with two mole equivalents of phenol. Moreover, the optimum condition of polymerization reactions was obtained via a study of the model compound synthesis. All of the resulting polymers were characterized by Fourier transform infrared and 1H NMR spectroscopy and elemental analysis. The ultraviolet λ max values of the poly(ester-imide)s were also determined. All of the resulting polymers exhibited excellent solubility in common organic solvents, such as pyridine, chloroform, tetrahydrofuran, and m-cresol, as well as in polar organic solvents, such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, and dimethyl sulfoxide. The crystalline nature of the polymers obtained was evaluated by means of wide-angle X-ray diffraction. The resulting poly(ester-imide)s showed nearly an amorphous nature, except poly(ester-imide) derived from 4,4′-dihydroxy biphenyl. The glass transition temperatures (Tg) of the polymers determined by differential scanning calorimetry thermograms were in the range 298-342 °C. The 10% weight loss temperatures (T10%) from thermogravimetric analysis curves were found to be in the range 433-471 °C in nitrogen. Films of the polymers were also prepared by casting the solutions. © 2006 Society of Chemical Industry.

An imide ring-containing diamide-dianhydride, N-[3,5-bis(3,4-dicarboxybenzamido)phenyl]phthalimide dianhydride (1) was prepared by the reaction of trimellitic anhydride chloride with N-(3,5-diaminophenyl)phthalimide in a medium consisting of methylene chloride and pyridine. A series of new alternating aromatic poly(amide-imide)s having inherent viscosities of 0.26-0.37 dl/g was synthesized using a two-step poly(amic-acid) precursor method. A reference monomer, 1,3-bis(3,4-dicarboxybenzamido)benzene dianhydride (2) without the phthalimido pendant group attached to the polymer main chain was prepared in order to study the structure-property relationship. In this case, the structure effects on some properties of the resulting poly(amide-imide)s including crystallinity, solubility, thermal stability, and film flexibility could be easily clarified. A diamide-triimide (3) as a model compound was also synthesized by the reaction of new dianhydride 1 with aniline to compare the characterization data as well as to optimize the polymerization conditions. The resulting polymers were fully characterized by FT-IR, UV-visible and 1H NMR spectroscopy. Most of the polymers showed an amorphous nature and were readily soluble in a variety of organic solvents such as N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N-methyl-2-pyrrolidone (NMP), and pyridine. The glass-transition temperatures of these polymers were recorded between 301 and 371 °C. All polymers showed no significant weight loss below 500 °C in nitrogen, and the decomposition temperatures at 10 wt.% loss range from 506 to 543 °C. The films of the resulting poly(amide-imide)s could be cast from their NMP solutions, and the transparency and flexibility of them were investigated. © 2006 Elsevier Ltd. All rights reserved.

The direct preparation of various aromatic poly(urethane-imide)s from 4-p-biphenyl-2,6-bis(4-trimelliti-midophenyl)pyridine (1) using diphenylphosphoryl azide (DPPA) was investigated. The polymers were mainly obtained by the conversion of imide ring-containing diacid 1 to corresponding di(carbonyl azide) 2 with DPPA and then to diisocyanate 3 through the Curtius rearrangement of compound 2 followed by polyaddition of 3 in different amounts with aromatic dihydroxy compounds. The molecular weights of the resulting poly(urethane-imide)s were evaluated viscometrically. All of the resulted polymers were thoroughly characterized by spectroscopic methods and elemental analyses. The poly(urethane-imide)s exhibited an excellent solubility in a variety of polar solvents. Crystallinity nature of the polymers was estimated by means of WXRD. The glass-transition temperatures of the polymers determined by DSC method were in the range of 191-202°C. The 10% weight loss temperatures of the poly(urethane-imide)s from their thermal gravimetric analysis curves were found to be in the range of 392-416°C in nitrogen. The films of the resulting polymers were also prepared by casting the solution. © 2006 Wiley Periodicals, Inc.

The direct preparation of various aromatic poly(urea-imide)s (5a 1- 5b4) from N-[3,5-bis(trimellitimido)phenyl]phthalimide (1) using diphenylphosphoryl azide (DPPA) was investigated. The polymers were obtained by the conversion of imide ring-containing diacid 1 to corresponding di(carbonyl azide) 2 with DPPA and then to diisocyanate 3 through the Curtius rearrangement of compound 2. This was followed by poly-addition of 3 with two aromatic diamines (4a and 4b). In order to compensate the diisocyanate shortage against the diamines, some excess amounts of the initial triimide-dicarboxylic acid 1 were used. The molecular weights of the resulting poly(urea-imide)s were evaluated viscometrically. The poly(urea-imide)s exhibited an excellent solubility in a variety of polar solvents. The crystallinity nature of the polymers was estimated by means of WXRD. The glass transition temperatures and the 10% wt loss temperatures of the polymers 5a3 and 5b3 were determined by DSC and TGA/DTG methods in nitrogen atmosphere, respectively. The transparent films of the resulting polymers were also prepared by casting the solution.

A new imide-containing dicarboxylic acid based on a twisted binaphthylene unit, 2,2′-bis(N-trimellitoyl)-1,1′-binaphthyl (1), was synthesized from 1,1′-binaphthyl-2,2′-diamine and trimellitic anhydride in glacial acetic acid. The structure of compound 1 was fully characterized with spectroscopic methods and elemental analysis. Series of thermally stable and organosoluble poly(amide imide)s (4a-4d) and poly(ester imide)s (5a-5d) with similar back-bones were prepared by the triphenyl phosphite and diphenylchlorophosphate activated direct polycondensation of diimide dicarboxylic acid 1 with various aromatic diamines and diols, respectively. With due attention to the structural similarity of the resulting poly(amide imide)s and poly(ester imide)s, most of the differences between these two block copolyimides could be easily attributed to the presence of alternate amide or ester linkages accompanied by imide groups in the polymer backbone. The ultraviolet maximum wavelength values of the yellowish polymers were determined from their ultraviolet spectra. The crystallinity of these copolyimides was estimated by means of wide-angle X-ray diffraction, and the resultant polymers exhibited a nearly amorphous nature, except for the polymers derived from benzidine and 4,4′-binaphthol. The poly (amide imide)s exhibited excellent solubility in a variety of highly polar aprotic solvents, whereas the poly(ester imide)s showed good solubility in less polar solvents. According to differential scanning calorimetry analyses, polymers 4a-4d and 5a-5d had glass-transition temperatures between 331 and 357°C and between 318 and 342°C, respectively. The thermal behaviors of the obtained polymers were characterized by thermogravimetric analysis, and the 10% weight loss temperatures of the poly(amide imide)s and poly(ester imide)s were between 579 and 604°C and between 566 and 577°C in nitrogen, respectively. © 2006 Wiley Periodicals, Inc.

A series of new alternating aromatic poly(ester-imide)s were prepared by the polycondensation of the preformed imide ring-containing diacids, 2,2′-bis(4-trimellitimidophenoxy)biphenyl (2a) and 2,2′-bis(4-trimellitimidophenoxy)-1,1′-binaphthyl (2b) with various aromatic dihydroxy compounds in the presence of pyridine and lithium chloride. A model compound (3) was also prepared by the reaction of 2b with phenol, its synthesis permitting an optimization of polymerization conditions. Poly(ester-imides) were fully characterized by FTIR, UV-vis and NMR spectroscopy. Both biphenylene- and binaphthylene-based poly(ester-imide)s exhibited excellent solubility in common organic solvents such as tetrahydrofuran, m-cresol, pyridine and dichloromethane. However, binaphthylene-based poly(ester-imide)s were more soluble than those of biphenylene-based polymers in highly polar organic solvents, including N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide and dimethyl sulfoxide. From differential scanning calorimetry thermograms, the polymers showed glass-transition temperatures between 261 and 315 °C. Thermal behaviour of the polymers obtained was characterized by thermogravimetric analysis, and the 10 % weight loss temperatures of the poly(ester-imide)s was in the range 449-491 °C in nitrogen. Furthermore, crystallinity of the polymers was estimated by means of wide-angle X-ray diffraction. The resultant poly(ester-imide)s exhibited nearly an amorphous nature, except poly(ester-imide)s derived from hydroquinone and 4,4′-dihydroxybiphenyl. In general, polymers containing binaphthyl units showed higher thermal stability but lower crystallinity than polymers containing biphenyl units. © 2005 Society of Chemical Industry.

A new aromatic dicarbonylazide (3) bearing three preformed imide rings was synthesized by treating N-[3,5-bis(trimellitimido)phenyl]phthalimide (1) with thionyl chloride followed by a nucleophilic reaction with sodium azide. A novel family of fully aromatic poly(urethane-imide)s with inherent viscosities of 0.19-0.24 dl g-1 were prepared from triimide-dicarbonylazide 3 and various aromatic diols. The polyaddition reactions readily proceeded in desirable yields as one-pot reactions starting from 3 without separately synthesis of the corresponding diisocyanate. All of the resulted polymers were thoroughly characterized by spectroscopic methods and elemental analyses. The poly(urethane-imide)s exhibited an excellent solubility in a variety of polar solvents. Crystallinity nature of the polymers was estimated by means of WXRD. The glass transition temperatures of the polymers determined by DSC method were in the range of 197-219 °C. The 10% weight loss temperatures of the poly(urethane-imide)s from their TGA/DTG curves were found to be in the range of 391-412 °C in nitrogen. The films of the polymers were also prepared by casting the solution. © 2005 Elsevier Ltd. All rights reserved.

A new dicarboxylic acid chloride (2) bearing three preformed imide rings was synthesized by treating N-(3,5-diaminophenyl)phthalimide with trimellitic anhydride followed by refluxing with thionyl chloride. A novel family of aromatic poly(ester-imide)s with inherent viscosities of 0.27-0.35 dl g -1 were prepared from 2 with various bisphenols such as resorcinol (3a), hydroquinone (3b), 2,2′-dihydroxybiphenyl (3c), 4,4′- dihydroxybiphenyl (3d), bisphenol-A (3e), 2,2′-dimethyl-4,4′- dihydroxybiphenyl (3f), 1,5-dihydroxynaphthalene (3g), 2,7-dihydroxynaphthalene (3h), and 2,2′-dihydroxy-1,1′-binaphthyl (3i) by high-temperature solution polycondensation in nitrobenzene using pyridine as hydrogen chloride quencher. All of the resulted polymers were fully characterized by FT-IR and NMR spectroscopy and elemental analyses. The poly(ester-imide)s exhibited excellent solubility in some polar organic solvents. From differential scanning calorimetry, the polymers showed glass-transition temperatures between 259 and 353 °C. Thermal behaviors of the obtained polymers were characterized by thermogravimetric analysis and the 10% weight loss temperatures of the poly(ester-imide)s were found to be in the range between 451 and 482 °C in nitrogen. Furthermore, crystallinity of the polymers was estimated by means of wide-angle X-ray diffraction. © 2005 Elsevier Ltd. All rights reserved.

New diimide-dicarboxylic acids, ie 4-phenyl-2,6-bis(4-trimellitimidophenyl)pyridine and 4p-biphenyl-2, 6-bis(4-trimellitimidophenyl)pyridine, were synthesized by the condensation reaction of 4-phenyl-2,6-bis(4-aminophenyl)pyridine and 4-p-biphenyl-2,6-bis(4-aminophenyl)pyridine with trimellitic anhydride in glacial acetic acid or dimethylformamide. The monomers were fully characterized by FT-IR and NMR spectroscopies, and elemental analyses. A series of novel poly(amide-imide)s with inherent viscosities of 0.68-0.87 d1g-1 was prepared from the two diimide-diacids with various aromatic diamines by direct polycondensation. The poly(amide-imide)s were characterized by FT-IR and NMR spectroscopies. The λmax data for the resulting poly(amide-imide)s were in the range of 260-292 nm. These polymers exhibited good solubilities in polar aprotic solvents. The 10 % weight loss temperatures are above 485°C under a nitrogen atmosphere. © 2004 Society of Chemical Industry.

A new dicarboxylic acid, N-[3,5-bis(N-trimellitoyl)phenyl]phthalimide (1a), bearing three preformed imide rings was synthesized from the condensation of N-(3,5-diaminophenyl)phthalimide and trimellitic anhydride in glacial acetic acid at 1:2 molar ratio. For study of structure-properties relationship 1,3-bis(N-trimellitoyl)benzene (1b, as a reference) was also synthesized in a similar manner. 1a and 1b were characterized by spectroscopic methods and elemental analyses. A series of wholly aromatic poly(amide-imide)s with inherent viscosities of 0.63-1.09 dlg-1 was prepared by triphenyl phosphite-activated polycondensation from the triimide-dicarboxylic acid 1a and the reference monomer 1b with various aromatic diamines. All of the polymers were fully characterized by FT-IR and 1H NMR spectroscopy. The effects of the phthalimide pendent group on the polymers properties such as solubility, crystallinity, and thermal stability were investigated by comparison of the polymers. The polymers obtained from triimide-dicarboxylic acid 1a exhibited excellent solubility in a variety of solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, and dimethylsulfoxide. These poly(amide-imide)s possessed glass-transition temperatures from 334 to 403 °C and exhibited excellent thermal stabilities and had 10% weight losses from 541 to 568 °C under a nitrogen atmosphere. Poly(amide-imide)s containing phthalimide pendent groups showed higher solubility, higher Tg and Td10% values than those having no phthalimide pendent groups. © 2004 Elsevier Ltd. All rights reserved.

New aromatic diimide-dicarboxylic acids having kinked and cranked structures, 2,2′-bis(4-trimellitimidophenoxy) biphenyl (2a) and 2,2′-bis(4-trimellitimidophenoxy)-1,1′-binaphthyl (2b), were synthesized by the reaction of trimellitic anhydride with 2,2′-bis(4-aminophenoxy)biphenyl (1a) and 2,2′-bis(4-aminophenoxy)-1,1′-binaphthyl (1b), respectively. Compounds 2a and 2b were characterized by FT-IR and NMR spectroscopy and elemental analyses. Then, a series of novel aromatic poly(amide-imide)s were prepared by the phosphorylation polycondensation of the synthesized monomers with various aromatic diamines. Owing to structural similarity, and a comparison of the characterization data, a model compound was synthesized by the reaction of 2b with aniline. The resulting polymers with inherent viscosities of 0.58-0.97 dl g-1 were obtained in high yield. The polymers were fully characterized by FT-IR and NMR spectroscopy. The ultraviolet λmax values of the poly (amide-imide)s were also determined. The polymers were readily soluble in polar aprotic solvents. They exhibited excellent thermal stabilities and had 10% weight loss at temperatures above 500°C under a nitrogen atmosphere. © 2003 Society of Chemical Industry.