Preparation and characterization of castor oil‐based polyurethane/poly(o‐methoxyaniline) blend film

Blends made up of castor oil‐based polyurethane (PU) and poly(o‐methoxyaniline) (POMA) were obtained in the form of films by casting and characterized by FTIR, UV‐Vis‐NIR spectroscopy, and electrical conductivity measurements. Doping was carried out by immersing the films in 1.0M HCl aqueous solution. Chemical bonds between NCO group of PU and NH group of POMA were observed by means of FTIR spectra. The UV‐Vis‐NIR spectra indicated that the presence of the PU in the blend does not affect doping and formation of the POMA phase. The electrical conductivity research was in the range of 10^?3 S/cm. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Copolymers of aniline and o‐methoxyaniline: Synthesis and characterization

High‐conversion (HC) copolymers of aniline and o‐methoxyaniline (o‐anizidine) were synthesized for the first time by chemical oxidative copolymerization by using various polymerization techniques (simultaneous or consecutive introduction of comonomers into the polymerizing system). Low‐conversion (LC) copolymers have also been synthesized for comparison. The polymers obtained were characterized by using ¹H‐NMR, infrared, and electronic absorption spectroscopy; differential scanning calorimetry; and electrical conductivity measurements. Solubility characteristics and composition of different fractions of the copolymers were also determined. It was shown that, in contrast to the LC copolymers, HC copolymers reveal relatively poor solubility. Electrical conductivity of copolymers and also of o‐methoxyaniline homopolymer is lower as compared to polyaniline, which correlates with notable hypsochromic (blue) shift of the bands in electronic absorption spectra. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1822–1828, 2005     

Copolymers of aniline and o‐methoxyaniline: Synthesis and characterization

High‐conversion (HC) copolymers of aniline and o‐methoxyaniline (o‐anizidine) were synthesized for the first time by chemical oxidative copolymerization using various polymerization techniques (simultaneous or consecutive introduction of comonomers into the polymerizing system). Low‐conversion (LC) copolymers have also been synthesized for comparison. The polymers obtained were characterized using ¹H‐NMR, infrared, and electronic absorption spectroscopy, differential scanning calorimetry, and electrical conductivity measurements. Solubility characteristics and composition of different fractions of the copolymers were also determined. It was shown that in contrast to the LC copolymers, HC copolymers reveal relatively poor solubility. Electrical conductivity of copolymers and also of o‐methoxyaniline homopolymer is lower compared to polyaniline, which correlates with notable hypsochromic (blue) shift of the bands in electronic absorption spectra. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 75–81, 2006     

Copolymers of aniline with o‐ and m‐toluidine: synthesis and characterization

Copolymers of aniline and toluidine were synthesized by oxidative chemical polymerization using different ratios of the monomers in the feed, and characterized by a number of techniques including UV–visible, IR, Raman, ¹H NMR and EPR spectroscopies, as well as by thermogravimetric analysis and conductivity measurements. The properties of the copolymers are influenced by the amount of toluidine in the copolymer. Poly(o‐toluidine) and poly(m‐toluidine) are noticeably different in their solubility and conductivity. The copolymers show better solubilities than polyaniline but have lower conductivities. Differences in the properties of the salt and base forms of the copolymers are pointed out. Copyright © 2003 Society of Chemical Industry     

Studies on the dielectric properties of poly(o‐toluidine) and poly(o‐toluidine‐aniline) copolymer

Poly(o‐toluidine) (PoT) and poly(o‐toluidine co aniline) were prepared by using ammonium persulfate initiator, in the presence of 1M HCl. It was dried under different conditions: room temperature drying (48 h), oven drying (at 50°C for 12 h), or vacuum drying (under vacuum, at room temperature for 16 h). The dielectric properties, such as dielectric loss, conductivity, dielectric constant, dielectric heating coefficient, loss tangent, etc., were studied at microwave frequencies. A cavity perturbation technique was used for the study. The dielectric properties were found to be related to the frequency and drying conditions. Also, the copolymer showed better properties compared to PoT alone. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 592–598, 2004     

Influence of various reaction media on the thermal and rheological properties of poly(acrylamide‐co‐N‐hexadecylacrylamide)

A hydrophobically modified polyacrylamide (PAM) was synthesized by the copolymerization of acrylamide (Am) and N‐hexadecylacrylamide (hAm) through solution copolymerization in a polar organic solvent. Polymer synthesis was performed in three nonaqueous media, including dimethyl sulfoxide (DMSO), a mixture of DMSO and an anionic surfactant such as sodium dodecyl sulfate, and a mixture of DMSO and an acidic surfactant such as dodecyl benzene sulfonic acid. The obtained copolymer, poly(acrylamide‐co‐N‐hexadecylacrylamide) [poly(Am‐co‐hAm)], was characterized by ¹H‐NMR. The physical properties of poly(Am‐co‐hAm)s synthesized in different media were compared with those of PAM and with each other by viscosity measurement, X‐ray diffraction, thermogravimetric analysis, and differential scanning calorimetry. We investigated the ways in which the polymerization medium affected the hydrophobic distribution within the resulting copolymer structure. This aspect, in turn, should have altered the solution properties and the microstructure of the copolymer. For this purpose, we studied the viscometric behavior in diluted solutions, the thermal behavior and thermal stability of the copolymers, and finally, the crystalline structure of the copolymers. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014 , 131, 39939.     

Chemical copolymerization of aniline with o‐chloroaniline: thermal stability by spectral studies

Poly(aniline‐co‐o‐chloroaniline) salts were synthesized by chemical copolymerization of aniline with o‐chloroaniline using three different acids. The polymer salt samples were heat treated at four different temperatures (150, 200, 275 and 375 °C) and the thermal stability of the polymer salts were studied by conductivity, electron paramagnetic resonance (EPR), infrared (IR) and electronic absorption spectral measurements. The conductivity of the copolymers could be controlled in a broad range from 10 S cm⁻¹ for homopolymer of aniline to 10⁻⁴ S cm⁻¹ for those of o‐chloroaniline. No structural changes took place up to 200 °C and this was confirmed from EPR, IR and electronic absorption spectra. No definite correlation exists between conductivity and spin concentration. © 2000 Society of Chemical Industry     

Comparison of poly(o‐anisidine) and poly(o‐anisidine‐co‐aniline) copolymer synthesized by chemical oxidative method

In this study, poly(o‐anisidine) [POA], poly(o‐anisidine‐co‐aniline) [POA‐co‐A], and polyaniline [PANi] were chemically synthesized using a single polymerization process with aniline and o‐anisidine as the respective monomers. During the polymerization process, p‐toluene sulfonic acid monohydrate was used as a dopant while ammonium persulfate was used as an oxidant. N‐methyl‐pyrolidone (NMP) was used as a solvent. We observed that the ATR spectra of POA‐co‐A showed features similar to those of PANi and POA as well as additional ones. POA‐co‐A also achieved broader and more extended UV–vis absorption than POA but less than PANi. The chemical and electronic structure of the product of polymerization was studied using Attenuated Total Reflectance spectroscopy (ATR) and UV–visible spectroscopy (UV–vis). The transition temperature of the homopolymers and copolymers was studied using differential scanning calorimetry and the viscosity average molecular weight was studied by using dilute solution viscometry. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Photocarrier mobility in poly(2‐methoxyaniline)

In the current study the mobility of photogenerated charge carriers in PMA [poly(2‐methoxyaniline)] and their transport were investigated using time‐of‐flight (TOF) techniques. Also studied was the effect on hole mobility of film thickness and of the method of polymer processing during device fabrication. The highest value of hole mobility found was 4.5 × 10⁻⁴ cm² V⁻¹ s⁻¹ at an applied field of 1.3 × 10⁶ V/cm and 293 K in solution‐cast film of PMA. The hole mobility of solution‐cast films was about 2 orders of magnitude higher compared to spin‐coated films, for which the ordering of the polymer chains may be the reason. To our knowledge, this is the first time the TOF mobility of this material has been presented. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 1506–1512, 2001     

Preparation and characterization of di‐hexadecanol maleic/triallyl isocyanurate cross‐linked copolymer as solid–solid phase change materials

Di‐hexadecanol maleic/Triallyl isocyanurate cross‐linked copolymers as a novel solid–solid phase change materials were successfully synthesized through bulk polymerization. TAIC is the skeleton and DM is a functional side chain that stores and releases heat during its phase transition process. Fourier transform infrared spectroscopy, wide‐angle X‐ray diffraction, polarizing optical microscopy, differential scanning calorimetry, and thermogravimetry were employed to study the composition, chemical structure, crystalline properties, phase transition behaviors, and the thermal stability of the cross‐linked copolymers, respectively. The test results indicate that DM/TAIC cross‐linked copolymers have good thermal reliability and heat storage durability after 500 thermal cycles. The phase change temperatures of DM/TAIC cross‐linked copolymers were approximately 28.24–37.02°C, and it has high latent heat storage capacity of more than 83 J/g. At the same time, DM/TAIC cross‐linked copolymers have good thermal stability, and they can be processed or used in high temperature environments. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44065.     

Heterocyclic‐based epoxy‐terminated structural adhesive. II. Curing,adhesive strength,and thermal stability

We studied the curing behavior of heterocyclic‐based epoxy‐terminated resins using diaminodiphenyl ether, diaminodiphenyl sulfone, benzophenone tetracarboxylicdianhydride, and the commercial hardener of Ciba‐Geigy's two‐pack Araldite as curing agents. The adhesive strength of the adhesives was measured by various ASTM methods such as lap‐shear, peel, and cohesive tests on metal–metal, wood–wood, and wood–metal interfaces. All of these results were compared with those of an epoxy resin prepared from bisphenol‐A and epichlorohydrin resin with an epoxy equivalent value of 0.519. The thermal stability of both the virgin resin and its cured form was also studied by thermogravimetric analysis. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3520–3526, 2002     

Synthesis and characterization of poly(o‐anisidine)/V2O5 and poly(o‐anthranilic acid)/V2O5 nanocomposites

Poly(o‐anisidine)/V₂O₅ and poly(o‐anthranilic acid)/V₂O₅ nanocomposites were prepared by in situ intercalative polymerization, and the structure and electrical properties of these nanocomposites were investigated using GPC, TGA, XRD, TEM, FTIR, UV‐vis as well as conductivity measurement. The results show that the steric effect and nature of the substituting groups in the aromatic ring has an influence on the structure and electrical properties of the nanocomposites. Poly(o‐anisidine) or poly(o‐anthranilic acid) exists as a monolayer of outstretched chains in the gallery of the V₂O₅ xerogel owing to the confined environment in the nanometer‐size gallery. And intercalation of poly(o‐anisidine) or poly(o‐anthranilic acid) can improve the conductivity of V₂O₅ xerogel. Copyright © 2005 Society of Chemical Industry     

Synthesis and electrical properties of copolymers of o‐phenylenediamine with aniline, 3,4‐ethylenedioxythiophene and 2,3,5,6‐tetrafluoroaniline

Copolymers (P(PDA/Ar)) of o‐phenylenediamine with aniline (Ar = ANi), 3,4‐ethylenedioxythiophene (Ar = EDOT) and 2,3,5,6‐tetrafluoroaniline (Ar = TFANi) were synthesized via polycondensation initiated by ammonium persulfate. The NH₂ group content in the copolymers was determined by analyzing the ¹H NMR spectra of the N‐acetylated copolymers. Copolymers crosslinked by viologen (1,1'‐disubstituted 4,4'‐bipyridinium dichloride) were obtained by reaction involving the reactive NH₂ groups in the copolymers. The absorption wavelengths of solutions of the copolymers and the electrochemical oxidation and reduction potentials of cast films of the copolymers were affected by the electrical properties of the Ar unit. © 2016 Society of Chemical Industry     

Poly(O‐methoxyaniline) thin films: Cyclic voltammetry study

Electrochemical polymerization of poly(O‐methoxyaniline) (POMA) thin films was carried out under cyclic voltammetric conditions. The cyclic voltammograms (CV) of the POMA films in the presence and absence of monomer in the aqueous solution of 1M H₂SO₄ were studied. The electrochemical degradation of the POMA films was investigated by cyclic voltammetry and UV‐visible spectroscopy. It was observed that the rate of degradation is strongly dependent on the applied potential. UV‐visible spectroscopy revealed no significant chemical modification or phase change from the degradation. The temperature dependence of the voltammetric response of the POMA films in the aqueous solution of 1M H₂SO₄ was also investigated. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 3009–3015, 1999     

Crystallization kinetics of poly(1,4‐butylene‐co‐ethylene terephthalate)

The crystallization kinetics of poly(butylene terephthalate) (PBT), poly(ethylene terephthalate) (PET), and their copolymers poly(1,4‐butylene‐co‐ethylene terephthalate) (PBET) containing 70/30, 65/35 and 60/40 molar ratios of 1,4‐butanediol/ethylene glycol were investigated using differential scanning calorimetry (DSC) at crystallization temperatures (T_c) which were 35–90 °C below equilibrium melting temperature . Although these copolymers contain both monomers in high proportion, DSC data revealed for copolymer crystallization behaviour. The reason for such copolymers being able to crystallize could be due to the similar chemical structures of 1,4‐butanediol and ethylene glycol. DSC results for isothermal crystallization revealed that random copolymers had a lower degree of crystallinity and lower crystallite growth rate than those of homopolymers. DSC heating scans, after completion of isothermal crystallization, showed triple melting endotherms for all these polyesters, similar to those of other polymers as reported in the literature. The crystallization isotherms followed the Avrami equation with an exponent n of 2–2.5 for PET and 2.5–3.0 for PBT and PBETs. Analyses of the Lauritzen–Hoffman equation for DSC isothermal crystallization data revealed that PBT and PET had higher growth rate constant G_o, and nucleation constant K_g than those of PBET copolymers. © 2001 Society of Chemical Industry     

Synthesis and Thermal Characterization of Some Novel ABA Block Copolymers

The synthesis of some novel ABA block copolymers is reported. The block A is a PPO while the block B is a random copoly(aryl ether sulfone), synthesized with three different molecular weights. The block copolymers were obtained by a two step procedure consisting on the functionalization of the random copoly(aryl ether sulfone) followed by a condensation with PPO. Spectroscopic techniques (¹H NMR and ¹³C NMR) were used to characterize the polymers obtained from each step. The NMR data proved the complete conversion of amino groups after the first reaction step and gave some useful insights on the completion of the second step. Copolymer formation is supported by a comparison of the thermal behavior of the block copolymers with respect to the physical blends of the two homopolymers. DSC and DMA analyses showed double glass transitions for the physical blends which could be related to the immiscibility of the two homopolymers, while, in contrast, the block copolymer showed single glass transition. Blends of ABA triblock copolymer/PPO and of ABA triblock/copoly(arylen ether sulfone)s were also prepared. These blends, tested by DSC, showed a good level of compatibility of the ABA copolymer with its singular constituents.

     

Chemical grafting of aniline and o‐toluidine onto poly(ethylene terephthalate) fiber

Graft copolymerization of poly(aniline) and poly(o‐toluidine) onto poly(ethylene terephthalate) fiber was conducted by using peroxydisulfate as a lone initiator under nitrogen atmosphere at various experimental conditions in aqueous hydrochloric acid medium. The grafting of poly(aniline) and poly(o‐toluidine) onto poly(ethylene terephthalate) fiber was verified by recording cyclic voltammetry of the grafted fiber, conductivity measurements, and thermal analysis. Graft parameters—such as % grafting, % efficiency, and the rate of grafting—were followed. Grafting was always accompanied by homopolymerization. The rate of homopolymerization was also followed in all experimental conditions. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 121–128, 1999     

Characterization of biodegradable polymers by inverse gas chromatography. II. Blends of amylopectin and poly(ε‐caprolactone)

Amylopectin (AP), a potato‐starch‐based polymer with a molecular weight of 6,000,000 g/mol, was blended with poly(ε‐caprolactone) (PCL) and characterized with inverse gas chromatography (IGC), differential scanning calorimetry (DSC), and X‐ray diffraction (XRD). Five different compositions of AP–PCL blends ranging from 0 to 100% AP were studied over a wide range of temperatures (80–260°C). Nineteen solutes (solvents) were injected onto five chromatographic columns containing the AP–PCL blends. These solutes probed the dispersive, dipole–dipole, and hydrogen‐bonding interactions, acid–base characteristics, wettability, and water uptake of the AP–PCL blends. Retention diagrams of these solutes in a temperature range of 80–260°C revealed two zones: crystalline and amorphous. The glass‐transition temperature (T_g) and melting temperature (T_m) of the blends were measured with these zones. The two zones were used to calculate the degree of crystallinity of pure AP and its blends below T_m, which ranged from 85% at 104°C to 0% at T_m. IGC complemented the DSC method for obtaining the T_g and T_m values of the pure AP and AP–PCL blends. These values were unexpectedly elevated for the blends over that of pure AP and ranged from 105 to 152°C for T_g and from 166 to 210°C for T_m. The T_m values agreed well with the XRD analysis data. This elevation in the T_g and T_m values may have been due to the change in the heat capacity at T_g and the dependence of T_g on various variables, including the molecular weight and the blend composition. Polymer blend/solvent interaction parameters were measured with a variety of solutes over a wide range of temperatures and determined the solubility of the blends in the solutes. We were also able to determine the blend compatibility over a wide range of temperatures and weight fractions. The polymer–polymer interaction coefficient and interaction energy parameter agreed well on the partial miscibility of the two polymers. The dispersive component of the surface energy of the AP–PCL blends was measured with alkanes and ranged from 16.09 mJ/m² for pure AP to 38.26 mJ/m² when AP was mixed with PCL in a 50/50% ratio. This revealed an increase in the surface energy of AP when PCL was added. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3076–3089, 2006     

Preparation and fluorescence properties of poly(o‐methyl‐acrylamideyl‐benzoic acid)‐ZnS composites

Poly(o‐methyl‐acrylamideyl‐benzoic acid)‐ZnS (P(o‐MAABA)‐ZnS) nanocomposites have been prepared and characterized. The resultant P(o‐MAABA)‐ZnS nanocomposites in solution show two emissions in the purple‐light area (370 nm) and in the blue‐light area (425 nm), which are assigned to the polymer and ZnS nanoparticles, respectively. The coordination between the polymer and Zn²⁺ and the surface chemical composition has been studied by Infrared spectroscopy and X‐ray photoelectron spectroscopy (XPS). The particle size of ZnS nanoparticles was homogeneous and the average size was 3.8 nm, which were characterized by UV absorption spectrum and X‐ray Diffraction. The P(o‐MAABA)‐ZnS composites displays good film formability and the films also show two emissions in 370 and 425 nm. After doped with Tb³⁺, there was effective energy transfer from ZnS nanoparticles to Tb³⁺. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Helical opposition in poly(2‐methoxyaniline) by tuning the concentration of salts in reaction solution

The synthesis and application of helical polyaniline derivatives (PANIs) have attracted much interest. However, most of these syntheses have been carried out in organic solutions. In our previous reports, helical PANIs were successfully realized in aqueous solution. Because helical architecture in the backbones of PANIs is an induced rather than the natural arrangement, it is significant to study the change in helicity in aqueous solution, especially opposition or reversion. One excess‐handed helicity was induced in poly(2‐methoxyaniline) (PMOA) by electrochemical polymerization of 2‐methoxyaniline at pH = 2.5 in the presence of protonated β‐cyclodextrin sulfate (CDS^? H⁺). When 0.04 mol L^?1 NaCl was added to the reaction solution, the PMOA backbone took on an opposite excess of one‐handed helicity, which was confirmed by induced circular dichroism. Such a result originates from the dynamic switch between electrostatic and hydrogen‐bonding interactions. The helix‐inducing process in PMOA depends on the interaction between PMOA and chiral CDS. Due to the competition of Na⁺ Cl^? with PMOA⁺ CDS^?, the electrostatic interaction between PMOA and CDS is limited or weakened. Thus, the slightly preferred interaction between them switches from electrostatic to hydrogen bonding. Simultaneously, the interaction positions and distance are changed. The changed steric hindrance induces PMOA into adopting an opposite excess‐handed helicity. Copyright © 2010 Society of Chemical Industry