Solubility Of Poly Research Articles

Synthesis and spectral characterizations of electroluminescent poly(2,3-di-[ p-(2′-ethylhexoxy)phenyl]-1,4-phenylenevinylene)

By means of chemical modification, flexible branched alkoxy chains were successfully attached to the para-site of the side phenyl groups of DP-PPV to obtain a new soluble fully conjugated PPV, named poly(2,3-di-[ p-(2′-ethylhexoxy)phenyl]-1,4-phenylenevinylene). Spectroscopic characterizations using UV, photoluminescence (PL) and photoluminescent excitation (PLE) showed only the emission of single chromophore of this polymer in the solution state, indicating that the solubility of poly(2,3-diphenyl-1,4-phenylene vinylene) (DP-PPV) was significantly improved by attaching the alkoxy side chains. In the spin-coated film, the emission of the single chromophore with longer conjugating length was observed. In addition, the spectral feature showed the absence of the emission from the aggregate, which was usually observed in the alkoxy-modified PPV, revealing that the polymer chains were well-separated by the side chains. The performance of the single-layer ITO/PEDOT/ p-EHDP-PPV/Ca/Al LED device was also reported. The maximum luminescence and efficiency at 11 V was 3735 Cd/m 2 and 0.57 Cd/A, respectively.

I-Shaped Microchannel Array Chip for Parallel Electrophoretic Analyses

We demonstrate electrophoresis in I-shaped microchannels with a new design and operation principle. Unlike the conventional T- or cross-shaped microchannels, the simple I-shaped design makes it straightforward to integrate parallel microchannels with electrodes onto a microchip. The operation of the I-shaped microchannels has been enabled by the autonomous solution filling technique, which exploits the high gas solubility in poly(dimethylsiloxane) (PDMS). We fabricated an I-shaped microchannel array (IMA) chip by integrating 12 independent microchannels and 2 electrodes onto a 3 cm x 2 cm area in a PDMS-glass hybrid microchip. For autonomous regulation of stable sample plugs in all the microchannels, we discovered that O2 plasma treatment of the PDMS-made reservoirs is effective. On the IMA chip, size-dependent separation of double-stranded (ds) DNA and sequence-specific separation of single-stranded DNA were achieved. Specifically, 10 fragments in a 100-1000-bp dsDNA ladder were separated using hydroxyethylcellulose as a sieving matrix within a separation length of 2 mm, and polymerase chain reaction products of the wild-type K-ras gene and its point mutant were separated using a probe DNA-poly(dimethylacrylamide) conjugate on the basis of affinity capillary electrophoresis. The IMA chip presented here opens up a new possibility of large-scale integration of microchannels for high-throughput electrophoretic analyses.

Synthesis of optically active poly(N‐propargylsulfamides) with helical conformation

AbstractA novel chiral N‐propargylsulfamide monomer (1a) and its enantiomer (1b) were synthesized and polymerized with (nbd)Rh+B−(C6H5)4 as a catalyst providing poly(1) (poly(1a) and poly(1b)) in high yields (≥99%). Poly(1) could take stable helices in less polar solvents (chloroform and THF), demonstrated by strong circular dichroism signals and UV–vis absorption peaks at about 415 nm and the large specific rotations; but in more polar solvents including DMF and DMSO, poly(1) failed to form helix. Quantitative evaluation with anisotropy factor showed that the helical screw sense had a relatively high thermal stability. These results together with the IR spectra measured in solvents showed that hydrogen bonding between the neighboring sulfamide groups is one of the main driving forces for poly(1) to adopt stable helices. In addition, copolymerization of monomer 1a and monomer 2 was conducted, the solubility of poly(1) was improved drastically. However, the copolymerization had adverse effects on the formation of stable helices in the copolymers. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 500–508, 2007

Gas Diffusion and Solubility in Poly(organophosphazenes): Results of Molecular Simulation Studies

A combination of quantum chemistry, molecular dynamics, and Monte Carlo methods have been used to investigate gas diffusion and solubility in three isomeric poly[di(butoxyphosphazenes)] and in amorphous and crystalline states of poly[bis(2,2,2-trifluoroethoxyphosphazene)] (PTFEP). In this review of recently published studies reported from our laboratory, conclusions are reached in regards to the relationship between polymer structure and gas diffusion and sorption in poly(organophosphazenes). These conclusions also serve to validate our current understanding of the nature of gas transport in other polymers. Specifically, gas diffusivity has been shown to increase with increasing side-chain and main-chain mobility as determined from vectorial autocorrelation function analysis; however, high diffusivity is accompanied by a loss in diffusive selectivity resulting in decreasing permselectivity with increasing permeability. Simulation of crystalline supercells of PTFEP indicate that gas diffusion is unrestricted in the crystalline state as has been reported only for a few other polymers, principally poly(4-methyl-1-pentene). Gas solubility in poly(organophosphazenes) correlates well with gas condensability as measured by the Lennard–Jones potential well depth parameter, ɛ/k. Exceptions are cases where specific interactions can occur between gas molecules and the polymer chain such as is the case of CO2 and PTFEP. High-level ab initio calculations of the interaction of CO2 with low-molecular-weight fluoroalkanes indicate the presence of a weak quadrupole–dipole interaction. Association of CO2 with the trifluoromethyl groups of the trifluoroethoxy side chain of PTFEP has been confirmed by radial distribution function (RDF) analysis of MD trajectories. Comparison between solubility coefficients obtained from Grand Canonical Monte Carlo (GCMC) simulations of amorphous cells with experimental values of microcrystalline PTFEP indicates that gas solubility in polyphosphazenes such as PTFEP that exhibit a mesophase/crystalline state is greatly reduced.

Coacervation Microencapsulation of Talc Particles with a Fluoropolymer by Pressure-Induced Phase Separation of Supercritical Carbon Dioxide Solutions

We report a method for the coacervation microencapsulation of talc (Mg 3 Si 4 O 10 (OH) 2 ) microparticles with the fluoropolymer poly(heptadecafluorodecyl acrylate) (poly(HDFDA)) by pressure-induced phase separation of a supercritical CO 2 solution. A suspension of talc in CO 2 and dissolved poly(HDFDA) were mixed in supercritical CO 2 . After the system pressure was slowly decreased to atmospheric pressure, the microcapsules were obtained in a high-pressure cell. Coacervation was achieved by the precipitation of poly(HDFDA) during the decrease in the pressure of CO 2 ; the solubility of poly(HDFDA) in CO 2 decreased with the pressure. The structure and morphology of the microparticles were investigated by using a scanning electron microscope (SEM) and an electron probe microanalyzer (EPMA) equipped with a wavelength dispersive X-ray spectroscope (WDX). This investigation revealed that the talc was thoroughly coated with poly(HDFDA). Furthermore, the effects of experimental conditions such as the depressurizing rate, polymer concentration, and temperature on particle morphology were investigated.

Poly(4-nitrophenyl)quinoxalines

Via the reaction of 4,4-bis(4-nitrophenylglyoxalyl)diphenyl ether with different bis(o-phenylenediamine)s, new poly(4-nitrophenyl)quinoxalines were synthesized, which are of interest as precursors for polymers containing protogenic groups. Some properties of the obtained polymers were studied. It was shown that the solubility of poly(4-nitrophenyl)quinoxalines in organic solvents and their viscosity characteristics are comparable with the parameters of polyphenylquinoxalines that do not bear nitro groups. A study of the thermal properties of the polymers showed that the introduction of nitro groups into polyphenylquinoxalines is accompanied by some increase in the glass transition temperature and a decrease in the onset temperature of runaway thermal degradation.

Nitrogen permeability and carbon dioxide solubility in poly(1-trimethylsilyl-1-propyne)-based binary substituted polyacetylene blends

The nitrogen permeability and carbon dioxide solubility in poly(1-trimethylsilyl-1-propyne) (PTMSP)/poly(4-methyl-2-pentyne) (PMP) blends were studied and compared with previously reported values for PTMSP/poly( tert-butylacetylene) (PTBA) and PTMSP/poly(1-phenyl-1-propyne) (PPP) blends. The nitrogen permeability of the homopolymers follows the order: PTMSP > PMP > PTBA > PPP. This order is the same as that of their fractional free volumes, that is, the permeability of the polymers decreases with decreasing fractional free volume. The permeability of the blends obeys a simple mixing rule for homogeneous binary polymer blends. As expected, the nitrogen permeability of PTMSP/PMP blends decreases with increasing PMP content in the blend. The carbon dioxide solubility in the homopolymers follows the order: PTMSP > PMP > PTBA > PPP. This order is the same as that of the nitrogen permeability of the polymers. The carbon dioxide solubility in PTMSP/PMP blends also decreases with increasing PMP content. The sorption isotherms of PTMSP/PMP blends were analyzed based on a dual-mode sorption mechanism. The Langmuir-type solubility contributes to about 85% of the infinite dilution solubility in all PTMSP/PMP blends regardless of the PMP content. A linear correlation is observed between the nitrogen permeability and the reciprocal Langmuir capacity parameter ( C′ H ) for PTMSP-based binary blends, regardless of the blend co-component (i.e., PMP, PTBA, and PPP). Physical aging significantly reduces the nitrogen permeability of PTMSP. Relaxation of the non-equilibrium excess free volume induces a decrease in C′ H and, therefore, a decline in permeability. The permeability of the three blends showed significantly improved long-term stability compared with that of PTMSP. The permeability in all blends decreases linearly with increasing the reciprocal C′ H value. Hence, the permeability of PTMSP/substituted polyacetylene binary blends (i.e., PTMSP/PMP, PTMSP/PTBA, and PTMSP/PPP blends) can be correlated to the non-equilibrium excess free volume, regardless of the blend co-component (i.e., PMP, PTBA, and PPP).

Fractionation and ammonolytic degradation of poly(hexamethylene carbonate) in (supercritical) ammonia

Abstract Solubility, fractionation by extraction as a function of temperature, and ammonolysis of α-hydro-ω-hydroxy-poly(oxycarbonyloxyhexane-1,6-diyl) in liquid and supercritical ammonia have been studied. Up to 120°C, the solubility of poly- (hexamethylene carbonate) increases with temperature without significant ammonolytic cleavage. Above the critical temperature of ammonia, solubility and molar mass of the solute decrease as ammonolysis becomes more and more important. The molar mass of the extracted and residual polymer decreases with temperature under supercritical conditions. Adjusting residence time and reactivity through temperature and flow rate enables controlled ammonolysis to constant molar mass. Kinetics of dihexyl carbonate and hexyl carbamate shows that ammonolysis of the carbamate is much faster than of dihexyl carbonate.

Solvation of poly(methyl acrylate) and poly(vinyl acetate) by CO2 studied via atomistic Monte Carlo simulation techniques

Abstract The differences in solubility of poly(vinyl acetate) (PVAc) and poly(methyl acrylate) (PMA) were addressed by applying atomistic Monte Carlo simulation techniques. Polymer segments consisting of nine monomer units serve as model compounds for polymer chains. As a measure of intermolecular interactions with the solvent environment, cohesion energies of the polymer segments embedded in either the corresponding monomer or in CO2 were calculated. Only in case of PMA segments in CO2 environment, specific interactions between polymer segments were identified. This finding is in agreement with experimental results on phase behaviour and propagation kinetics.

Synthesis and solubility of poly(N‐methylbenzimidazole) and poly(N‐ethylbenzimidazole): control of degree of alkylation

AbstractIn this paper, synthesis of poly(N‐methylbenzimidazole) (PNMBI) and poly(N‐ethylbenzimidazole) (PNEBI) with various alkylation degrees was achieved by adding enough LiH and controlling the amount of substituting reactant. The degree of substituted methyl or ethyl was determined by elemental analysis. Changes in infrared spectroscopy due to nature and degree of substitution can clearly be found. With the modification of PBI, the solubility of PNMBI and PNEBI is improved significantly. There is no significant change of chemical structure of PNMBI after 0.5 h thermal treatment in both N2 and air at a temperature lower than 250 °C. Compared with PBI, the methanol permeability of PNMBI and PNEBI is a little higher but still of the same order of magnitude. Copyright © 2004 Society of Chemical Industry

Solvents effect on the physical properties of semi-dilute poly(N-isopropyl acryl amide) solutions

The physical properties of 5wt% poly(NIPAM) (Mv=3.22×105) semi-dilute solutions in H2O, D2O, and THF (tetrahydrofuran) solvents were studied using dynamic light scattering (DLS) and dynamic shear viscosity (DSV) measurements. The DLS data showed that there were poly(NIPAM) slow mode inter-polymer chains associations in H2O and D2O solvents. However, no DLS slow mode was observed in poly(NIPAM)/THF solutions. The DSV data showed that there are shear thickening behavior in these three poly(NIPAM) solutions, resulting in a maximum shear viscosity ηpeak in the viscosity η′(ω) versus shear frequency ω curve. The slow mode hydrodynamic radius 〈Rhs〉 of DLS measurements and the zero shear rate viscosity η0 and maximum viscosity ηpeak data of DSV measurements from poly(NIPAM)/H2O and poly(NIPAM)/D2O solutions show two critical transition temperatures with Tcr1=30–32°C and Tcr2=32–34°C. Poly(NIPASM)/D2O has higher Tcr1 and Tcr2 than poly(NIPASM)/H2O. However, no transition temperatures of poly(NIPAM)/THF solution were observed. The different temperature dependencies of these three solutions were attributed to the ‘solubility’ and ‘hydrogen bonding’ effects between poly(NIPAM) with H2O, D2O, and THF solvents. Without considering the polymer-solvent hydrogen bonding, the solubility of poly(NIPAM) in solvents decreases in the following sequence: THF>H2O>D2O and the degree of polymer-solvent hydrogen bonding increases in the following sequence: THF<H2O<D2O. The effects of the degree of ‘hydrogen bonding’ and the ‘solubility’ of polymer in solvents on the physical properties of poly(NIPAM) solutions are discussed.

Molecular weight fractionation of poly(methyl methacrylate) using Gas Anti-Solvent techniques

The solubility of poly(methyl methacrylate) in acetone, expanded by carbon dioxide, was studied at 20 °C for a variety of molecular weights and architectures. The suitability of the Gas Anti-Solvent method for fractionation of poly(methyl methacrylate) was investigated with positive results. The threshold pressure for precipitation of various monodisperse molecular weights was investigated, and the effectiveness of this technique to fractionate a polymer with a broad molecular weight distribution was evaluated. The pressure required to precipitate polymers was found to be low, generally below 60 bar.

Synthesis and properties of some novel, soluble and light‐coloured, aromatic poly(amide–imide) copolymers

AbstractA new type of tetraimide‐dicarboxylic acid (I) was synthesized starting from the ring‐opening addition of m‐aminobenzoic acid (m‐ABA), 4,4′‐oxydiphthalic anhydride (ODPA) and 4,4′‐methylenedianiline (MDA) at a 2:2:1 molar ratio in N‐methyl‐2‐pyrrolidone (NMP), followed by cyclodehydration to the diacid I. A series of soluble and light‐coloured poly(amide–imide–imide)s (IIIa–j) was prepared by triphenyl phosphite‐activated polycondensation from the tetraimide‐diacid I with various aromatic diamines (IIa–j). All films cast from DMAc had cutoff wavelengths shorter than 400 nm (376–393 nm) and had b* values between 20.46 and 40.67; these polymers were much lighter in colour than those of the corresponding trimellitimide series. All polymers were readily soluble in a variety of organic solvents such as NMP, N,N‐dimethylacetamide, dimethyl sulfoxide, and even in the less polar m‐cresol and pyridine. Compared with those of corresponding ODPA–MDA polyimide, the solubilities of poly(amide–imide–imide)s IIIa–j were greatly improved. Polymers IIIa–j afforded tough, transparent, and flexible films, which had tensile strengths ranging from 82 to 105 MPa, elongations at break from 8 to 14%, and initial moduli from 2.0 to 2.2 GPa. The glass transition temperature of polymers were recorded at 255–288 °C. They had 10% weight loss at a temperature above 540 °C and left more than 60% residue even at 800 °C in nitrogen.© 2002 Society of Chemical Industry

Synthesis and characterization of soluble copoly(ether ketone)s containing double bonds

AbstractA series of copoly(ether ketone)s containing double bonds along the polymer chains were synthesized from the condensation polymerization of hydroquinone with 4,4′‐difluorobenzophenone and 4,5‐bis(4‐fluorobenzoyl)‐1‐methylcyclohexene in sulfolane containing anhydrous potassium carbonate. The presence of methylcyclohexene in the polymer chains resulted in an improvement in the solubility of poly(ether ketone)s in organic solvents such as chloroform, chlorobenzene, and sulfolane. As a result, the conditions for synthesizing these polymers were much milder than those for poly(ether ether ketone). The new copoly(ether ketone)s also showed good tensile properties and reasonable thermal stability. New polyethers containing pyrazine unites were obtained from the cyclization reaction of these copoly(ether ketone)s with hydrazine. The hydrazine cycloderivatives led to an increase in the glass‐transition temperatures and a decrease in solubility in organic solvents. © 2002 Government of Canada. Exclusive world‐wide publication rights in the article have been transferred to Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3449–3454, 2002

Synthesis and properties of new soluble poly(amide‐imide‐imide)s

AbstractA new‐type tetraimide‐dicarboxylic acid (I) was synthesized starting from the ring‐opening addition of p‐aminobenzoic acid (p‐ABA), 4,4'‐oxydiphthalic anhydride (ODPA), and 4,4'‐methylenedianiline (MDA) at a 2:2:1 molar ratio in N‐methyl‐2‐pyrrolidone (NMP), followed by cyclodehydration to the diacid I. A series of poly(amide‐imide‐imide)s (IIIa‐i) with inherent viscosities of 0.78–1.45 dL/g was prepared by triphenyl phosphite‐activated polycondensation from the tetraimide‐diacid I with various aromatic diamines (IIa‐i) in a medium consisting of NMP, pyridine, and calcium chloride. Most of the polymers were readily soluble in a variety of organic solvents such as NMP, N,N‐dimethyl acetamide, dimethyl sulfoxide, and even in less polar m‐cresol. Compared with those of the corresponding poly(amideimide)s IVa‐i, the solubilities of poly(amide‐imide‐imide)s IIIa‐i were greatly improved. Polymers IIIa‐h afforded tough, transparent, and flexible films, which had tensile strengths ranging from 87 to 107 MPa, elongations at break from 9% to 14%, and initial moduli from 2.0 to 2.4 GPa. The glass transition temperatures of polymers were recorded at 270°C–309°C. They had 10% weight loss at temperatures in the range of 540°C–570°C and left more than 52% residue even at 800°C in nitrogen.

New soluble poly(amide–imide–imide)s based on tetraimide-dicarboxylic acid condensed from 4,4 ′-oxydiphthalic anhydride, 2,2-bis[4-(4-aminophenoxy)phenyl]sulfone, and p-aminobenzoic acid, and various aromatic diamines

A new-type tetraimide-dicarboxylic acid ( I ) was synthesized starting from the ring-opening addition of p-aminobenzoic acid, 4,4 ′-oxydiphthalic anhydride, and 2,2-bis[4-(4-aminophenoxy)phenyl]sulfone (BAPS) at a 2:2:1 molar ratio in N-methyl-2-pyrrolidone (NMP), followed by cyclodehydration to the diacid I . A series of poly(amide–imide–imide)s ( III a–i ) with inherent viscosities of 0.71–0.99 dl/g was prepared by triphenyl phosphite-activated polycondensation from the tetraimide-diacid I with various aromatic diamines ( II a–i ) in a medium consisting of NMP, pyridine, and calcium chloride. All of the polymers were readily soluble in a variety of organic solvents such as NMP, N, N-dimethyl acetamide, dimethyl sulfoxide, and even in less polar m-cresol. Compared with those of the corresponding poly(amide–imide)s IV a–i , the solubilities of poly(amide–imide–imide)s III a–i were greatly improved. Most of the polymers III afforded tough, transparent, and flexible films, which had a tensile strength ranging from 94 to 100 MPa, elongation at break from 7 to 9%, and initial tensile modulus from 2.0 to 2.3 GPa. The glass transition temperature of polymers was recorded at 265–291 °C. They had 10% weight loss at a temperature above 550 °C and left more than 50% residue even at 800 °C in nitrogen.

Synthesis and properties of new soluble poly(amide–imide–imide)s based on tetraimide-dicarboxylic acid condensed from ODPA, BAPP and p-ABA, and various aromatic diamines

A new-type of tetraimide-dicarboxylic acid ( I) was synthesized starting from ring-opening addition of p-aminobenzoic acid ( p-ABA), 4,4′-oxydiphthalic anhydride (ODPA) and 2,2-bis[4-(4-aminophenoxy)phenyl]propane (BAPP) at a 2:2:1 molar ratio in N-methyl-2-pyrrolidone (NMP), followed by cyclodehydration to the diacid I. A series of poly(amide–imide–imide)s ( III a–i) with inherent viscosities of 0.82–1.20 dl g −1 was prepared by triphenyl phosphite-activated polycondensation from the tetraimide-diacid ( I) with various aromatic diamines ( II a–i) in a medium consisting of NMP, pyridine, and calcium chloride. Most of the polymers were readily soluble in a variety of organic solvents such as NMP, N, N-dimethyl acetamide (DMAc), dimethyl sulfoxide (DMSO), and even in less polar m-cresol. In comparison with corresponding poly(amide–imide)s ( IV a–i), the solubilities of poly(amide–imide–imide)s ( III a–i) were largely improved. Most of the polymers ( III) afforded tough, transparent, and flexible films, which had tensile strengths ranging from 96 to 107 MPa, elongations at break from 9 to 16%, and initial moduli from 2.0 to 2.3 GPa. The glass transition temperatures of polymers recorded at 257–278 °C. They had 10% weight loss temperature above 540 °C and left more than 46% residue even at 800 °C in nitrogen.

Prediction of the Solubility of Chloroform in Acrylate Polymer Mixtures with Inclusion of the Hydrogen-bonding Effect

In this paper, the presence of hydrogen bonding in chloroform−acrylate polymer mixtures was demonstrated by observation of 1H and 13C NMR chemical shifts. Comparison of the NMR chemical shifts in polymer solutions with their low molecular weight analogues showed the effect of steric hindrance on hydrogen bonding. Using the data obtained by NMR analysis, this work correlates the proton chemical shift with the fraction of associated hydrogen in chloroform, which is related to the polymer steric hindrance effect on molecular association. A lattice-fluid hydrogen bonding and equation of state (LFHB-EOS) model enables correct prediction of chloroform solubility in poly(acrylate)s due to the inclusion of hydrogen bonding and its equation of state nature. This initial investigation is helpful for understanding intermolecular interaction for relatively weak hydrogen-bonded polymer solutions.

Development of a nonaqueous solvent system for poly(vinyl alcohol) and its characterization

Solubility of poly(vinyl alcohol) (PVA) in water prevents the preparation of various derivatives through homogeneous techniques as most of the derivatives thus formed are insoluble in aqueous medium. There are a number of solvents that can swell PVA under hot conditions but cannot dissolve PVA. In the present study, N,N-dimethyl acetamide (DMAc) has been identified as solvent in which PVA can be dissolved in the presence of an equimolar amount of lithium chloride (LiCl). 1H nuclear magnetic resonance (1H-NMR), 13C-NMR, infrared (IR), and X-ray diffraction (XRD) studies have been carried out to characterize the regenerated poly(vinyl alcohol) (RPVA). DMAc–LiCl is found to be a true solvent system for dissolution of PVA. An attempt has also been made to prepare poly(vinyl acetate) from this solution of PVA by a homogeneous technique. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 663–669, 1999

Gas permeability, diffusivity, and solubility of poly(4‐vinylpyridine) film

Gas permeability, diffusivity, and solubility of poly(4‐vinylpyridine) film