Solubility Parameter Of Poly Research Articles

Phase equilibrium and rheology of poly(1-trimethylsilyl-1-propyne) solutions

The phase equilibrium and rheological properties of poly(1-trimethylsilyl-1-propyne) solutions obtained with tantalum catalysts are studied. For three polymers with different molecular masses, phase diagrams are determined in a number of solvents. From these diagrams, the Hansen solubility parameters of poly(1-trimethylsilyl-1-propyne) are calculated by the method proposed in this work. Dilute solutions of poly(1-trimethylsilyl-1-propyne) behave as Newtonian liquids, whereas the viscosity of viscoelastic concentrated systems decreases as the shear rate grows. The molecular and rheological characteristics of studied poly(1-trimethylsilyl-1-propyne) samples are compared with the samples prepared with NbCl5 catalysts. Poly(1-trimethylsilyl-1-propyne) obtained with a catalytic system involving tantalum pentachloride is characterized by high intrinsic viscosity and solution viscosity compared to poly(1-trimethylsilyl-1-propyne) prepared with niobium catalyst. The difference in properties is due to the dissimilar ratios of cis and trans units in the samples.

Thermal Degradation Behavior of Methyl Methacrylate Derived Copolymer

A novel copolymer of 2-hydroxy-3-menthyloxy-1-(4-methoxyphenyl)-3-oxopropyl methacrylate (HMOPMA) and methyl methacrylate (MMA), [poly(HMOPMA-co-MMA)], was synthesized by free radical polymerization. The percentages of HMOPMA and MMA units obtained in the copolymer composition were 19% and 81%, respectively. The solubility parameter of poly(HMOPMA-co-MMA) was found to be 10.3 cal(1/2) cm(-3/2) by turbidimetric titration method. Thermal degradation mechanism and activation energies for initial decomposition process under non-isothermal conditions were determined by integral approximation methods from the thermogravimetric study. The decomposition activation energies of poly(HMOPMA-co-MMA) using Kissinger and Flyn-Wall-Ozawa methods were calculated as 119.99 kJ/mol and 125.34 kJ/mol, respectively. The study of kinetic equations showed that the reaction mechanism of decomposition process in the conversion range studied progressed with D1 mechanism, one-dimensional diffusion of deceleration type of solid state mechanism.

Polyphosphazene membrane for desulfurization: Selecting poly[bis(trifluoroethoxy) phosphazene] for pervaporative removal of thiophene

Concerning the standstill state of pervaporation desulfurization, development of new pervaporation desulfurization membranes is vital. The polymer selection can be based on solubility parameter theory. Using group contribution method, the solubility parameter of poly[bis(trifluoroethoxy) phosphazene] (PTFEP) was calculated. The differences in solubility parameters between thiophene and polymers including PTFEP were calculated and investigated for their potential application as pervaporation desulfurization membranes. PTFEP had the most similar solubility parameter to thiophene among the polymers calculated in this work. The results indicated superior possibility for its application in pervaporation desulfurization. PTFEP was thus synthesized and characterized by DSC, GPC, XPS, 1H-NMR and 31P-NMR. The PTFEP composite membrane was fabricated and utilized in pervaporation removal of thiophene. A pretty high sulfur enrichment factor of 15.69 was obtained which confirmed the results suggested by the solubility parameter theory. Compared with literatures, we positively believe that an increase in solubility parameter differences causes a decrease in sulfur enrichment factor. Meanwhile, the swelling behavior and morphology of the membrane, the effect of feed temperature, and the effect of feed sulfur concentration were also investigated.

Preparation of a Pyrazosulfuron-Ethyl Imprinted Polymer with Hydrophilic External Layers by Reversible Addition-Fragmentation Chain Transfer Precipitation and Grafting Polymerization

A new imprinted polymer with both functions of molecular recognition and macromolecule exclusion was synthesized for selective extraction of pyrazosulfuron-ethyl and removal of humic acids in environmental analysis. In the preparation, spherical pyrazosulfuron-ethyl imprinted polymers were synthesized by reversible addition–fragmentation chain transfer (RAFT) precipitation polymerization. The hydrophilic polymer layers were then grafted on the surface of the imprinted polymer microspheres using post-RAFT polymerization. The conditions that influence the selectivity, size, and uniformity of the imprinted microspheres were studied systematically. The computer simulation was employed to study the template-monomer interaction. The solubility parameters of poly(MAA-co-EDMA) and porogen were calculated to investigate the relationship between the particle size and the solubility parameter. The results indicated that the pyrazosulfuron-ethyl imprinted polymers have special affinity for the template and several structurally related sulfonylurea herbicides. The molecularly imprinted polymer (MIP) with external hydrophilic chains not only had function of template retention, but also better function of protein/humic acid exclusion. This research demonstrates that multifunctional imprinted material with a narrow size distribution can be prepared by the RAFT polymerization.

Determination of secondary transitions and thermodynamic interaction parameters of poly (ether imide) by inverse gas chromatography

The retention diagrams of poly(ether imide) for ethyl benzene, n-propyl benzene, isopropyl benzene, chloro benzene, n-butyl acetate, tert-butyl acetate, isoamyl acetate, n-nonane, n-decane, n-undecane, n-dodecane and n-tridecane were obtained by inverse gas chromatography technique. In this work, the slope changes on the diagram were assigned as secondary transitions. The secondary transition temperatures obtained by inverse gas chromatography technique are in good agreement with the ones obtained by thermally stimulated depolarization current in the literature. Specific retention volume, V g 0, the weight fraction activity coefficients of the solvents at infinite solution, Ω1∞, Flory-Huggins polymer-solvent interaction parameters,χ12∞, equation-of-state polymer-solvent interaction parameters,χ12*, effective exchange energy parameters, X eff were determined. Later, the partial molar heat of sorption, $\Delta\bar{H}_{1,sorp}$ and the partial molar heat of mixing, $\Delta\bar{H}_1^{\infty}$ were obtained. The solubility parameter of poly(ether imide), δ2 was determined as 10.7 (cal/cm3)1/2 by extrapolation of the δ2 values obtained by considering the free volume effects from studied temperature range to room temperature.

Solubility Parameters of Cross‐Linked Poly(N‐Vinyl‐2‐pyrrolidone‐co‐crotonic Acid) Copolymers Prepared by γ‐Ray‐Induced Polymerization Technique

Poly(N‐vinyl‐2‐pyrrolidone‐co‐crotonic acid) [P(VP/CrA)] copolymers were prepared by irradiating the ternary mixture of VP/CrA and cross‐linking agent ethylene glycol dimethacrylate (EGDMA) in water by γ‐rays at ambient temperature. The solubility parameters of these copolymers were determined by 20 solvents with various solubility parameters in swelling experiments. The solubility parameter of poly(N‐vinyl 2‐pyrrolidone (PVP)) homopolymer was determined to be 32.26 ± 0.09 (MPa)1/2. However, the solubility parameters of P(VP/CrA) networks did not change much with crotonic acid (CrA) content increase in the network.

Solubility parameters of poly(sulfonyldiphenylene phenylphosphonate) and its miscibility with poly(ethylene terephthalate)

AbstractThe solubility behaviors of poly(sulfonyldiphenylene phenylphosphonate) (PSPPP), a very efficient flame retardant for poly(ethylene terephthalate) (PET), in more than 50 solvents were examined. Its solubility parameters (δ) were determined by the intrinsic viscosity and turbidic titration methods. The two methods obtained consistent results, δ = 21.0–21.6 J1/2/cm3/2 and δ = 21.0 J1/2/cm3/2, and the three‐dimensional solubility parameters were δd = 18.9 J1/2/cm3/2, δp = 8.8 J1/2/cm3/2, and δh = 5.9 J1/2/cm3/2. The miscibility of PSPPP with PET was estimated by the calculation of the heats of mixing, which were related to the difference between the solubility parameters of PSPPP and PET. Fourier transform infrared was used to examine the interactions between PSPPP and PET macromolecules, which were the internal factors of polymer–polymer miscibility. The results showed that PSPPP and PET were miscible within a very wide composition range, especially with less than 15 wt % PSPPP, a composition of interest for the preparation of flame‐retardant PET. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2296–2301, 2003

Determination of Thermodynamic Properties of Poly(4-tert-Butylstyrene) by Inverse Gas Chromatography

Abstract Some thermodynamic quantities were obtained for the interactions of poly (4-tert-butylstyrene) with alcohols, ketones, acetates, aromatics and alkanes by the inverse gas chromatography method in the temperature range of 343-463 K. The specific retention volumes (Vg°), the adsorption enthalpy of probes (ΔH2), the partial molar free energy of sorption (ΔG1 S), the enthalpy of sorption (ΔH1 S), the entropy of sorption (ΔS1 S), the weight fraction activity coefficients of solute probes at infinite dilution (Ω1 ∞), and the Flory- Huggins thermodynamic interaction parameters (χ∞ 12) between polymer and solvents are given. The partial molar free energy (ΔG1 ∞, the partial molar heat of mixing (ΔH1 ∞ at infinite dilution and the solubility parameters of the polymer (δ2) were calculated. The solubility parameter of poly (4-tert-butyl- styrene) was determined from either the slope or intercept as 7.25 (cal/cm3)0,5 and 7.00 (cal/cm3)0,5 at 180°C, respectively.

Pentaerythritol triacrylate-homopolymer and its copolymers with butyl acrylate

The swelling and porosity change of the pentaerythritol triacrylate (PENTA) homopolymer and PENTA-butyl acrylate (BA) copolymers were investigated as a function of PENTA content (80, 60, 40 and 20 wt%). Polymers were synthesized by the suspension polymerization method using cyclohexanol and 2-ethylhexanol as inert diluents. The solubility parameter of poly(PENTA) ( 18.2 MPa 1 2 ) was estimated by swelling in the heptane and tetraline mixture. From the swelling of copolymers in the solvents toluene, THF, benzene and dioxane, one may conclude that the swelling of copolymers is not only a function of the solubility parameter of the solvent. The presence of hydroxyl groups in PENTA results in the highest sorption of dioxane. The porosity of copolymers in the swollen state is similar in all solvents. The porosity in the swollen state was characterized by inverse size exclusion chromatography (ISEC) using THF (polystyrene standards) and water (dextrane standards). Swelling in good solvents proceeds with an enlargement of the bead volume, hence the pore volume after swelling in THF is greater than in water in which the influence of hydroxyl groups leads to swelling of triacrylate segments at the cost of the pore volume. Copolymers synthesized with the higher diluents:monomer ratio are hydrogels with the ability to change their porosity, pore diameter and volume of beads. During drying, their pores collapse.

Estimation of Solubility Parameters of Poly(Methyl Methacrylate) and Derivatives by Inverse Gas Chromatography

Abstract Flory – Huggins polymer–solute interaction (χ1 2) parameters have been determined by inverse gas chromatography (i.g.c.) at 453–463 K for alkanes, alcohol, acetates, ketones and O – Xylene in PMMA, PEMA, PIBMA and Pt-BMA to estimate the polymer solubility parameters (δ2) Partial molar free energies of mixing (ΔG1 ∞) and weight fraction activity coefficients of solute probes at infinite dilution (Ω1 ∞) were calculated at temperature range 453–463 K.

Physico-chemical characterization of a polymeric injectable implant delivery system

Physico-chemical properties of an injectable polymeric implant system were evaluated and utilized to predict and understand the in vivo release of a model drug. The injectable implant system is based on the principle that a water insoluble polymer, dissolved in a biocompatible solvent, will precipitate upon contact with water. The solubility parameter of poly( dl-lactide) and dl-lactide-co-glycolide copolymers were experimentally determined by evaluating the solubility of these polymers in hydrogen bonding solvents having solubility parameters ranging from 8.9 to 14.8 (cal/cm 3) 1 2 . The appropriate Flory-Huggins interaction parameters were then calculated at 25 and 37°C. Analysis of ternary phase diagrams indicated that the quantity of water needed to initiate precipitation, as well as the precipitation threshold, increased with increasing temperature in agreement with theoretical calculations. Rats were subcutaneously administered formulations comprised of polymer concentrations above and below the precipitation threshold, i.e., 40% w/w polymer. Formulations with polymer concentrations below the precipitation threshold exhibited approximately twice the initial release compared to formulations having a polymer content above the precipitation threshold. A key factor affecting the initial release of a model drug from formulations was the polymer content of the formulation with respect to the precipitation threshold. The reported method of analysis may be utilized to screen polymers and biocompatible solvents for use in these injectable implant systems.

Study by gas-liquid chromatography of the thermodynamics of the interaction of poly(vinyl acetate) with various solvents

The solubility parameter of poly(vinyl acetate) at various temperatures has been obtained by using the method developed by DiPaola-Baranyi and Guillet, Marcomolecules 11, 228 (1978). The solubility parameter of polymer at 25°C was found to be 10.1 ( cal/cm 3) 1 2 by linear extrapolation from higher temperatures (70–140°C). The interaction parameter χ of polymer in various solvents, at temperatures below the melting point T m , has been determined by means of the solubility parameters of the polymer and solvents at this temperature, deduced from their values obtained chromatographically at higher temperatures. The value of the interaction parameter so obtained is in good agreement not only with values calculated by other techniques but also is independent of the temperature range used for the chromatographic measurements. Moreover, using the equation-of-state theory formulation, we have determined the values of the interaction parameters χ ∗ for various systems poly(vinyl acetate)/probes and from it the contact interaction energy, X 12, in the temperature range 70–140°C.

Solubility parameters in polyoxetanes: Poly(oxetane), poly(3,3‐dimethyl oxetane), and poly(3,3‐diethyloxetane)

AbstractThe solubility parameter of poly(oxetane), poly(3,3‐dimethyloxetane) and poly(3,3‐diethyl oxetane) has been estimated by measuring solution viscosities. Values of δ = 9.4, 7.9, and 7.9 cal1/2·cm−3/2 for each polymer were obtained and compared with those calculated from empirical methods. The 3‐dimensional solubility parameter approach has been also applied in order to get additional information on the effect of structural modifications on the main chain in the solubility behavior.

Determination of the solubility parameter of poly(ethylene oxide) at 25°C by gas-liquid chromatography

The solubility parameter of poly(ethylene oxide) at 25°C has been determined using the method developed by DiPaola-Baranyi and Guillet, by the extrapolation of the values of the interaction parameter χ, at high temperatures, ranging from 70°–90°, 90°–110° and 110°–130°C down to 25°C. The values of the solubility parameter obtained, depending on the temperature ranges employed, are 9.8, 9.9 and 10.1, respectively.

Cohesive energy densities of polyethers: Poly(hexamethylene oxide)

The solubility parameter of poly(hexamethylene oxide) has been estimated by measuring solution viscosities and by turbidimetric titrations in a series of solvents. From both experimental methods, a value of δ p = 33.9 J 1 2 cm −3 2 ( 8.1 cal 1 2 cm −3 2 ) was obtained, whence the cohesive energy density is 274.5 J cm −3 (65.6 cal cm −3). These experimental values are compared with those calculated by empirical methods.