Showing papers on "Miscibility published in 1979"
115 citations
TL;DR: In this article, the melting point of poly(butylene terephthalate) (PBT) and the polyhydroxyether of bisphenol A (phenoxy) was investigated.
Abstract: Melt blends of poly(butylene terephthalate) (PBT) and the polyhydroxyether of bisphenol A (phenoxy) exhibit excellent transparency above the melting point of PBT as well as for the quenched molded specimens. Dynamic mechanical and calorimetric characterization revealed single and sharp glass transitions intermediate between those for the individual constituents. Increasing phenoxy content in the blends depressed the crystallization rate of PBT due to dilution and viscosity (Tg increase) effects. The apparent miscibility is believed due to the potential specific interactions between phenoxy pendant hydroxyl (proton donor) and the ester carbonyl of PBT (proton acceptor). Heat of fusion results surprisingly show an increase in the degree of PBT crystallinity as the phenoxy content of the blend is increased. No explanation is offered at this point for this unexpected behavior.
109 citations
TL;DR: In this article, the location of the diblock copolymer in 1-4-polybutadiene and cis-1-4 polyisoprene copolymers was found to depend upon the relative lengths of the block segments and the coordinates of the binary or ternary mixture on the appropriate triangular composition diagram.
Abstract: : The miscibility of homogeneous diblock copolymers of 1-4-polybutadiene and cis-1-4 polyisoprene with either or both of the corresponding linear homopolymers was found to depend upon the relative lengths of the block segments and upon the coordinates of the binary or ternary mixture on the appropriate triangular composition diagram. Evidence from a variety of experiments was used to draw overall conclusions regarding the location of the diblock in these blends and its influence on physical properties.
50 citations
TL;DR: In this article, solid solubilities progressively decrease in the systems CaS-MnS, CaSe-mnSe, and CaTe-mTe, and the liquidus minimum is reached at 1150° to 1500°C.
Abstract: Solid solubilities progressively decrease in the systems CaS-MnS, CaSe-MnSe, and CaTe-MnTe. In CaS-MnS, full solid miscibility extends from 1150° to 1500°C, the liquidus minimum. With CaSe-MnSe, this range is 1070° to 1340°C. The solid miscibility gap between CaTe and cubic MnTe intercepts the liquidus as a eutectic at 1050°C. The solid solutions follow Vegard's law closely.
44 citations
01 Jan 1979
35 citations
TL;DR: In this article, the total miscibility method is applied to study the recently discovered mesophases of disc-like molecules, benzene-hexa-n-alkanoates.
Abstract: The total miscibility method is applied to study the recently discovered mesophases of disc-like molecules, benzene-hexa-n-alkanoates. These compounds do not form continuous solid solutions, but are totally miscible in the liquid and mesomorphic states. The virtual mesophase-isotropic transition temperature for the hexanoate compound derived from the miscibility diagram is in excellent accord with that obtained from the previously reported pressure-temperature phase diagram. With simplifying assumptions, it is possible to predict with acceptable reliability the isobaric binary phase diagrams of any two members of the series. The real and virtual mesophase-liquid transition temperatures are linear functions of the molecular weight. On the other hand, a plot of the crystal-liquid transition temperatures versus the molecular weight exhibits a minimum. Total miscibility in the mesomorphic state is not observed for two members of different discogenic series, but the existence of different mesophase types is not proved. Lyotropic mesomorphism for a disc-like mesophase is established.
29 citations
01 Jan 1979
21 citations
TL;DR: The mutual solubility of mixed micelles of fluorocarbon and hydrocarbon surfactants was determined by surface tension measurements, as convincing evidence for the partial miscibility postulated by Mukerjee and Yang as mentioned in this paper.
Abstract: The mutual solubility in mixed micelles of fluorocarbon and hydrocarbon surfactants was determined by surface tension measurements, as convincing evidence for the partial miscibility postulated by Mukerjee and Yang.
19 citations
TL;DR: The effect of polyester structure on miscibility with polycarbonate is interpreted by and correlated with heats of mixing obtained by direct calorimetry of low molecular weight liquid analogs of the polymers as mentioned in this paper.
Abstract: Polycarbonate blends with the linear aliphatic polyesters poly(ethylene succinate) (PES), poly(ethylene adipate) (PEA), poly(1,4-butylene adipate) (PBA), and poly(hexamethylene sebacate) (PHS) were prepared by solution casting. Blends containing PES, PEA, and PBA exhibited a single Tg by DSC and thus form a single, miscible amorphous phase with polycarbonate. However, blends containing PHS exhibited only partial miscibility. Crystallinity of the polyesters was reduced by mixing with polycarbonate; however, plasticization by the polyesters induced crystallization of the polycarbonate. Miscibility in these systems is the result of an exothermic heat of mixing stemming from an interaction of the carbonyl dipole of the ester group with the aromatic carbonate. The effect of polyester structure on miscibility with polycarbonate is interpreted by and correlated with heats of mixing obtained by direct calorimetry of low molecular weight liquid analogs of the polymers.
18 citations
Patent•
28 Dec 1979TL;DR: In this paper, a hydrophilic, water-containing regenerated cellulose membrane is sequentially permeated under differential pressure with solvents of decreasing polarity so as initially to displace water in the membrane with a first solvent, and the or each other solvent in the sequence displacing the previous solvent.
Abstract: A hydrophilic, water-containing regenerated cellulose membrane is sequentially permeated under differential pressure with solvents of decreasing polarity so as initially to displace water in the membrane with a first solvent, and the or each other solvent in the sequence displacing the previous solvent. Each solvent has bulk liquid-liquid miscibility with the adjacent soivent(s) in the sequence, and the final solvents of the sequence exhibits bulk liquid-liquid miscibility with a material ultimately desired to be selectively permeated through the membrane. The first solvent is a lower (C,-C 4 ) alcohol or acetone. The resulting membrane is particularly suitable for at least partially separating, by permeation, a solvent used in dewaxing a waxy hydrocarbon oil from a solution of the oil and solvent.
TL;DR: In this paper, a systematic investigation of the miscibility between 1.c. phases in binary systems by the Halle Liquid Crystal Group was extended to the following homologous series, including the phase types N, A, C, F, B and G.
Abstract: The systematic investigation of the miscibility between 1.c. phases in binary systems by the Halle Liquid Crystal Group was extended to the following homologous series The different variants of polymorphism in these series including the phase types N, A, C, F, B and G are discussed with respect to structural informations especially on the ordered smectic phases of the types F, B and G. A new phase type H has to be established. These phases are low temperature modifications in the sequence FGH of the tilted ordered smectic phases.
TL;DR: In this paper, it was shown that poly(2,2-dimethyl-1,3-propylene succinate) is partially miscible with polycarbonate because the shielding is not so great since the methyl groups are further removed from the ester group.
Abstract: Polycarbonate blends with poly(pivalolactone) were found to be completely immiscible based on the glass transitional behavior observed by thermal analysis. Crystallinity of the poly(pivalolactone) was unaffected by blending with polycarbonate. The heat of mixing of low molecular weight analogs of this system, ethyl pivalate and diphenyl carbonate, were found to be endothermic, in contrast to exothermic mixing observed for similar linear esters. Methyl branching adjacent to the ester carbonyl is believed to shield the specific interaction of this unit with the aromatic carbonate structure which leads to exothermic mixing and miscibility of similar unbranched esters with polycarbonate. Blends of poly(2,2-dimethyl-1,3-propylene succinate) were found to be partially miscible with polycarbonate because the shielding is not so great since the methyl groups are further removed from the ester group.
TL;DR: In this article, the regeneration of 2% concentration solutions in dimethylformamide-NO2 solvent is used to produce transparent cellulose-polyacrylonitrile (PAN) blends.
Abstract: Cellulose-polyacrylonitrile (PAN) blends have been prepared by the regeneration of 2% concentration solutions in dimethylformamide–NO2 solvent. The blends are transparent when containing between 0 and 50% by weight of PAN. Dynamic mechanical measurements indicate a shift in glass transition temperature Tg of PAN for the blends, suggesting partial miscibility between cellulose and PAN. Experimental density values larger than those predicted theoretically are also in agreement with this conclusion.
TL;DR: In this paper, solid-liquid and liquid-liquid equilibria in the reciprocal ternary system K, Li/Br, F were fully measured and the projection of the miscibility gap occupied 20.8% of the composition square; the upper critical point of the gap is along the stable diagonal at 953°C and xLIF = 0.70.
Abstract: Solid-liquid and liquid-liquid equilibria in the reciprocal ternary system K, Li/Br, F were fully measured. The projection of the miscibility gap occupies 20.8% of the composition square; the upper critical point of the gap is along the stable diagonal at 953°C and xLIF = 0.70. Attempts to predict the liquid-liquid equilibria by means of the conformal ionic solution theory using temperature independent interaction parameters lead to an incorrect symmetry of the gap. The symmetry can be improved if the temperature dependence of the interaction parameters of the binary mixtures is taken into account.
TL;DR: In this paper, an additional term for taking into account the acid-base interaction is added to the expression for the hydrogen-bonding solubility parameter of the liquid mixture; the dispersion forces and polar interactions are assumed to be undisturbed by the occurrence of the acidbase interaction.
Abstract: A mixture of two organic liquids, each of which is a solvent for a given polymer, may become a nonsolvent mixture, if there is strong acid-base interaction between the two solvents. Experimental results of such cases are presented for five polymers. These results are then correlated with the proposed modified form of the two-dimensional approach. In the modification, an additional term for taking into account the acid-base interaction is added to the expression for the hydrogen-bonding solubility parameter of the liquid mixture; the dispersion forces and polar interactions are assumed to be undisturbed by the occurrence of the acid-base interaction.
01 Jul 1979
TL;DR: In this paper, the phase boundary curves for the pseudo three-component systems (constant sulfonate/water ratios, 2.5 moles sulfonates per kg water) were determined for four component systems containing sodium alkylbenzenesulfonates, toluene, n-butanol, and water.
Abstract: Miscibility relationships in four-component systems containing sodium alkylbenzenesulfonates, toluene, n-butanol, and water were studied at 25°C in the hope of clarifying the complex systems used in the “micellar flood” enhanced oil recovery process. Phase boundary curves for the pseudo three-component systems (constant sulfonate/water ratios, 2.5 moles sulfonate per kg water) were determined. The sulfonates included those of benzene, toluene, xylene, ethylbenzene, isopropylbenzene, mesitylene, cymene, methyl-t-butylbenzene, and diisopropylbenzene, in all of which the alkyl substituents are smaller than in the usual surfactants. The phase boundary curves have similar and fairly symmetrical shapes. The amount of n-butanol (cosolvent) required to produce miscibility decreases with increasing number of alkyl carbons on the benzene ring of the sulfonates and seems relatively independent of the isomeric structure. The sodium salt of diisopropylbenzenesulfonate gives the lowest phase boundary curve (least n-butanol required for miscibility) among the nine sulfonates studied.
Journal Article•
TL;DR: In this paper, the authors compared the results of short alkyl-side-chain sodium benzenecarboxylates, toluene, and water without (three-component systems) or with (four-component) 1-butanol.
Abstract: Miscibility relationships in systems containing short alkyl-side-chain sodium benzenecarboxylats, toluene, and water without (three-component systems) or with (four-component systems) 1-butanol were studied at 55 and 25/sup 0/C, respectively. The results are compared with corresponding sulfonates. The benzenecarboxylates included those of benzene, 2,4-dimethylbenzene, 2,4,6-trimethylbenzene, and tert-butylbenzene. The solubility of toluene in aqueous solutions of the carboxylates increases with the number of alkyl carbons N/sub AC/ attached to the benzene ring and generally with carboxylate concentration (up to ca. 3 mole/kg of H/sub 2/O); it is somewhat higher in the carboxylate solutions than in the corresponding sulfonate solutions. Four-component systems were treated as pseudoternary systems by maintaining a constant carboxylate to water ratio (2 mole/kg of water). Boundaries between one and two phases are fairly symmetrical. The amount of 1-butanol (cosolvent) required to produce miscibility decreases with increasing number of alkyl carbons on the carboxylate. These systems required somewhat less 1-butanol to produce miscibility than the corresponding sulfonate systems. 4 figures, 3 tables.
TL;DR: In this paper, a lower critical temperature for miscibility, by a decrease in enthalpy and by a decreasing in specific volume, was characterized for polyethers of different functionality with water, and the concentration position of the maximum exothermal effect was not symmetrical.
Abstract: Mixtures of polyethers of different functionality with water are characterized by a lower critical temperature for miscibility, by a decrease in enthalpy and by a decrease in specific volume The concentration position of the maximum exothermal effect is not symmetrical As the degree of branching of the polyether is decreased, the amount of water associated with one polymeric chain and the contraction of the mixture decrease The results are interpreted on the basis of ideas concerning the microheterogeneity of solutions in the region of moderate concentrations of water
TL;DR: Vollstandige experimentelle analyse der festflussig- und flussigflussigen-Gleichgewichte uber den gesamten Zusammensetzungs-and Temp.-bereich as discussed by the authors.
Abstract: Vollstandige experimentelle Analyse der fest-flussig- und flussig-flussig-Gleichgewichte uber den gesamten Zusammensetzungs- und Temp.-bereich.
TL;DR: In this article, the enthalpy of fusion of the ester is given, and a discussion is carried out on the factors affecting the liquid-liquid equilibria studied to date.
Abstract: The liquid-liquid and liquid-solid equilibria of the binary systems composed of methyl nonadecanoate and some aliphatic acids or stearic alcohol or diphenyl are presented; the enthalpy of fusion of the ester is given, and a discussion is carried out on the factors affecting the liquid-liquid equilibria studied to date.