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Abstract  

The present report deals with some results on phase behavior, miscibility and phase separation for several polymer blends casting from solutions. These blends are grouped as the amorphous polymer blends, blends containing a crystalline polymer or two crystalline polymers. The blends of PMMA/PVAc were miscible and underwent phase separation at elevated temperature, exhibited LCST behavior. The benzoylated PPO has both UCST and LCST nature. For the systems composed of crystalline polymer poly(ethylene oxide) and amorphous polyurethane, of two crystalline polymers poly(-caprolactone) and poly[3,3,-bis-(chloromethyl) oxetane], appear a single T g, indicating these blends are miscible. The interaction parameter B's were determined to be –14 J cm–3, –15 J cm–3 respectively. Phase separation of phenolphthalein poly(ether ether sulfone)/PEO blends were discussed in terms of thermal properties, such as their melting and crystallization behavior.

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Introduction Thermal transitions and phase behavior in polymer blends can be temperature dependent, as revealed in common upper critical solution temperature (UCST) or lower critical solution temperature (LCST) phenomena. UCST

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, organic solvents, and ionic liquid. However, phase behavior of binary mixture in confined state has rarely been investigated. Czwartos et al. [ 15 ] have studied solid–liquid (s–l) phase diagram of C 6 H 5 Br–CCl 4 confined in CPGs with average pore

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Journal of Thermal Analysis and Calorimetry
Authors: Nadia Mayoufi, Didier Dalmazzone, Walter Fürst, Leila Elghoul, Adel Seguatni, Anthony Delahaye, and Laurence Fournaison

latent heat of phase change. In this study, this technique was used to investigate the CO 2 pressure effect on the phase behaviour and the enthalpy changes in the system CO 2 + TBMAC + H 2 O. In addition, IR spectrometry experiments were performed for

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[ 7 ]. Archaeal tetraether lipids are an excellent source for the formation of mixed liposomes with enhanced tightness against solute leakage [ 8 ]. In this study, we investigated the phase behaviours and permeabilities of mixed C 25,25 –DPPC liposomes

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stigmasterol (shown in Fig. 1 ) have been used to prepare liposomes. We have investigated the thermotropic phase behavior of stigmasterol/DPPC liposomes and constructed the binary phase diagram of this binary system employing differential scanning calorimetry

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Abstract  

The phase behaviour of the twin-tailed surfactant dioctadecyldimethylammonium bromide with water was studied by DSC, FT-IR, X-ray and polarizing microscope. The phase diagram of DODAB-water system is very similar to that of DODAC-water. The dihydrate is in equilibrium with isotropic solution below 55°C. Above this temperature there is a lamellar liquid crystalline region, in equilibrium with isotropic liquid and solid crystals of DODAB·2H2O, up to 69°C. From 69 to 86°C, the lamellar mesophase is in equilibrium with ‘waxy’ anhydrous DODAB. From 86 to 116°C and very high DODAB content, there is a very narrow region of existence of inverse hexagonal mesophase, in equilibrium via a narrow biphase region with lamellar mesophase. AtT > 116°C an isotropic liquid appears. There seems to exist two different lamellar mesophases, one of them between 10 and 40 wt.% DODAB and the other between 60 and about 97 wt.% DODAB, with a biphase zone between them.

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mechanism of high molecular weight n -paraffins in the presence of solvents and asphaltenes of different chemical nature where the liquid–solid phase behavior and crystallinity are studied by means of Differential Scanning Calorimetry (DSC) and FT

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the phase behavior of PSIA11/PBM4VP26, PSIA11/PBM4VP37, PSIA27/PBM4VP26, and PSIA27/PBM4VP37 blends in the 253–413 K temperature, to avoid the formation of anhydrides, and considering that free water was fully removed in this temperature range; bound

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Abstract  

The phase behaviour of carbon dioxide confined in VYCOR glass at pressures below that of the bulk triple point (0.51 MPa) has been investigated. The temperature at which freezing occurs appears to be pressure dependent below 0.3 MPa. As experiments are performed at successively lower pressures, the confined phase transitions gradually disappear, due to either partial pore filling, or the proximity of the confined triple point.

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