Miscibility

About: Miscibility is a research topic. Over the lifetime, 5521 publications have been published within this topic receiving 133547 citations. The topic is also known as: miscible.

Photochemical transformation in poly(acrylic acid)/poly(ethylene oxide) complexes

Abstract: The poly(acrylic acid)/poly(ethylene oxide) (PAA/PEO) complexes with different stoichiometric ratio were obtained from aqueous solutions. The chemical structure of these blends in solid state and the interactions between components has been studied using mainly FT-IR spectroscopy. The miscibility of components was proved also by differential scanning calorimetry (DSC). The films of both pure polymers and their blends at different compositions were UV-irradiated ( λ = 254 nm) in air atmosphere. The course of photochemical transformations has been monitored by absorption spectroscopy (FT-IR, UV–vis), DSC, X-ray diffraction and thermogravimetry, which was also applied for estimation of the thermal properties of samples studied. It was found that photooxidative degradation is less efficient in PAA/PEO complexes than that in PAA and PEO exposed separately. The most photostable was PAA/PEO (50/50) blend. PAA disturbs crystallization PEO in the blends but changes in crystallinity degree of PEO/PAA during UV-radiation were negligible. Thermal stability of PAA/PEO complexes is lower comparing to pure components but UV-irradiation does not cause significant changes in thermal resistance of blends studied.

Phase behavior of poly(ethylene−1-butene) in subcritical and supercritical propane : ethyl branches reduce segment energy and enhance miscibility

Abstract: On the basis of experimental batch-cell data, increasing short-chain branch density is found to reduce the cloud-point pressure of poly(ethylene-1-butene) solutions in propane, by as much as a factor of 3. This trend is captured by a SAFT approximation via an effective. segment energy that depends on the branch density. Increasing branch density is found to decrease the effective segment energy and, hence, to make it closer to that of propane, which is consistent with the enhanced miscibility of branchy poly(ethylene-1-butenes) in propane

Thermal and Structural Analyses of PMMA/TiO2 Nanoparticles Composites

Abstract: In the present work, composites of poly (methyl methacrylate)/titanium oxide nanoparticles (100/0, 97.5/2.5, 95/5, 92.5/7.5, 90/10 and 0/100 wt/wt%)were prepared to be used as bioequivalent materials according to their importance broad practical and medical applications. Thermal properties as well as X-ray diffraction analyses were employed to characterize the structure properties of such composite. The obtained results showed variations in the glass transition temperature (Tg), the melting temperature (Tm), shape and area of thermal peaks which were attributed to the different degrees of crystallinity and the existence of interactions between PMMA and TiO2 nanoparticle molecules. The XRD patterns showed sharpening of peaks at different concentrations of nano-TiO2 powder with PMMA. This indicated changes in the crystallinity/amorphosity ratio, and also suggested that the miscibility between the amorphous components of homo- polymers PMMA and nano-TiO2 powder is possible.The results showed that nano-TiO2 powder mix with PMMA can improve the thermal stability of the homo-polymer under investigation, lead- ing to interesting technological applications.

Miscibility determination of a lower critical solution temperature polymer blend by rheology

Abstract: Rheology on a miscible blend of deuterated polystyrene (PSD) and poly(vinyl methyl ether) (PVME) is reported in the temperature range of Tg (glass-transition temperature) + 45 K to Tg + 155 K, exte...