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Melt Intercalation (melt + intercalation)
Terms modified by Melt Intercalation Selected AbstractsStructure and Properties of PHA/Clay Nano-Biocomposites Prepared by Melt IntercalationMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 14 2008Perrine Bordes Abstract PHA-based nano-biocomposites have been prepared by melt intercalation. Two main PHAs, poly(hydroxybutyrate) and poly(hydroxybutyrate -co- hydroxyvalerate) have been studied. Structural characterizations were conducted by advanced techniques like SAXS and TEM. A recent method has determined the degree of clay intercalation and dispersion using solid-state NMR. Well intercalated small tactoids (3,10 layers) homogeneously dispersed into the polymer are obtained when good PHA,clay affinity exists, i.e., with organo-modified MMT. In the case of non-modified MMT, microcomposites are evidenced. Crystallization, mechanical, and thermal properties have been correlated to the materials structures. [source] Preparation of LLDPE/MgAl-LDH Exfoliation Nanocomposites with Enhanced Thermal Properties by Melt IntercalationCHINESE JOURNAL OF CHEMISTRY, Issue 10 2006Long-Chao Du Abstract The interlayer surface of MgAl layered double hydroxide (MgAl-LDH) was modified by exchanging about half of the interlayer nitrate anions by dodecyl sulfate anions (DS) to get MgAl(H-DS) LDH, and then the MgAl(H-DS) was melt intercalated by LLDPE to get the LLDPE/MgAl-LDH exfoliation nanocomposites. The samples were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), ion chromatography, transmission electron microscopy (TEM), and thermogravimetry analysis (TGA). The nanoscale dispersion of MgAl-LDH layers in the LLDPE matrix was verified by the disappearance of (00l) XRD reflection of the modified MgAl-LDH and by the TEM observation. The TGA profiles of LLDPE/MgAl-LDH nanocomposites show a faster charring process between 210 and 370 °C and a higher thermal stability above 370 °C than LLDPE. The decomposition temperature of the nanocomposites with 10 wt% MgAl(H-DS) can be 42 °C higher than that of LLDPE at 40% weight loss. [source] Biodegradation of poly(butylene adipate- co -butylene terephthalate)/layered-silicate nanocompositesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 2 2007Yoshihiro Someya Abstract The biodegradability of poly(butylene adipate- co -butylene terephthalate) (PBAT) and PBAT/starch composites with layered silicates prepared by melt intercalation was evaluated with aerobic biodegradability tests in soil and in an aqueous medium containing activated sludge. Nonmodified montmorillonite (MMT) and octadecylamine-modified montmorillonite (ODA-M), known to give a microcomposite and an intercalated nanocomposite for PBAT, respectively, were used as layered silicates. After they were buried in the soil for 8 months, the PBAT/MMT microcomposite exhibited a higher weight loss than the control PBAT, whereas the PBAT/ODA-M nanocomposite showed a lower weight loss instead. Also, the biodegradability test in the aqueous medium, by determining the biochemical oxygen demand, showed that the addition of MMT and/or starch to PBAT promoted biodegradation, whereas the addition of ODA-M did not. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 [source] Structure and Properties of PHA/Clay Nano-Biocomposites Prepared by Melt IntercalationMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 14 2008Perrine Bordes Abstract PHA-based nano-biocomposites have been prepared by melt intercalation. Two main PHAs, poly(hydroxybutyrate) and poly(hydroxybutyrate -co- hydroxyvalerate) have been studied. Structural characterizations were conducted by advanced techniques like SAXS and TEM. A recent method has determined the degree of clay intercalation and dispersion using solid-state NMR. Well intercalated small tactoids (3,10 layers) homogeneously dispersed into the polymer are obtained when good PHA,clay affinity exists, i.e., with organo-modified MMT. In the case of non-modified MMT, microcomposites are evidenced. Crystallization, mechanical, and thermal properties have been correlated to the materials structures. [source] Polystyrene,organoclay nanocomposites prepared by melt intercalation, in situ, and masterbatch methodsPOLYMER COMPOSITES, Issue 3 2006Ulku Yilmazer In this study, polystyrene (PS)/montmorillonite nanocomposites were prepared by melt intercalation, in situ polymerization, and masterbatch methods. In the masterbatch method, as the first step, a high clay content composite of PS,organoclay (masterbatch) was prepared by in situ polymerization, and then the prepared masterbatch was diluted to desired compositions with commercial PS in a twin-screw extruder. The structure and mechanical properties of the nanocomposites were examined. X-ray diffraction (XRD) analysis showed that the d -spacing of the in situ formed nanocomposites increased from 32.9 Å for the organoclay powder to 36.3 and 36.8 Å respectively in nanocomposites containing 0.73 and 1.6 wt% organoclay, indicating intercalation. However, the d -spacing of the other prepared materials remained nearly unchanged when compared with pure organoclay powder. Thus, at these low clay contents, in situ formed nanocomposites showed the best improvement in mechanical properties including tensile, impact strength, and Young's modulus. In situ polymerization method did not prove to be efficient at high clay loadings in terms of intercalation and mechanical properties. At high clay loadings, the effects of the three methods in promoting mechanical properties were not significantly different from each other. POLYM. COMPOS., 27:249,255, 2006. © 2006 Society of Plastics Engineers [source] Thermodynamic characterization of hybrid polymer blend systemsPOLYMER ENGINEERING & SCIENCE, Issue 6 2009Amos Ophir A thermodynamic model was used to predict the morphology of hybrid multicomponent polymer blend systems. Two systems were studied, both including two noncompatible polymers, a third compatibilizer polymer and layered, organo-treated clays. The polar and nonpolar contributions of the surface energies of the components of the systems were calculated using measurements of the contact angles. The morphology of the multicomponent systems and the relative position of the organo-clays within them, were predicted by calculating the interaction energies between the different components of the system and evaluating these values according to the Vaia and Giannelis thermodynamic model for polymer melt intercalation in organically modified layered silicates. The experimental results show good correlation with the prediction that the organo-clays will have higher affinity to the compatibilizer polymer component situated at the interface between the two noncompatible blend components. In addition, the presence of the organo-clays in this interface was found to have a significant additional compatibilizing effect between the two polymer phases. The results presented in this work support the idea that hybrid formation via polymer melt intercalation depends mostly on energetic factors that can be determined from surface energies of polymers and organo-modified layered silicates, also in the case of multiphase polymer system. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers [source] A short review on rubber/clay nanocomposites with emphasis on mechanical propertiesPOLYMER ENGINEERING & SCIENCE, Issue 11 2007R. Sengupta The invention of Nylon-6/clay nanocomposites by the Toyota Research Group of Japan heralded a new chapter in the field of polymer composites. This article highlights the work done in the field of rubber/clay nanocomposites. The preparations of rubber/clay nanocomposites by solution blending, latex compounding, and melt intercalation are covered and a thorough discussion of the mechanical properties of the various rubber/clay nanocomposite systems is presented. Other properties such as barrier, dynamic mechanical behavior, and thermal properties are also discussed. Finally, the future trends in the rubber/clay nanocomposites are mentioned. POLYM. ENG. SCI., 47:1956,1974, 2007. © 2007 Society of Plastics Engineers [source] Water uptake behavior of layered silicate/starch,polycaprolactone blend nanocompositesPOLYMER INTERNATIONAL, Issue 2 2008C Javier Pérez Abstract The water uptake behavior of biodegradable layered silicate/starch,polycaprolactone blend nanocomposites was evaluated. Three different commercial layered silicates (Cloisite Na+, Cloisite 30B and Cloisite 10A) were used as reinforcement nanofillers. Tests were carried out in two different environments: 60 and 90% relative humidity using glycerol solutions. The clay/starch,polycaprolactone blend nanocomposites were obtained by melt intercalation and characterized by gravimetric measurements and tensile tests. The intercalated structure (determined by wide-angle X-ray diffraction) showed a decrease in water absorption as a function of clay content probably due to the decrease of the mean free path of water molecules. The diffusion coefficient decreased with clay incorporation but a further increase in the clay content did not show an important effect on this parameter. Elongation at break increased with exposure showing matrix plasticization. Mechanical properties of the nanocomposites deteriorated after exposure whereas they remained almost constant in the case of the neat matrix. Copyright © 2007 Society of Chemical Industry [source] | ||||||||||