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Abstract  

Fish oil which is characterised by important amounts of poly-unsaturated ω-3 fatty acids attach increasing importance within functional foods. Recently attention is directed on physical methods that allow fast and relatively easy the identification and discrimination of oils. DSC measurements yield in information on thermal effects, characterised by changes in enthalpy and their temperature range such as melting and crystallisation. The aim of the investigation presented here was to take DSC curves in the temperature range +20 to −40°C on several fish oils and fish oil capsules to visualise the crystallisation and melting behaviour and to compare transition temperatures and enthalpies.

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Abstract  

Composites made from an isotactic polypropylene matrix and wood (pine or beech) have been prepared and tested. To improve adhesion between components, the wood modification was performed by esterification with maleic, propionic, crotonic, succinic and phthalic anhydrides. The surface of wood fillers was also modified by chemical treatment with NaOH as well as by extraction process. Non-isothermal crystallisation of polypropylene in wood composites is studied by DSC, and the basic parameters of crystallisation are determined. We discovered that the composites containing chemical treated wood fillers showed the tendency reduction the nucleation efficiency of polypropylene. The ability of wood filler to induce nucleation in polypropylene matrix is dependent on the kind of chemical modification of surface wood

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Abstract  

Temperature modulated dynamic mechanical analysis (TMDMA) was performed in the same way as temperature modulated DSC (TMDSC) measurements. As in TMDSC TMDMA allows the investigation of reversible and non-reversible phenomena during crystallisation of polymers. The advantage of TMDMA compared to TMDSC is the high sensitivity for small and slow changes in crystallinity, e.g. during re-crystallisation. The combination of TMDMA and TMDSC yields new information about local processes at the surface of polymer crystallites. It is shown that during and after isothermal crystallisation the surface of the individual crystallites is in equilibrium with the surrounding melt.

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the basis of the crystallization curves, by designation the crystallization enthalpy. Crystallisation enthalpy was determined from the area under the crystallisation curve. On account of curves crystal conversion versus time, the half-time of

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Crystallisation behaviour of palm oil nanoemulsions carrying vitamin E

DSC and synchrotron X-ray scattering studies

Journal of Thermal Analysis and Calorimetry
Authors: Rizwan Shukat, Claudie Bourgaux, and Perla Relkin

. Previous studies on simple and complex oil-in-water emulsions [ 14 – 22 ] indicated that their structural properties are affected by several parameters including not only the lipid droplet composition and their related crystallisation and polymorphic

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Abstract  

The crystallisation properties of a mixture of triacylglycerols (TG), cocoa butter (CB) 75%/miglyol 25%, were investigated on cooling at 0.5 °C/min using differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The influence of (i) the dispersion of TG within nanoparticles stabilised by proteins, and of (ii) the presence of polar lipids were characterised. In bulk, crystallisation of TG successively occurred with a α 2L (49.3 Å) structure, then the formation of longitudinal stackings of 44.5 and 34.5 Å of β′ form was interpreted as co-crystallisation of TG from CB and miglyol. The dispersion of TG in nanoparticles of about 400 nm induced a higher supercooling and changed their crystallisation properties. The formation of α 49.2 Å and β′ 45 Å structures corresponded to the segregation of TG from CB in solid phases while TG from miglyol remained liquid. Phospholipids with saturated fatty acid chains affected the thermal properties of TG, which demonstrated their localisation at the surface of the nanoparticles. DSC and XRD revealed to be very sensitive and adapted methods to increase the knowledge about the mechanisms of crystallisation in emulsion.

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Abstract  

Hexanitrostilbene (HNS), is added to trinitrotoluene (TNT), in order to improve the grain structure of cast munitions. The formation and composition of the nucleant material has been investigated by thermal methods using mixtures of HNS and TNT, with composition in the range 0.5%, the normal casting level, to 50% w/w HNS to TNT. These were cycled between ambient and upper temperatures in the range 160 to 235°C. Endotherms in the DSC traces, due to nucleant decomposition, have been observed in situ without the need for separation and purification. DSC enthalpy measurements, before and after thermal decomposition, were used to determine the composition of separated nucleant. Nucleant regeneration after decomposition, was investigated by thermal methods. Nucleant could not be recrystallised from solvents. Results have been interpreted on the basis of the formation of a, solid solution of TNT in HNS, rather than a complex of formula TNT2HNS.

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macromolecular drug release in the human body [ 1 , 2 ]. PCL typically has a glass transition temperature of −60 °C and exhibits a melting peak in the region of 60 °C. The temperature at which the crystallisation process proceeds most rapidly is in the region of

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Introduction More than 1,200 articles are published every year in scientific journals that are related to crystallization of glasses. This number was four times larger than 20 years ago. However, most of those articles

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