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Abstract

Bi2Te3 nanoparticles (NPs) have been synthesized at 50 °C by a low-cost wet chemical route. The structural properties of product sample were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy. Thermal properties of product sample were investigated by differential scanning calorimetry (DSC), thermogravimetric (TG), and transient plane source techniques. The XRD and selected area electron diffraction of Bi2Te3 NPs result showed the polycrystalline nature with a rhombohedral (R3m) structure of the nanocrystallites. The average grain size of Bi2Te3 NPs was found to be about 30 nm by XRD and TEM measurements. DSC result shows one endothermic peak and one exothermic peak. TG result shows that only 48 % mass loss has occurred in Bi2Te3 sample. The obtained lower thermal conductivity of Bi2Te3 NPs is about 0.3 W m−1 K−1 at room temperature, which is caused by considering the crystalline nature of this material.

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Abstract  

This article describes the test results of thermal properties and flammability of the unconventionally cross-linked blends of chlorosulfonated polyethylene (CSM) and butadiene–styrene rubber (SBR) by means of zinc oxide or nano-zinc oxide. The thermal curves have been interpreted from the point of view of the chemical transitions of elastomers and their blends. It has been found that the content of combined chlorine in CSM exerts a significant influence on the cross-linking kinetics of CSM/SBR blends, their thermal properties and flammability.

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Combustion and thermal properties of paper honeycomb

Treatment of phosphorus-based flame retardant agents

Journal of Thermal Analysis and Calorimetry
Authors: Dong-Ho Rie, Sung-Woong Moon, and Kyung-Bum Lim

impossible [ 4 ]. Accordingly, the present research has performed basic research on a recycling possibility of building’s interior materials by analyzing combustion and thermal properties according to flame retardant treatment of paper honeycomb and

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and thermal properties of kenaf and hemp bast fibre composites: part 1 - polyester resin matrix . Compos Sci Technol. 2004 ; 64 : 1219 – 30 http://dx.doi.org/10.1016/j.compscitech.2003.10.001 . 22

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Journal of Thermal Analysis and Calorimetry
Authors: G. Janowska, A. Kucharska-Jastrzabek, A. Kasiczak, and W. M. Rzymski

type and quantity of metal compound used for cross-linking [ 3 – 5 ]. Currently produced and commercially available CSMs are characterized by different cross-linking capabilities, thermal properties, and flammability [ 6 , 7 ], which is

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Journal of Thermal Analysis and Calorimetry
Authors: M. Prochon, G. Janowska, A. Przepiorkowska, and A. Kucharska-Jastrzabek

Table 3 Thermal properties of elastomer and its composites Sample

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Journal of Thermal Analysis and Calorimetry
Authors: G. Janowska, A. Kucharska-Jastrzabek, W. M. Rzymski, and A. Pajak

with MgO. These phenomena are connected both with the total Cl-content in the system and the specific action of MgO incorporated into the blends studied. The obtained results are the different thermal properties and the combustibility of CSM of

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Journal of Thermal Analysis and Calorimetry
Authors: A. V. Nikolaev, A. A. Opalovsky, V. E. Fedorov, and T. D. Fedotova

Data are presented on the properties of alkali metal and alkaline earth hydrofluorides. Melting, thermal decomposition and interaction of hydrofluorides with various classes of inorganic substances are discussed. Some regularities of changes in thermal properties within the sequences of the above hydrofluorides are established. Future directions of research in this field are outlined.

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Thermal properties of polylactides

Effect of molecular mass and nature of lactide isomer

Journal of Thermal Analysis and Calorimetry
Authors: J. Ahmed, J. Zhang, Z. Song, and S. Varshney

Abstract  

A thermal analysis of a series of polylactides (PLA) was carried out based on the number of average molecular mass (M n), and the nature of isomer (D, L and DL). It is confirmed that the glass transition temperature (T g) of PLA increased as a function of molecular mass irrespective of isomer type except sample with a high polydispersity index. The melting temperature (T m) and enthalpy of crystal fusion (ΔH f) of L-isomer increased as the M n was increased from 1100 to 27500. The degree of crystallinity (χc%) increased as a function of molecular mass. However no crystallization peak was detected in the lower molecular mass range (550–1400). The non-isothermal crystallization behavior of the PLA melt was significantly influenced by the cooling rate. Both D and L isomers exhibited insignificant difference in thermal properties and DL lactides exhibited amorphous behavior at identical molecular masses. Change in microstructure showed significant difference between two isomers. Analysis of the FTIR spectra of these PLA samples in the range of 1200–1230 cm−1 supported DSC observation on crystallinity.

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Abstract  

Thermal properties of new biocomposites prepared from modified starch matrix reinforced with natural vegetable fibres were studied. DSC and TG methods were applied to study thermal behaviour of biocomposites. Biocomposites were obtained in the laboratory twin-screw extruder. Two kinds of natural fibres were used, i.e. flax and cellulose in the amount of 0–40 mass%. DSC curves of biocomposites reveal glass transition temperature, attributed to the amorphous nature of the plasticized starch matrix. In general, incorporating natural fibres into modified starch matrix leads to an increase in glass transition temperature. Thermal degradation of modified starch matrix and cellulose reinforced biocomposites proceeds in three steps, whereas the degradation process of flax reinforced biocomposites occurs in two steps. For unreinforced matrix as well as for all biocomposites, regardless of type and amount of reinforcement, the major mass loss is observed at the temperature above 300C. The increase in thermal stability with introduction of natural fibre is observed for both flax and cellulose reinforced biocomposites.

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