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Abstract  

Thermal and thermo-oxidative stability of some poly(siloxane-azomethine)s obtaining starting from bis(formyl-p-phenoxymethyl)tetramethyldisiloxane and different organic diamines have been investigated by TG+DTG+DSC simultaneous analyses performed in argon flow and air static atmosphere, respectively. TG, DTG and DSC curves of each polymer showed three or four successive degradation steps at different temperatures according to the composition of the sample and the gaseous atmosphere in which the thermal analysis was performed. For each process, the following parameters were evaluated: total mass loss, temperature corresponding to the maximum reaction rate, maximum reaction rate, temperature corresponding to certain mass loss. In order to determine the thermal and thermo-oxidative stabilities of investigated polymers, the following values were determined: T x% — temperature corresponding to x% mass loss, and %Δm T — mass loss at a given temperature T. The obtained orders of stability were correlated with the structure of investigated polymers.

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Journal of Thermal Analysis and Calorimetry
Authors: R. A. Candeia, F. S. M. Sinfrônio, T. C. Bicudo, N. Queiroz, A. K. D. Barros Filho, L. E. B. Soledade, I. M. G. Santos, A. L. Souza and A. G. Souza

work aims at evaluating the thermo-oxidative stability of methyl and ethyl soybean biodiesels as a function of oxygen exposition time, aging test temperature, and long-term storage. The oxidative processes were identified by means of absolute

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expected to provide improved thermal stability, elongation, and flexibility to the PU. The objective of this work was to systematically evaluate the thermal behavior and thermo-oxidative stability of lignin-based polyurethane, and their kinetics

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nitrogen atmosphere as ranging from 260 to 400 °C [ 11 , 12 ]. The main aim of this study is the evaluation of the thermal and thermo-oxidative stability of DPP derivates with para-substituted phenyl groups and partially substituted NH

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Journal of Thermal Analysis and Calorimetry
Authors: N. Santos, J. Santos, F. Sinfrônio, T. Bicudo, I. Santos, N. Antoniosi Filho, V. Fernandes and A. Souza

Abstract  

The babassu (Orbignya Phalerata Mart.) biodiesel has lauric esters as main constituents, resulting in high oxidative stability and low cloud and freezing points. In order to reduce these side effects, the saturated ethyl esters content was reduced by means of winterization process. The TMDSC and PDSC techniques were used to verify the thermal and oxidative stabilities of the ethyl babassu biodiesel. During the heating stage, the winterized solid phase of ethyl esters presented an endothermic transition associated to the solidification process. This behavior was not observed for the liquid winterized FAEE, confirming the efficiency of the winterization process.

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Abstract  

The crystallization and melting behavior of PP/CaCO3 nanocomposites during thermo-oxidative degradation process were studied using differential scanning calorimetry and X-ray diffraction. The results indicated that addition of nano-CaCO3 and compatibilizer significantly reduced the thermo-oxidative stability of PP. Before degradation, thermal aging resulted in an increase in the melting temperature and crystallinity of PP due to the annealing crystallization. Thermo-oxidative degradation decreased the melting temperature and increased melting range, and caused an increase in crystallinity of PP due to the chemi-crystallization. The investigation also indicated that the influence of degradation on the small crystals were much more significant than that on the large ones.

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Sunflower biodiesel

Use of P-DSC in the evaluation of antioxidant efficiency

Journal of Thermal Analysis and Calorimetry
Authors: M. L. A. Tavares, N. Queiroz, I. M. G. Santos, A. L. Souza, E. H. S. Cavalcanti, A. K. D. Barros, R. Rosenhaim, L. E. B. Soledade and A. G. Souza

, Bicudo , TC , Santos , IMG , Antoniosi Filho , NR , VJ Fernandes Jr , Souza , AG . Thermo-oxidative stability and cold flow properties of babassu biodiesel by P-DSC and TMDSC techniques . J Therm Anal Calorim . 2009 ; 97 : 611 – 614 . 10

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Journal of Thermal Analysis and Calorimetry
Authors: Francisco J. N. Maia, Viviane G. Ribeiro, Claudenilson S. Clemente, Diego Lomonaco, Pedro H. M. Vasconcelos and Selma E. Mazzetto

, respectively ( Fig. 2 ), and evaluating their thermo-oxidative stability. As well, their antioxidant capacities upon mineral oils (NH10 and NH20) were evaluated by thermogravimetric analysis (TG/DTG). Phosphorylated products from cardol have been patented [ 17

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epoxy carbon fiber composites. Their flammability behaviors were investigated by cone calorimeter. The thermo-oxidation stability and low gas permeability of buckypapers or CNF nanofiber are key roles in improving flame-retardant properties of composites

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