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Journal of Thermal Analysis and Calorimetry
Authors: Javier Tarrío-Saavedra, Carlos Gracia-Fernández, Jorge López-Beceiro, Salvador Naya, and Ramón Artiaga

modulation frequency (as the DMA T gd is affected by the mechanical frequency) and it is generally measured using the reversing heat flow. Nevertheless, as was mentioned, the TMDSC phase can be also used to measure relaxations. In fact, an increase of the

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34 368 375 Čechurova M, Veverka B 2009: Acta Geod. Geoph. Hung. , 44 (present issue) DMA, Defense Mapping Agency

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. 9 Garrido Pedrosa , AM Souza , MJB Melo , DMA Souza , AG Araujo , AS 2005 J

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Abstract  

The influence of the structure of succinic or glutaric anhydride modified linear unsaturated (epoxy) polyesters on the course of the cure reaction with styrene initiated by benzoyl peroxide (BPO) or the mixture of benzoyl peroxide/tetrahydrophthalic anhydride (BPO/THPA) or benzoyl peroxide/maleic anhydride, as well as viscoelastic properties and thermal behavior of their styrene copolymers have been studied by DSC, DMA, and TGA analyses. Additionally, mechanical properties: flexural properties using three-point bending test and Brinell’s hardness for studied copolymers were evaluated. It was confirmed that the structure of used polyesters had a considerable influence on the course of the cure reaction with styrene, viscoelastic, thermal, and mechanical properties of prepared styrene copolymers. Generally, one or two asymmetrical peaks for the cure reaction of succinic or glutaric anhydride modified linear unsaturated epoxy polyesters with styrene were observed. They were connected with various cure reaction, e.g., copolymerization of carbon–carbon double bonds of polyester with styrene, thermal curing of epoxy groups, polyaddition reaction of epoxy to anhydride groups in dependence of used curing system. In addition, only one asymmetrical, exothermic peak attributed to the copolymerization process of succinic or glutaric anhydride modified linear unsaturated polyesters with styrene was visible. Moreover, the obtained styrene copolymers based on succinic or glutaric anhydride modified linear unsaturated epoxy polyesters were characterized by higher values of
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$E_{{20\,^{\circ}{\text{C}}}}^{\prime}$$ \end{document}
, T g, E″, ν e, E mod, F max, hardness, IDT, FDT but lower ε − F max compared to those values observed for styrene copolymers prepared in the presence of succinic or glutaric anhydride modified linear unsaturated polyesters. This supported to the production of stiffer and more thermally stable polymeric structure of copolymers based on unsaturated epoxy polyesters. Moreover, the copolymers prepared in the use of glutaric anhydride modified linear unsaturated (epoxy) polyesters were described by lower values of
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$E_{{20\,^{\circ}{\text{C}}}}^{\prime}$$ \end{document}
, T g, E″, ν e, E mod, F max, hardness, IDT, FDT but higher ε − F max than those based on succinic anhydride modified linear unsaturated (epoxy) polyesters. The presence of longer aliphatic chain length in polyester’s structure leads to produce more flexible network structure of styrene copolymers based on glutaric anhydride modified linear unsaturated (epoxy) polyesters than those based on succinic anhydride modified linear unsaturated (epoxy) polyesters.
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of the dry matter accumulation (DMA) of sunflower hybrids using the growth analysis method). Növénytermelés 47, 603–612. Napraforgóhibridek tányéronkénti kaszat szárazanyag-felhalmozódásának (TKSZF) vizsgálata

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Baker, D.M.A. (2013): Service Quality and Customer Satisfaction in the Airline Industry: A Comparison between Legacy. American Journal of Tourism Research , 2(1): 67

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Reaction Kinetics, Mechanisms and Catalysis
Authors: M. R. Granados-Uribe, F. J. Lona-Ramírez, C. Pérez-Pérez, J. Barajas-Fernández, V. Rico Ramírez, and G. González-Alatorre

experimental technique, the nitrosation of 1,3-dimethylamine (DMA), whose catalysis by nucleophiles is well documented, was carried out [ 13 ]. Table 2 shows how the initial rate in the nitrosation of DRU remains constant whereas, for the same concentration

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have been studied by means of DSC, TG and DMA analyses. The NADIC/PA modified unsaturated polyesters were prepared in conventional polycondensation process of THPA, maleic anhydride, NADIC/phthalic anhydride and ethylene glycol. The obtained unsaturated

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performed using the dynamic mechanical analyzer DMA Q 800 (TA Instruments, USA), provided with a dual cantilever device with a span length of 35 mm. Runs at 10 Hz were carried out at a constant heating rate of 4 °C/min over the temperature range 20–220 °C

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