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Phenolics Differential Thermal Analysis

Thermal properties of several chlorinated phenols and derivatives were studied by differential thermal analysis and mass spectrometry and in bulk reactions. Conditions which might facilitate the formation of stable dioxins were emphasized. No two chlorinated phenols behaved alike. For a given compound the decomposition temperature and rate as well as the product distribution varied considerably with reaction conditions. The phenols themselves seem to pyro-lyze under equilibrium conditions slowly above 250°C. For their alkali salts the onset of decomposition is sharp and around 350°C. The reaction itself is exothermic. Preliminary results indicate that heavy ions such as cupric ion may decrease the decomposition temperature. [Pg.26]

On the basis of an IR study of some s-triazines and HA systems, several authors reported that ionic bonding took place between a protonated secondary amino group of the s-triazine and a carboxylate anion on the HA [17,146,147]. Successive studies, mainly conducted by IR spectroscopy, confirmed previous results and also provided evidence for the possible involvement of the acidic phenol-OH of HA in the proton exchange of the s-triazine molecule [17, 146-150]. Differential thermal analysis (DTA) curves measured by Senesi and Testini [146, 147] showed an increased thermal stability of the HA-s-triazine complexes, thus confirming that ionic binding took place between the interacting products. [Pg.133]

In the case of highly cross-linked material, water is not released until above 400°C, and decomposition starts above 500°C as confirmed using differential thermal analysis (DTA).55 The amount of char depends on the structure of phenol, initial cross-links, and tendency to cross-link during decomposition. The main decomposition products may include methane, acetone, CO, propanol, and propane. [Pg.28]

The constitnents of binary phenol mixtnres can be identihed by differential thermal analysis of a sample to which any of the aroyl chlorides 184-186 has been added. The thermogram is compared with a bank of differential thermograms of phenols, binary phenol mixtures and binary phenol derivatives. Most snch systems show weU-resolved endotherms corresponding to the melting points of the phenols and their acylated derivatives. The method is proposed for rapid identification of phenols in the solid state . [Pg.1002]

Thus the kinetics of thermal oxidative degradation has been studied by thermogravimetry" and the anti-oxidant ability of phenol and phosphorus derivatives have been evaluated by differential thermal analysis. Studies of the effect of red phosphorus and phosphorus and bromine"- on d adation bdiaviour and their role as fire-proofing agents has been described. Bis(ketimines) have been evaluated as reactive additives for viscosity stabilization in the melt."... [Pg.87]

Proton NMR, differential thermal analysis (DTA), thermogravimetric analysis (TGA), and capacitance versus cure time have also been reviewed in connection with analyses of phenolic resins [27]. [Pg.53]

Cure rates of phenolic resins have been studied by differential thermal analysis and infrared spectroscopy [86]. [Pg.77]

As indicated in the previous sections, the antioxidant content in plastic material is often determined by chromatographic methods. Another widely used technique for polymer characterization is thermal analysis with differential scanning calorimetry (DSC). When the oxygen induction time (OIT) for a sample containing a phenoHc antioxidant is measured, a significant oxidative exothermic response is obtained in the DSC when all the phenolic antioxidant in a sample is consumed. The OIT is thus directly related to the antioxidant content in the material and to the stabihzing function, i.e. the antioxidant efficiency in the sample, if the consumption of phenolic antioxidants obeys zero-order kinetics at the temperature used [44]. Table 1 shows the amount of the antioxidant Irganox 1081 in polyethylene (PE) determined by HPLC and extraction by microwave assisted extraction (MAE),... [Pg.126]

Differential scanning calorimetry (DSC), DMA and TG were used by Tabaddor and co-workersl l to investigate the cure kinetics and the development of mechanical properties of a commercial thermoplastic/ thermoset adhesive, which is part of a reinforced tape system for industrial applications. From the results, the authors concluded that thermal studies indicate that the adhesive was composed of a thermoplastic elastomeric copolymer of acrylonitrile and butadiene phase and a phenolic thermosetting resin phase. From the DSC phase transition studies, they were able to determine the composition of the blend. The kinetics of conversion of the thermosetting can be monitored by TG. Dynamic mechanical analysis measurements and time-temperature superposition can be utilized to... [Pg.600]


See other pages where Phenolics Differential Thermal Analysis is mentioned: [Pg.26]    [Pg.540]    [Pg.511]    [Pg.162]    [Pg.163]    [Pg.154]    [Pg.155]    [Pg.682]    [Pg.361]    [Pg.71]    [Pg.607]    [Pg.362]    [Pg.24]    [Pg.2526]    [Pg.87]    [Pg.2506]    [Pg.430]    [Pg.408]    [Pg.322]    [Pg.487]   
See also in sourсe #XX -- [ Pg.683 , Pg.684 ]




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