Differential scanning calorimetric DSC measurements

R)- and S- CHT A [Tf2N]" are liquid at room temperature, and results from differential scanning calorimetric (DSC) measurements indicate that they have glass transition temperature of -58.4°C. Results from thermal... 

Differential Scanning Calorimetric (DSC) Measurements of Soaked Pastes Cured at 90 °C... 

Figure 19.13a-d presents differential scanning calorimetric (DSC) measurements to determine the type of water content of SP63, SP63/2.5CL, SP63/2.5CL/5.0TAP, and Nation 12 membranes. This measurement is crucial to further understand the water-retention capability of the prepared PEMs. 

Fig. 1.45. Schema of a differential scanning calorimetric (DSC) apparatus. Gerate DSC 821 . Temperature range with LN2 cooling -150 °C to 500 °C accuracy of temperature 0.2 °C resolution 0.7 gW in the measuring range of +/-350 mW cooling rate from +100 °C to -100 °C approx. 13 °C/min size of sample, several mg to 200 mg.

The first directly-measured evidence that C—H bond rupture in the methyl group is the rate-determining step in the thermal de compn of TNT has been obtained with isothermal differential scanning calorimetric (DSC) analysis using deuterium isotope effects (Ref 96), DSC analysis has also been used to determine the kinetic parameters of thermal decompn (Ref 92). Others (Ref 101) have also studied the mechanism of the reaction using the deuterium isotope effect. Data are available on heat generation in... 

In this work, we describe an automated differential scanning calorimetric (DSC) technique that can be used to measure polymerization kinetics for formation of urethane block polymers. The same technique is also used to measure phase separation during formation of polyurethane elastomers and the effect that separation has on the polymerization. The elastomer formulations consisted of modified liquid p,p -diphenyImethyl diisocyanate (MDI), 1,4-butanediol and an (oxypropylene-oxyethylene) macroglycol for the soft segment. 

Figure 16.2 shows a sample temperature-heat flow differential scanning calorimetric (DSC) curve obtained for high-density polyethylene (HDPE) using a Perkin Elmer DSC-7 instrument illustrating the measurement of the and the heat of melting in a single run. 

The specific T] can be measured by different techniques, such as turbidity analysis or calorimetric methods (Fig. 2). The first method is characterized by a turbidity profile showing a sharp step, with T, taken to be the temperature that shows a 50% change in the relative turbidity shape. In contrast, differential scanning calorimetry (DSC) measurements are always characterized by a broad peak covering 20 °C or more. In this case, T, can be considered as either the onset or the peak temperature. The T, values obtained by these methods usually differ because of the influence of several factors [26]. 

The melting point of the copolymer was determined from the peak of the differential scanning calorimetric(DSC) spectra, measured with a Dupont apparatus. DSC measurements were made at a heating rate of 10°C/min. The samples were melted at 200 C. 

Methods often used for determining the gel point include the inverted test tube method, fallen ball method, viscoelasticity measurement, and differential scanning calorimetric (DSC) method. In what follows experimental studies on the gel point and melting point from the viewpoint of the lost fluidity of sols will be individually introduced, with an emphasis on experimental procedures. 

FIGURE 2.29 An example of differential scanning calorimetric (DSC) data for a thermotropic liquid crystal (8CB) measured on a heating run of 207min. Two peaks can be observed. The first peak with an onset at 32.16° is the smectic-A-to-nematic phase transition, and the second peak at 39.56° is the nematic-to-isotropic liquid phase transition. Delta H Is the enthalpy of the transitions. 

Thermogravimetric- (TG) and differential scanning calorimetric- (DSC) studies were carried out using a Mettler TA 2000C thermoanalyzer. Measurements were performed under air with a heating rate of 10 K min. ... 

The worst hazard scenarios (excessive temperature and pressure rise accompanied by emission of toxic substances) must be worked out based upon calorimetric measurements (e.g. means to reduce hazards by using the inherent safety concept or Differential Scanning Calorimetry, DSC) and protection measures must be considered. If handling hazardous materials is considered too risky, procedures for generation of the hazardous reactants in situ in the reactor might be developed. Micro-reactor technology could also be an option. Completeness of the data on flammability, explosivity, (auto)ignition, static electricity, safe levels of exposure, environmental protection, transportation, etc. must be checked. Incompatibility of materials to be treated in a plant must be determined. 

Thermodynamic data of the epoxy polymerization with triphenylsulfonium salt photoinitiators can be obtained by differential scanning calorimetric measurements (DSC). Figure 6 shows the DSC diagram of the polymerization of Bisphenol-A di-glycidylether with triphenylsulfonium hexafluorophosphate, irradiation being carried... 

Differential scanning calorimetry (DSC) is a calorimetric method that finds widespread use in many fields, including protein dynamics, polymers, pharmaceuticals, and inorganic materials. DSC measures energy (heat) flow into a sample and a reference substance as a function of controlled increase or decrease of temperature. In a typical power-compensated DSC (Fig. 3.2), the sample and reference are placed on metal pans in identical furnaces each containing a platinum resistance thermometer (thermocouple) and heater. During a thermal transition (e.g., when a physical change in the sample occurs),... 

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