Modulation differential scanning calorimeter

The differential scanning calorimeter (DSC) works on a technique that detects physicochemical transition in a system by measuring the amount of heat absorbed or released as the sample is heat across its suspected transition range. The heat absorbed or released from a sample of known mass compared with that of an empty reference pan. Modulated differential scanning calorimeter (mDSC) works on an advanced technology version of DSC, where the signal quality has been improved using... 

Vasanthavada, M., Z. V fong, Y. Joshi, and M. S. Kislalioglu. 2002. Comparison of the utility of thermally stimulated current and modulated differential scanning calorimeter to study sub-glass transition molecular motions of poly(vinylpyrrolidone). Paper presented at AAPS Annual Meeting, Toronto, October 8, 2002. 

The compositions of the composites were determined simply by weighing the tared solid sample. Melting endotherms and glass transition temperatures were determined using a TA Instruments 2910 modulated differential scanning calorimeter (DSC) operated with a 3°C/min ramp rate, a 0.75 °C oscillation amplitude, and a 60-s oscillation period. 

Varma-Nair, M. Wunderlich, B. Nonisothermal heat capacities and chemical reactions using a modulated differential scanning calorimeter. J. Therm. Anal. 1996, 46, 879-892. 

The Tg of the PS estimated from thermal analysis, Tgosc, has been obtained from Modulation Differential Scanning Calorimeter (MDSC) curves at a rate of 2.0 K/min. The transition temperatures, Tgosc. Ts.omXe. and Ts.omXi are plotted against M in Fig. 8.4. The most successful model for the description of the... 

DTA as well as power compensation DSC instruments, and is called temperature modulated DSC, or TMDSC. The following trade marks are used by different TA instrument manufacturers for their temperature modulated differential scanning calorimeters Modulated DSC (MDSC ) of TA Instruments Inc., Oscillating DSC (ODSC ) of Seiko Instruments Inc., Alternating DSC (ADSC ) of Mettler-Toledo Inc. and Dynamic DSC (DDSC ) of Perkin-Elmer Corp. 

Very thin films, around 10 [tm thick, are prepared for diffusivity measurements. Great care is taken to make sure that the physical properties of these films (expanded by air blowing) are similar to those of PET bottles, by using thermal mechanical analysis (TMA) and modulated differential scanning calorimeter (MDSC). 

Glass transition temperature measurements on the solutions of Zdol in PFOM were performed in a temperature-modulated differential scanning calorimeter. 

Thermal analysis of polymers and blends was performed on a TA Instruihents 2910 Modulated Differential Scanning Calorimeter (DSC). Modulated DSC analysis was used to characterize the morphological properties of the D,L-PLA and PCL PDO blends. During the DSC scan, the sample was heated to 70°C at l C/min linear ramp while the modulation was at an amplitude of +/- 1 C every 30 seconds. 

DSC scans were carried out on a 10°C/min between 0°C and 320 °C by a TA Modulated Differential Scanning Calorimeter model 2920. 

There are many excellent differential scanning calorimeter systems available which can be used to measure the specific heat which, when combined with the sample density can be used to give c . The thermal diffusivity (which can be important for thermal imaging systems if the target is not reticulated) can be measured directly on a pyroelectric substrate using the laser intensity modulation method described by Lang [23],... 

Kwon, Y.K. Andorsch, R. Pyda, M. Wunderlich, B. Multifrequency saw-tooth modulation of a power-compensated differential scanning calorimeter. Thermochim. Acta 2001, 367 (8), 203-215. 

Several modifications of differential scanning calorimeters, DSC, have been developed during the last few years for the measurement of enthalpies of phase changes [194-197] and Knudsen cells have been used as calorimetric cells. Modulated temperature thermogravimetry has also been proposed for the measurement of enthalpies of sublimation [198]. 

Pak J, Wunderlich B (2001) Heat Capacity by Sawtooth-modulated, Standard Heat-flux Differential Scanning Calorimeter with Close Control of the Heater Temperature. Thermochim Acta 367/368 229-238. 

Kwon YK, Androsch R, Pyda M, Wunderlich B (2001) Multi-frequency Sawtooth Modulation of a Power-compensation Differential Scanning Calorimeter. Thermochim. Acta 367/368 203-215. 

Pak, (. and Wimderlich, B. (2001) Heat capacity by sawtooth-modulated, standard heat-flux differential scanning calorimeter with dose control of the heater temperature. Thermochim. Acta, 367/368, 229-238. 

El 142, Standard Terminology Relating to Thermophysical Properties E1952, Standard Test Method for Thermal Conductivity and Thermal Dif-fusivity by Modulated Temperature Differential Scanning Calorimeter E2069, Standard Test Method for Temperature Calibration on Cooling for Differential Scanning Calorimeters... 

Figure 18 Schematic illustration showing the general configurations of the two types of differential scanning calorimeter sample chamhers. (a) Constant heat flow into the sample chamber (b) modulated heat flow to maintain specific temperature ramp.

Differential scanning calorimetry (DSC) has proven to be a very reliable technique to obtain heat capacity at elevated temperatirres in a reasonably short time. DSC also allows the study of the kinetics of nonequilibrium transitions in a wide dynamic range. Because of its simplicity and ease of use, DSC is widely applied in polymer science and is the focus of this chapter. Recent additions such as temperature modulation and fast scanning, both making additional use of chip-based calorimeters, are also discussed in detail. 

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