This presentation summarizes differential scanning calorimetry (DSC), which measures the heat flow into or out of a sample during heating or cooling. DSC can determine phase transitions like glass transitions, melting points, and crystallization temperatures. It works by heating a sample and reference simultaneously while measuring any heat differential. Factors like heating rate, sample size, and instrumentation can affect results. DSC is useful for characterizing polymers and other materials.
In this slides contains principle and instrumentation of Differential Scanning Calorimeter (DSC).
Presented by: N Poojitha. (Department of pharmaceutics),
RIPER, anantapur.
In this slides contains principle and instrumentation of Differential Scanning Calorimeter (DSC).
Presented by: N Poojitha. (Department of pharmaceutics),
RIPER, anantapur.
Differential Thermal Analysis (DTA),principle of DTA, working of DTA, instrumentation of DTA, thermogram factors affecting DTA curve, advantages and disadvantages, applications of DTA, Thermogravimetry (TG),types of TG, principle of TG, working of TG, instrumentation of TG, thermogram of TG, factors affecting TG curve, advantages and disadvantages, applications of TG
An Infrared spectrum represents a fingerprint of a sample with absorption peaks which correspond to the frequencies of vibrations between the bonds of the atoms making up the material-Because each different material is a unique combination of atoms, no two compounds produce the exact same spectrum, therefore IR can result in a unique identification of every different kind of material!
In DSC the heat flow is measured and plotted against temperature of furnace or time to get a thermo gram. This is the basis of Differential Scanning Calorimetry (DSC).
The deviation observed above the base (zero) line is called exothermic transition and below is called endothermic transition.
EXPERIMENT PARAMETERS OF DIFFERENTIAL SCANNING CALORIMETRY (DSC)Shikha Popali
THE EXPERIMENTAL PARAMETERS USED IN DSC INCLUDING SAMPLE PREPARATION , EXPERIMENTAL CONDITIONS, CALIBRATION OF APPARATUS, INSTRUMENTS, HEATING RATES AND TEMPERATURES, COOLING RATES,RESOLUTION, ALSO SOURCE OF ERRORS.
DSC ( differential scanning calorimetry) is a thermo-analytical technique for qualitative and quantitative assessment of our analyte on the basis of heat provision and heat withdrawn from pan with compensation of both pans.
Fourier transform infrared spectroscopy: advantage and disadvantage of conventional infrared spectroscopy, introduction to FTIR ,principle of FTIR, working, advantage, disadvantage and application of FTIR.
Differential Thermal Analysis (DTA),principle of DTA, working of DTA, instrumentation of DTA, thermogram factors affecting DTA curve, advantages and disadvantages, applications of DTA, Thermogravimetry (TG),types of TG, principle of TG, working of TG, instrumentation of TG, thermogram of TG, factors affecting TG curve, advantages and disadvantages, applications of TG
An Infrared spectrum represents a fingerprint of a sample with absorption peaks which correspond to the frequencies of vibrations between the bonds of the atoms making up the material-Because each different material is a unique combination of atoms, no two compounds produce the exact same spectrum, therefore IR can result in a unique identification of every different kind of material!
In DSC the heat flow is measured and plotted against temperature of furnace or time to get a thermo gram. This is the basis of Differential Scanning Calorimetry (DSC).
The deviation observed above the base (zero) line is called exothermic transition and below is called endothermic transition.
EXPERIMENT PARAMETERS OF DIFFERENTIAL SCANNING CALORIMETRY (DSC)Shikha Popali
THE EXPERIMENTAL PARAMETERS USED IN DSC INCLUDING SAMPLE PREPARATION , EXPERIMENTAL CONDITIONS, CALIBRATION OF APPARATUS, INSTRUMENTS, HEATING RATES AND TEMPERATURES, COOLING RATES,RESOLUTION, ALSO SOURCE OF ERRORS.
DSC ( differential scanning calorimetry) is a thermo-analytical technique for qualitative and quantitative assessment of our analyte on the basis of heat provision and heat withdrawn from pan with compensation of both pans.
Fourier transform infrared spectroscopy: advantage and disadvantage of conventional infrared spectroscopy, introduction to FTIR ,principle of FTIR, working, advantage, disadvantage and application of FTIR.
The techniques in which some physical parameters of the systems are determined and /or recorded as a function of temperature.
DSC is a thermal technique in which differences in heat flow into a substance and a reference are measured as a function of sample temperature while the two are subjected to a controlled temperature program.
Differential Scanning Calorimetry, or DSC, is a thermal
analysis technique that looks at how a material’s heat
capacity (Cp) is changed by temperature. A sample of
known mass is heated or cooled and the changes in its
heat capacity is tracked as changes in the heat flow.
This allows the detection of transitions like melts, glass
transitions, phase changes, and curing. Because of this
flexibility, DSC is used in many industries including
pharmaceuticals, polymers, food, paper, printing, manufacturing, agriculture, semiconductors, and electronics
as most materials exhibit some sort of transition.
The investigation of thermodynamic properties and reactivity yields interesting insights into the chemistry of newly synthesized substances. With thermal analysis extensive information can be gained from small samples (often only a few milligrams). In addition, the data obtained by thermal analysis can be used to plan and optimize a synthesis. Among the most important applications are identification and purity analysis, and the determination of characteristic temperatures and enthalpies of phase transitions (melting, vaporization), phase transformations, and reactions. Investigations into the kinetics of consecutive reactions and decomposition reactions are also possible. With the instruments available today such analyses can usually be performed quickly and easily. In this review the fundamentals of thermoanalytical methods are described and illustrated with selected examples of applications to low and high molecular weight compounds.
Introduction:
During the past few years, the methods of thermal analysis have been widely accepted in analytical chemistry.
The term thermal analysis incorporates those techniques in which some physical parameter of the system is determined and/or recorded as a function of temperature.
Thermal analysis has been used to determine the physical and chemical properties of polymers, drugs and geological materials.
A calorimeter measures the heat into or out of a sample.
A differential calorimeter measures the heat of sample relative to a reference.
A differential scanning calorimeter does all of the above and heats the sample with a linear temperature ramp (developed by E. S. Watson and M. J. O'Neill in 1962).
DSC is a technique in which the difference in the amount of heat required to increase the temperature of a sample and reference are measured as function of temperature.
Both the sample and reference are maintained at nearly the same temperature throughout the experiment.
Only a few mg of material are required to run the analysis.
DSC is the most often used thermal analysis method, primarily because of its speed, simplicity, and availability.
Principle:
When a sample undergoes a physical transformation such as a phase transition, more or less heat will need to flow to it than to the reference (typically an empty sample pan) to maintain both at the same temp. Whether more of less heat must flow to the sample depends on whether the process is exothermic or endothermic.
For e.g.as a solid sample melts to a liquid it will require more heat flowing to the sample to increase its temp. At the same rate as the reference. This is due to the absorption of heat by the sample as it undergoes the endothermic phase transition from solid to liquid.
Likewise, as the sample undergoes exothermic processes (such as crystallization) less heat is required to raise the sample temp.
By observing the difference in heat flow between the sample and reference, DSC is able to measure the amount of heat absorbs or release during such transition.
Advantages:
It can be used at a very high temperature.
High sensitivity
High resolution obtained
Stability of the material
Flexibility in sample volume/form
Limitations:
It is unsuitable for two-phase mixtures
Does not detect gas generation
Uncertainty of heats of fusion and transition temperatures.
Applications:
Oxidative stability
Crystallinity
Drug analysis
Heat capacity
Purity
Schematic Arrangement of DSC Apparatus
Heat Flux DSC
Power Compensated DSC
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Differential Scanning Calorimetry
this device help you for reverse engineering by using this device you can know about compounds glass transition temp or melting temp.
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4. THERMALANALYSIS
Thermal analysis is a branch of materials science & a group of analysis which
study the property of material when the change with temperature
7. HISTORY
• The technique was developed by E.S. Watson and M.J. O'Neill in 1960,
and introduced commercially at the Pittsburgh Conference on Analytical
Chemistry and Applied Spectroscopy in 1963.
• This technique is used to study what happens to polymers/samples upon
heating.
• calorimeter , it is one who measures the heat in or out of the sample.
8. INRODUCTION
Measure the difference in the heat flow between the sample and the reference
material.
Sample
material under observation
Reference material
control 0r standard used
Heat flow
heat capacity
9. INTRODUCATION
DEFINATION
It is a technique in which the energy necessary to establish a zero temperature
difference between the sample & reference material is measured as a function of
temperature.
• Here, sample & reference material are heated by separate heaters in such a way that
their temp are kept equal while these temp. are increased or decreased linearly.
• During heating two types of reactions can be take place one is the endothermic and
the other is the exothermic.
10. PRINCIPLE
Sample and an inert reference heated separately, with the power supply to
the sample heater variable so that the temperature difference can be
maintained at zero even when endothermic or exothermic changes occur.
The difference in power supplied to the two heaters is monitored as the
analytical signal (DE). Alternatively, the differential heat flow to sample
and standard when they are heated from the same source is monitored.
11. INSTRUMENTATION
• Sample and reference crucibles with separate heaters. Thermocouples with
feedback to sample heater so that the power is varied to maintain DT = 0.
• TWO PANS
• HEATERS
• OUTPUT DEVICE
• THERMOGRAM
13. WORKING OF DSC
Step 3
Setup parameter for experiment
Step 2
Sample preparation
Step 1
Starting up instrument
14. STEP 1.STARTING UP INSTRUEMENT
• Turn on the calorimeter and increase cell pressure.
• Fill cleaning agent reservoirs to the correct volume.
• Fill cleaning agent reservoirs to the correct volume
15. STEP 2. SAMPLE PREPARATION
• Accurately-weigh samples (~3-20 mg)
• Small sample pans
• • Material should completely cover the bottom of the pan to ensure good
thermal contact
• • Avoid overfilling the pan to minimize thermal lag from the bulk of the
material to the sensor.
16. STEP 3 SETUP PARAMETERS FOR
EXPERIMENT
• Enter sample information into the software.
• Set cleaning options
• Set starting temperature of the experiment based on the sample.
• Set experiment final temperature. This is dependent on the sample.
• Select the scan rate for the experiment.
• To preserve the cells in the calorimeter set the thermostat to 10 °C post
experiment
• Before starting the experiment, double check all parameters and ensure they
meet required guidelines for the scope of the experiment
17. WORKING
There are two pans, In sample pan, polymer is added, while the other, reference
pan is left empty Each pan sits on top of heaters which are controlled by a
computer .The computer turns on heaters, and let them heat the two pans at a
specific rate. .The computer makes absolutely sure that the heating rate stays
exactly the same throughout the experiment.
18. DSC CURVE
The result of a DSC experiment is a curve of heat flow versus temperature
or versus time.
Graph is used to determine change in heat flow (enthalpy) .it can be calculate
by following equation.
∆𝑯 = 𝑲𝑨
Where ΔH is the enthalpy of transition, K is the calorimetric constant, A is
the area under the peak.
20. DSC CURVE
• The Glass Transition Temperature
• Melting
•crystallization
21. Glass transition temperature
• Heating the polymer to a certain temperature, plot will shift downward
suddenly.
• This means there is more heat flow. There is an increase in the heat capacity
of the polymer. This happens because the polymer has just gone through the
glass transition. Because of this change in heat capacity that occurs at the
glass transition, we can use DSC to measure a polymer's glass transition
temperature.
22.
23. crystallization
• After glass transition, the polymers have a lot of mobility
• when they reach the right temperature, they will give off enough energy to
move into very ordered arrangements, which is called crystals.
• Also, because the polymer gives off heat when it crystallizes, we call
crystallization is an exothermic transition
24.
25. Melting
• If we heat our polymer past its Tc , eventually we'll reach another
thermal transition, called melting.
• When we reach the polymer's melting temperature, Tm, the
polymer crystals begin to fall apart, that is they melt .
26.
27. FACTORS
• There are two types of factor that effect DSC
1.Instrumentation factors
2.Sample nature
29. 1. TEMPERATURE CONTROL
The starting and final temperature should be chosen.
Start temperature should be at room temperature
Final temperature any point before degradation
30. 2.HEATING RATE
Heating rate 5 to20 ˚C/min
Cooling rate 5 to 10˚C /mint
example
Nylon-66
Melting behavior change
33. TYPES OF DSC INSTRUMENT
HEAT FLUX DSC
• sample holder is composed of al ,
pt.
• Furnace is one block for both
sample and reference cells
POWER COMPENSATED DSC
• Sample holder: Aluminum,
platinum, stainless steel pans
• separate blocks for sample and
reference cells.
34. APPLICATIONS
• Widespread study of thermal properties on an extensive range of sample
types.
• Determination of phase transition
• Determination of melting and boiling point
• Thermal stability
• Rate of curve
35. DISADVANTAGES
• Usually limited to small sample sizes.
• Thermogram are often complex and thus difficult to interpret fully
• Very sensitive to any change
• Cant optimize both senstivty and resolution in one experiment
36. CONCLUSION
• Differential scanning calorimetry (DSC) is an effective analytical tool to
characterize the physical properties of a polymer. DSC enables
determination of melting, crystallization, and mesomorphic transition
temperatures, and the corresponding enthalpy and entropy changes, and
characterization of glass transition and other effects that show either changes
in heat capacity or a latent heat.
37. REFERENCES
Serrano, N., Díaz-Cruz, J. M., Ariño, C., & Esteban, M. (2010). Stripping
analysis of heavy metals in tap water using the bismuth film
electrode. Analytical and bioanalytical chemistry, 396(3), 1365-1369.
Edition, F., Fifield, F. W., & Kealey, D. Principles and Practice of
Analytical Chemistry.
Renfrew, C., Bahn, P. G., & Bahn, P. G. (1991). Archaeology:
theories, methods and practice (Vol. 2). London: Thames and
Hudson.
