1. Fundamentals And applications Of Thermal Analysis

2. Objectives:
To explain principle of different types of thermal techniques.
To describe instrumentation of different types of thermal techniques
To distinguish between DSC,DTA & TGA
To explain application of thermal method

3. Introduction:
Thermal analysis is a branch of material science where the properties of materials are studied as they change with temperature.
When matter is heated it undergoes certain physical and chemical changes. These physical and chemical take place over a wide temperature range.
Physical changes such as melting or boiling may occur at widely varying temperature, depending on material involve.
Chemical changes such as decomposition or reaction may also take place at very different temperatures.
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no-2-701

4. Definition of Thermal Analysis
A branch of materials science where the properties of materials are studied as they change with temperature.
Ref-Skoog, Douglas A., F. James Holler and Timothy Nieman (1998). Principles of Instrumental Analysis (5 ed.). New York. pp. 805.

5. NO
Technique Name
Abbreviation
Instrument Apply
Parameter Measure
Graph 1
Thermogravimetry TG
Thermobalance
Mass
mass vs temp 2
Derivative Thermogravimetry
DTG
dm/dt
dm/dt vs temp 3
Diff.Thermal Analysis
DTA
DTA Appts ∆T
∆T vs temp 4
Diff.Scanning Calorimetry
DSC
Calorimeter
dH.dt
dH/dt vs temp 5
Thermometric Titrimetry
……..
Temp.
Temp vs titrant volume 6
Dynamic Reflectance Spectroscopy
DRS
Spectrophotometer
Reflectance
%refle.and temp.

6. 7
Evolved gas detection
EGD
Thermal conductivity cell
T.C.
T.C. vs temp 8
Dialotometry
TMA
Dialatometer
Vol.of Length
Vol or length vs temp 9
Electrical conductivity EC
Electrometer or Bridget
Current or resistance
I or R vs temp 10
Emanation Thermal Analysis
ETA
ETA appts.
Radioactivity
E vs temp
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no

7. Thermal Analysis Instrument Manufacturers
Perkin Elmer Thermal Analysis Systems
TA Instruments
Mettler Toledo Thermal Analysis Systems
Rheometric Scientific
Haake
NETZSCH Instruments
SETARAM Instruments
Instrument Specialists, Inc.
Ref-by google search thermal method instrument

8. Thermogravimetry:
It is a technique whereby the weight of the substance, in an environment heated or cooled at a controlled rate, is recorded as a function of time or temperature.
Ref-Skoog, Douglas A., F. James Holler and Timothy Nieman (1998). Principles of Instrumental Analysis (5 ed.). New York. pp. 

9. Types of thermogravimetry:
1. Static thermogravimetry
2. Quasistatic thermogravimetry
3.Dynamic thermogravimetry
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no

10. Instrumentation: TGA Ref-Google image search BALANCE CONTROLLER
TEMPERATURE PROGRAMMER
BALANCE
CONTROLLER
POWER
FURNACE TEMP.
SAMPLE TEMP.
WEIGHT
INLET
Ref-Google image search

11. 1.Balance: Requirements: Accurate, sensitive, reproducible
Adequate range of automatic weight adjustment.
High degree of mechanical & electronic stability.
Rapid response to weight changes.
Should be unaffected by vibrations, simple to operate & versatile.
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no 2.705

12. Types of balances: 1.Deflection balance 2.Null point balance
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no

13. Types of deflection balance:
1.Beam type
2.Helical or spring type
3.Cantilever type
4.Torsion type
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no

14. Types of Deflection Balance: Fig: Deflection balance

15. Null-Point Balance:
Fig: Null-Point Balance

16. 2. Sample Holders: Types: 1.Shallow Pans 2.Deep Crucibles
3.Loosely Covered Crucibles
4.Retort Cups
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no

17. 3.The Furnace: For 1100ºC – Nichrome is used
1100 to 1500ºC. – Platinum or an alloy of platinum and rhodium
Above 1750ºC – tungsten or molybdenum
Nitrogen or argon are usually used to purge the furnace & prevent oxidation of sample.

18. 4. Temperature measurement:
Fig: Position of a Thermocouple in a Thermobalance

19. 5. Recorder: Time base potentiometric strip chart recorder
X Y recorder

20. 6.Thermobalance:
1)Continuously the weight changes of the sample as a function of temperature & time.
2) The temperature recorded to an accuracy of better than
±1%.
3) Temperature should, ideally, be the sample Temperature.
4) No chemical attack of volatile products on the apparatus.
5) The balance is protected from furnace.
6) The weight loss should be recorded to an accuracy of ±1%.
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no

21. TGA Applications: Inorganics
Hydrates decomposition, drying phenomena
Carbonates and other salts decomposition
Kinetics and mechanisms of oxidation, and other solid-gas reactions
Analysis of magnetic materials
Automatic TG analysis
Evaluation of TG pptet.
Test purity
Curie point determination
Ref-M C Ramos-Sanchez, F J Rey, M L Rodríguez, F J Martin-Gil, J Martin-Gil, "DTG and DTA studies on typical sugars", , 134: 55-60

22. TGA Applications: Organics
Identification of polymers and pharmaceutical agents
Thermal stability of synthetic and natural polymers and other organics
Analysis of polymer-matrix composites
Kinetics and mechanism of solid organics – gas reactions
Residual solvent determinations
Building material
Glass technology
Ref-M C Ramos-Sanchez, F J Rey, M L Rodríguez, F J Martin-Gil, J Martin-Gil, "DTG and DTA studies on typical sugars", , 134: 55-60

23. DTA:
DTA measures temperature difference between a sample and an inert reference (usually Al2O3) while heat flow to the reference and the sample remains the same
Ref-M C Ramos-Sanchez, F J Rey, M L Rodríguez, F J Martin-Gil, J Martin-Gil, "DTG and DTA studies on typical sugars", , 134: 55-60

24. Differential Thermal Analysis (DTA)
Ref-Mansfield, E.; Kar, A.; Quinn, T. P.; Hooker, S. A. (2010). ". Analytical Chemistry 82 .

25. Principle:
The principle of method consists of measuring the change in temperature associated with physical or chemical changes during the gradual heating of the substance.
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no

26. Differential Thermal Analysis
Advantages:
Instruments can be used at very high temperatures
Instruments are highly sensitive
Characteristic transition or reaction temperatures can be accurately determined
Disadvantages:
Uncertainty of heats of fusion, transition, or reaction estimations is 20-50%.
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no

27. Applications – Physical chemistry Analytical chemistry Quality control
Inorganic chemistry
Organic chemistry
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no

28. Differential Scanning Calorimetry (DSC)
4/26/2017
Differential Scanning Calorimetry (DSC)
Differential Scanning Calorimetry technique is a thermal technique in which the difference in the amount of heat required to increase the temperature of a sample & reference is measured as a function of temperature.
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no

29. Differential Scanning Calorimetry (DSC)
DSC measures differences in the amount of heat required to increase the temperature of a sample and a reference as a function of temperature

30. Differential Scanning Calorimeter

31. Differential Scanning Calorimeter Perkin Elmer DSC 7
Platinum sensors
Sample heater
Reference heater
Temperature range 110 – 1000 K
Heating rate 0.1 – 500 K/min (normally 0.5 – 50 K/min)
Noise ± 4 mW
Sample volume up to 75 mm3

32. Applications- Physical chemistry Analytical chemistry Quality control
Inorganic chemistry
Organic chemistry
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no

33. DSC in Polymer Analysis
Main transitions which can be studied by DSC:
Melting
Freezing
Glass transition

34. Difference Between: TGA DTA DSC Measures thermo-chemical effect.
Measures thermo-physical, thermo-chemical effect.
Measures thermo-physical, chemical effect with more sensitivity.
Provide range: Thermal Chemical stability of materials.
Provide range: Thermal, Physical and Chemical stability of materials.
Provide range: Thermal, Physical and Chemical stability and also transition time. E.g. Curie Temperature
Contains: Thermobalance.
Contains: Thermocouple for measuring ∆T.
Contains: Secondary heater for measure ∆H.

35. Thermo mechanical analysis:
Thermo mechanical analysis (TMA) is the technique in which a physical dimensions of a material is monitored as a function of temperature. With the other methods a thermocouple is used to monitor the temperature of the sample in an oven through which a purge gas flow.
Ref- introduction to thermal method by brown m.e. p.no-149

36. Thermo mechanical Analysis: Instrumentation
Consist of
Transducer(Linear Variable Displacement Transducer)
Probe (made up of quartz glass)
Thermocouple
Furnace
Ref-

37. Principle-
Measurement of effect of heat on mechanical property of sample eg. Expansion,Compression,Penetration and Extension.
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no 2.754

38. Applications- Polymer study Quality control
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no 2.754

39. Dielectric thermal analysis:
Dielectric thermal analysis (DETA) or Dielectric Analysis (DEA), is a material science technique similar to dynamic mechanical analysis except that an oscillating electrical field is used instead of a mechanical force.
Ref- vogel textbook of chemical analysis p.no

40. Dielectric thermal analysis: Principle
In a typical test, the sample is placed in contact with two electrodes(the dielectric sensor) and a sinusoidal voltage (the excitation) is applied to one electrode. The resulting sinusoidal current (the response) is measured at the second electrode. The response signal is attenuated in amplitude and shifted in phase in relation to the mobility of the ions and the alignment of the dipoles.
Ref- vogel textbook of chemical analysis p.no

41. Evolved gas analysis:
Evolved gas analysis (EGA) is a method used to study the gas evolved from a heated sample that undergoes decomposition or desorption.
It is possible to detect which gas is evolved using (EGD) Evolved gas detection..

42. Thermometric titrations:
Definition: A Titration in which the temperature of the titrant is monitored as a function of added titrant volume is a thermometric titration.
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no 2.739

43. Principle:
Thermometric Titrations is based on the change in temperature with theaddition of titrant & determine the end point from a plot of temperature vs. volume of titrant. In thermometric titration change in temperature occurs only when titration is in progress & sample reactant is present.
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no 2.739

44. Theory-
A titration reaction follow chemical equation aaaaaaaaaaaaaaaaaaaaaaaaa In this method there should be change in free energy at end point.
A(sample)+B(titrant)C(product)+heat
∆H=∆G+T∆S
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no 2.739

45. Instrumentation: It consist of
Delivery pump fig: thermometric titration assembly
Adiabatic cell (Dewar cell)
Calibration unit
Temperature sensing system
Amplification & Recording

46. 4/26/2017
Enthalpimetry:
Quantitative analysis of a sample can be sometimes be performed by measurement of the change in enthalpy that is associated with the addition of excess of a chemical reactant to the sample.
When a chemical reaction takes place heat is liberated or absorbed. This is known as heat of reaction or enthalpy.
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no 2.759

47. Methods: 1.Direct injection enthalpimetric titration (DIE):
In this technique in which a single portion of an excess of one chemical reactant is added to a fixed volume of a sample that contains other reactant.
2. Continuous flow enthalpimetry:
Similar to DIE except that an excess of one reactant is continuously to flowing stream of sample added.
Ref-Instrumental methods of chemical analysis by Gurdeep Chatwal and shyam anand, himalaya publication thermal method,p no 2.759

48. Thank You. . .