Thermal analysis is the broad category of at least 20 techniques that measure some fundamental property of matter as a result of adding heat. For example, dilatometry measures volume changes upon heating, thermomechanical analysis quantifies the change in dimension of a sample as a function of temperature, and thermo-optical analysis detects changes in optical properties on heating or cooling. This discussion applies mostly to two techniques, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), although many of the ideas presented here apply to other types of thermal analysis. DSC and the related micro-DSC measure the amount of heat required to change the temperature of a sample. DSC is most often used with materials that undergo phase changes. Homogeneous or nonhomogeneous materials that melt or freeze, or that undergo transformation from one solid form to another, are excellent candidates for DSC. Notable examples include the glass transition temperature of polymers and the interconversion of crystalline polymorphs in the pharmaceutical industry. Approximately 60 percent of thermal analyses involve DSC. TGA is often used to quantify residual solvent or moisture content of a sample (for example, in foods and pharmaceuticals). A related technique, evolved gas analysis, analyzes gas decomposition products.
The types of analyses our readers are performing or planning to perform in their labs:
| Currently Performing | Planning to Perfom | |
| Dielectric Thermal Analysis | 3% | 5% |
| Differential Thermal Analysis | 9% | 6% |
| Differential Scanning Calorimetry | 18% | 5% |
| Dilatometry | 1% | 1% |
| Dynamic Mechanical Analysis | 3% | 3% |
| Evolved Gas Analysis | 5% | 2% |
| Thermogravimetric Analysis | 13% | 7% |
| Thermomechanical Analysis | 5% | 1% |
| Thermo-optical Analysis | 4% | 1% |
| Other | 6% | 2% |
Our readers work with the following materials which require them to perform thermal analysis:
| Organics such as lubricants, pharmaceuticals, paints, adhesives, etc. | 29% |
| Polymers | 26% |
| Minerals, inorganic chemicals, and other inorganics | 19% |
| Metals / alloys | 10% |
| Other | 10% |
| Ceramic / glass / building materials | 5% |
The physical states of the materials our readers analyze:
| Powder | 28% |
| Liquid | 20% |
| Pellet | 13% |
| Thin Film | 12% |
| Fiber | 10% |
| Paste | 8% |
| Gel | 6% |
| Foam | 4% |
The type of information our readers require from their thermal analyses:
| Quantitative | 24% |
| Qualitative | 9% |
| A mixture of both | 67% |
Simultaneous Thermal Analysis (STA) combines the benefits of thermal analysis and differential scanning calorimetry (measurement of the energy flow to or from the sample, quantifying the changes as exothermic or endothermic) into a single experiment. Seven percent of the respondents are currently performing STA in their research and another 40 percent are planning to use STA within the next 12 months.
Survey respondents’ top ten factors/features they look for in a thermal analyzer:
| Important | |
| Reliability | 80% |
| Ease of use | 67% |
| Service and support | 58% |
| Low maintenance/easy to clean | 54% |
| Price | 54% |
| Safety | 51% |
| Warranty | 49% |
| Low operating cost/ cost of ownership | 48% |
| Ease of installation | 39% |
| Versatility | 39% |
For more information on thermal analyzers, including useful articles and a list of manufacturers, visit www.labmanager.com/thermal-analyzers
