Standard Thermogravimetric Analyzer

What is the Standard Thermogravimetric Analyzer?

A standard thermogravimetric analyzer combines a microbalance with a furnace up to 1000 degrees Celsius and programmable purge gas, giving mass loss curves for polymers, pharmaceuticals and general materials. It is the standard configuration for composition and thermal stability testing.

Overview

The instrument uses a top-loading or hanging microbalance with a resolution of 0.1 microgram and a capacity of about 1 gram, set in a temperature-controlled enclosure to reduce drift. The furnace covers ambient to 1000 degrees Celsius at heating rates from 0.1 to 50 degrees Celsius per minute, and the sample thermocouple is positioned a fraction of a millimetre below the crucible for accurate temperature reporting. Inert and reactive gases are switched by a mass flow controller, including automatic switching during a run to compare decomposition in nitrogen and air. Curves are displayed as mass percentage, mass, derivative and temperature, and the software reports step onsets, peak maxima and residue values. Crucibles in alumina, platinum or quartz are interchangeable, and a sample robot holding 30 or more crucibles provides unattended sequences. Typical repeatability is 0.05 to 0.1 percent by mass for well-behaved samples.

How does it work?

A sensitive balance holds the sample in a furnace whose temperature follows a program, usually from ambient to 1000 or 1600 degrees Celsius, at rates of 1 to 50 degrees Celsius per minute. The balance beam is purged to protect it from heat and condensable vapours, and a separate purge gas flows over the sample to set the atmosphere: inert nitrogen or argon for decomposition studies, air or oxygen for oxidative tests, or a reactant gas for specific reactions. The instrument records mass against temperature or time, and the derivative curve is used to locate the onset of each mass loss step. Buoyancy and gas-flow effects are corrected with a blank run. Calibration uses certified mass standards and Curie-point or melting-point references for temperature. Typical balance resolution is 0.1 microgram with a sample of a few milligrams, giving a measurement precision of about 0.1 percent by mass.

What are the key features?

• Microbalance with 0.1 µg resolution and 1 g capacity
• Furnace from ambient to 1000 °C at 0.1–50 °C/min
• Mass flow controlled inert and reactive gas switching
• Derivative curve evaluation of step onsets and residues
• Interchangeable alumina, platinum and quartz crucibles
• Autosampler for 30 or more crucibles with unattended operation

What are the technical specifications?

A typical standard thermogravimetric analyzer configuration offers temperature range of Ambient–1000 °C, balance resolution of 0.1 µg, balance capacity of 1 g, heating rate of 0.1–50 °C/min, temperature accuracy of ±1 °C (Curie point) and weighing precision of ±0.1% by mass. Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.

Which applications is it used for?

The Standard Thermogravimetric Analyzer is used in polymer filler and ash content, pharmaceutical hydrate and solvate studies, rubber and composite formulation checks, food moisture and volatiles and general thermal stability screening. Across the wider TGA class, laboratories also deploy it for polymer composition and filler content, pharmaceutical hydrate and solvate studies and coal, biomass and fuel analysis.

Which standards and certifications apply?

Relevant standards and methods include ASTM E1131, ASTM E2550, ASTM D3850, ISO 11358-1, ISO 11358-2 and USP <891>. Certification candidates for this model are CE, IEC 61010-1 safety and ISO 9001 manufacturing; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Choose crucibles that do not react with the sample or the gas: alumina for most work, platinum for oxidative tests or when high thermal conductivity helps, and quartz or ceramic for high-temperature inert runs. Keep sample mass between 5 and 20 milligrams so the gas flow is not restricted and heat transfer is even. Run a blank to correct buoyancy and purge effects before starting a series, and verify mass with a calibration weight periodically. Condensable decomposition products must be kept out of the balance chamber, usually by a trap or by a higher balance purge flow. Temperature calibration should be repeated after a furnace or sensor change, and every run should record crucible type, gas, flow rate, heating rate and sample mass so results can be reproduced. Compliance laboratories should keep the raw curves, not just the calculated numbers.

How do I select the right Standard Thermogravimetric Analyzer?

Choose the standard configuration when decomposition below 1000 degrees Celsius and microgram balance resolution cover your samples, which is true for most polymers, foods and pharmaceuticals. For ceramics, slags or metal oxides, a high-temperature furnace is needed. In an RFQ, specify crucible types, gas control, autosampler and calibration references.

How does it compare with other TGA variants?

Decide the maximum temperature you need, because it drives the furnace design: 1000 degrees Celsius covers most polymers and pharmaceuticals, 1500 to 1600 degrees Celsius is needed for ceramics, metal oxides and slags. Then define the atmosphere and whether evolved gases must be identified, which determines whether an FTIR or mass spectrometer coupling is required. Consider the balance resolution you need: routine filler and moisture determinations work with microgram resolution, while thin films or residues need sub-microgram sensitivity. Automatic sample changers pay back quickly in quality control laboratories that run many samples. Check baseline stability, buoyancy correction, purge gas control, crucible material and the maximum heating rate, and confirm that the instrument's calibration procedures match the method you must follow, such as ASTM E1131 or ISO 11358.