The thermo-microbalance, TG 209 F3 Tarsus®, represents a cost-effective overall concept, tailored not only to the quality assurance of polymers, but also to routine applications in the fields of organic, chemistry, pharmaceuticals, cosmetics and food.
This basic instrument for thermogravimetric measurements offers already a resolution of 0.1 µg. The TG 209 F3 Tarsus® operates between room temperature and 1000°C with freely selectable heating rates from 0.001 K/min up to 200 K/min. The accurate sample temperature is detected by a thermocouple in direct contact with the sample crucible. Through the reliable vertical construction with sample carrier lift, the thermo-balance as a top-loader, is easy and safe to use, with no hang-down wires or exposed fragile parts.
The calculated DTA-signal c-DTA® (option) not only is ideal for temperature calibration. During sample measurements it yields important information regarding endothermal processes (e.g. Vaporization with mass loss or melting without mass loss) as well as Exothermic reactions.
For the TG 209 F3 Tarsus® we offer an automatic sample changer (ASC) for to 20 samples also in different crucible types.
Micro-Furnace for Dynamics in Day-to-Day Lab Tasks
The low-volume furnace of the gas-tight NETZSCH TG 209 F3 Tarsus® consists of an SiO2-coated monolithic metallic heater with an integrated air cooler. Between room temperature and 1000°C, a heating rate of 200 K/min can be achieved for a high sample throughput. Safe handling is ensured by safety features. This includes purging of the balance chamber with protective gas
Detection of the Sample Temperature
The sample temperature is detected by a thermocouple in direct contact with the sample crucible. This ensures accurate reading of the sample temperature and makes it nearly independent from the atmosphere, gas flow or heating rate.
More Than Just a TGA! Monitoring Caloric Effects without Mass Loss
The calculated DTA signal, c-DTA®, is ideal for easy temperature calibration without the need of a magnet and disassembling of the instrument. It also yields information regarding endothermic and exothermic processes (e.g., melting without mass loss or evaporation with mass loss).
Auto-Cycle Evacuation – Fast Gas Exchange and Saving Purge Gas
The instrument’s three gas connections allow for fast gas exchange when changing the atmosphere (e.g., from inert to oxidizing). In addition to two purge gases, an inert gas is introduced into the balance for protection purposes. The time-controlled auto-cycle evacuation prior to measurement automatically evacuates and refills the system. It ensures less purging time before the measurement starts and therefore less gas consumption.
Automatic Sample Changer (ASC) – Makes Routine Work Easy
The ASC for up to 20 samples allows predefined methods to be included for each sample on the tray. Depending on the method, evaluation of the sample measurements can be carried out automatically. For quality control purposes, the temperature limits of earmarked effects can be set.
Principle of Operation
A thermobalance is used to measure themass change of a sample as a function oftemperature or time, under a defined andcontrolled environment with respect toheating rate, gas atmosphere, flow rate,crucible type, etc.
Various international standards describe thegeneral principles of thermogravimetry forpolymers (ISO 11358) or other specificapplications, such as compositional analysisfor rubber (ASTM D6370) and evaporationloss of lubricating oils (ASTM D6375).
Measurement Results
This TGA measurement shows thedecomposition of a black highdensity polyethylene (HDPE). In anitrogen atmosphere, there is onlya single mass-loss step detectedand it represents a nearly completedecomposition. The residual massof only 0.8% is evidently due tocarbon black. The corresponding 1stderivative of the TGA curve, DTGA,provides the decomposition rate.The DTGA peak temperature(478°C) is usually used as a characteristic value to specify the appropriate step.
The decomposition products of PEare wax-like. However, by speciallymodifying the exhaust of the TG209 F3 Tarsus® (optional), PE canalso be investigated on a routinebasis.
TGA features:
• Mass changes in % or mg
• Automatic evaluation of mass changing steps
• Determination of mass / temperature pair of variates
• Determination of the residual mass
• Extrapolated onset and endset
• Peak temperatures of the 1st and 2nd derivate of the mass changing curve
• Switch on/off function of buoyancy-correction
• c-DTA®for the calculated DTA signal with evaluation of characteristic temperatures and peak area (option)
• Super-Res for automatic rate controlled mass change and high resolution temperature programs (option)