Simultaneous Thermogravimetry-Differential Thermal Analysis TG-DTA

Since TG and DTA were the two commonest techniques for many years and since DSC has taken over from DTA in recent times, and given their essentially complementary nature, it is not surprising that their combina- 

In one of the few reviews dedicated to STA the Paulik brothers claim to have been the first to build a true simultaneous TG-DTA, in 1955. Over many years they developed their instrument, the Derivatograph to incorporate dilatometry, and evolved gas analysis, and used it to pioneer the development of controlled rate methods. By modern standards, the instrument performance was pedestrian, and used samples of 

A different approach has been taken by TA Instruments, in using two horizontal balances. The balance arms, each with a thermocouple attached to a pan carrier, hold the sample and reference adjacent to each other in the furnace. Unusually, in this instrument there is no heat flow path between the sample and reference, other than through the surrounding atmosphere, which limits the quality of the DTA data. Mettler-Toledo now offer a technique in which a form of DTA is obtained by comparing the sample temperature with a calculated reference temperature profile. Modern TG-DTA instruments are capable in general of a TG resolution around 1 g, use samples typically from 5 to 100 mg, and can give sensitive and quantitative DTA performance when the head is of 

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