Simultaneous DSC-TGA Analyzer for Polymer Analysis

What is the Simultaneous DSC-TGA Analyzer for Polymer Analysis?

A simultaneous DSC-TGA analyzer measures heat flow and mass change on the same polymer sample in one experiment. It is the right instrument when melting, curing or decomposition events overlap, because mass loss identifies which thermal event involves volatilisation or degradation.

Overview

A simultaneous analyzer places the sample in a combined holder that includes both a differential thermocouple or heat-flux plate for calorimetry and a sensitive balance for mass measurement. Both signals are recorded against the same temperature programme, so an endotherm accompanied by mass loss is a vaporisation or decomposition event, whereas an endotherm with no mass change is a melt. A curing exotherm without mass change shows crosslinking, while the same exotherm with mass loss suggests a condensation cure releasing volatiles. Typical balance resolution is 0.1 to 1 µg with sample sizes of 5 to 20 mg, and the cells usually accept inert, oxidising and humidified atmospheres. Simultaneous measurement is less sensitive than a dedicated DSC for weak transitions, so it is used where mass information adds diagnostic value.

How does it work?

A DSC cell holds the sample and an empty reference pan on a common sensor plate inside a furnace programmed through a controlled temperature ramp. The instrument records the differential heat flow needed to keep sample and reference at the same temperature, in milliwatts, against the furnace temperature or time. Endothermic events such as melting and volatilisation appear as peaks, and exothermic events such as crystallisation and curing appear as positive deviations. Heat-flux cells measure the temperature difference across a thermoelectric disc, while power-compensation cells heat the two holders separately and record the power difference directly. Calibration uses the melting point and enthalpy of indium, and often zinc and tin, with a sapphire disc for specific-heat calibration. Purge gas, sample mass, pan type and heating rate all influence peak shape and the temperatures reported for polymers.

What are the key features?

• Simultaneous heat flow and mass-change signals
• Balance resolution down to 0.1 µg
• Inert, oxidising and humidified atmospheres
• Distinguishes melting from decomposition events
• Temperature-programmed purge gas switching
• Crucibles in alumina, platinum and aluminium

What are the technical specifications?

A typical simultaneous dsc-tga analyzer for polymer analysis configuration offers temperature range of Ambient to 1500 °C, heating rate of 0.1–50 °C/min, balance resolution of 0.1 µg, weighing accuracy of ±0.5%, typical sample mass of 5–20 mg and calorimetric accuracy of ±2% (indium). 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 Simultaneous DSC-TGA Analyzer for Polymer Analysis is used in thermoset cure studies with volatile release, filler and carbon black content determination, decomposition onset of flame-retarded polymers, moisture and solvent content of compounds and thermal stability comparison of grades. Across the wider DSC class, laboratories also deploy it for glass transition and melting point determination of polymers, degree of crystallinity and crystallisation kinetics and cure monitoring of thermosetting resins.

Which standards and certifications apply?

Relevant standards and methods include ISO 11357-1, ISO 11357-2, ISO 11357-3, ASTM D3418, ASTM E1356, ASTM D3895 and IEC 61010-1. Certification candidates for this model are CE 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.

Calibrate temperature and enthalpy with indium before each campaign, or at least monthly, and check the baseline with an empty pair of pans. Seal volatile or moisture-sensitive samples in hermetic pans and work with a dry inert purge gas to suppress oxidation and ice formation. Sample mass of 5 to 10 mg in a standard pan usually balances resolution and thermal lag; heavy fillers may need more mass and slower heating rates. Keep the cell clean, record cooling conditions together with heating data because thermal history controls crystallinity, and store the raw curves so that re-analysis with different limits remains possible.

How do I select the right Simultaneous DSC-TGA Analyzer for Polymer Analysis?

Choose a simultaneous analyzer when a DSC curve alone is ambiguous, for example when a melt overlaps with decomposition or when a curing exotherm may also release volatiles. Specify the maximum temperature from the filler or ash content work rather than from polymer melting, since muffle-furnace comparisons often require 800 to 1000 °C. Confirm the balance resolution for the smallest mass change you must quantify.

How does it compare with other DSC variants?

The first decision is cell type. Heat-flux cells cope with larger samples and give robust results in routine polymer QC; power-compensation cells offer faster response and better resolution of weak transitions, which helps in research on blends and thin films. Then fix the temperature range: below-ambient capability needs a liquid nitrogen or mechanical cooling accessory, while engineering polymers need a cell rated to at least 600 °C. Sensitivity matters when a weak glass transition in a highly filled compound must be detected, and an autosampler matters above roughly twenty samples per day. Where decomposition begins close to a melting or curing event, choose a simultaneous DSC-TGA instrument so mass loss and heat flow are recorded on the same sample.