Differential Scanning Calorimetry Test of Polymers

Spectro Analytical Labs is fully equipped to provide ‘Differential Scanning Calorimeter (DSC) thermal analyses’ for a wide range of products like polymers, plastics, inorganic chemicals, ceramics etc. The services provided by Spectro include research and development (R&D) work, quality control work, process and product development, and various other applications. DSC thermal analyses cater to a wide range of industries like Polymers & Plastics, Ceramics, inorganic Chemicals, biological products, pharmaceuticals etc. Spectro has state-of-the-art DSC equipment to provide accurate and reliable results, and has been able to serve its customers satisfactorily for quite a while.

Brief History of DSC: The technique was developed by E.S. Watson and M.J. O’Neill in 1962, and introduced commercially for the first time in 1963. Shortly later, its applications were explored into other fields like biochemistry. The term DSC was coined to describe the fact that this instrument measures energy directly and allows precise measurements of heat capacity.

‘Calorimetry’ is the science of measuring the heat of chemical reactions or physical changes, and the measurement is achieved using a Calorimeter. A Differential Scanning Calorimeter (DSC) measures the heat energy necessary to maintain a nearly-zero temperature difference between a test substance and an inert reference material, while the two substances are subjected to an identical temperature program. DSC can quantitatively measure various thermal transition processes that take place in a substance during heating. The result of a DSC experiment is a curve of heat flux versus temperature or time. The nature of the curve varies with the type of heating process, viz. Exothermic process in which heat is released during the experiment, and Endothermic process in which heat is absorbed during the experiment.

Differential Scanning Calorimetry can be used to measure a number of characteristic properties of a sample, and some of the important ones are:

  • Glass Transition Temperature
  • Melting & Boiling points
  • Crystallization time and Temperature
  • Heats of fusion & reactions, Specific heats
  • Oxidative & Thermal Stability
  • Gelation
  • Reaction Kinetics
  • Material Identification

Thermal analysis of a polymer allows an insight into the phases of the polymer matrix. For PVC the gelation can also be measured. ‘Oxidation Induction Time’ measures the amount of time a polymer needs to oxidize at an elevated temperature, which gives an insight into the concentration of antioxidants remaining in the polymer matrix; the less time required the smaller the concentration of antioxidants present. The crystallinity is the measure of the amount of heat required to melt the crystalline part of the polymer matrix (the heat of fusion). The higher the percentage of crystalline material in the polymer matrix, the more degradation has occurred. Melt temperature allows investigation of the polymer’s thermal stability; the higher the melt temperature the more thermally stable the polymer. Gelation is a measurement to examine the degree of fusion in the rigid polymer. Gelation measures the amount of entanglement in the PVC resin. This begins with the production of the polymer, but also continues as the PVC ages.

In comparison with other techniques of Calorimetry, DSC offers a number of distinct advantages like it requires a very small quantity of test substance. It is also very fast and easy to use. It helps in monitoring a large number physical and chemical properties of substances. This technique is used by a number of industries like polymers, pharmaceuticals, food processing, biological substances, organic and inorganic chemicals, ceramics etc

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: