Differential Scanning Calorimetry

Shen Haiyan

New testing equipment - DSC (Differential Scanning Calorimetry) was put in use.

By investing in new DSC (differential scanning calorimeter) equipment, KRS can analyze and identify the properties of a variety of rubber raw materials and compounds (including unvulcanized rubber and vulcanizate).            

DSC is used to measure the temperature of physical transformation and chemical reaction, and to determine the enthalpy change involved in these processes. Information about the content and physical structure of the material can be obtained. For example, the analysis of glass transition provides information on the compatibility of polymer blends and the types of polymers and fillers used.  

In addition, crystallization and melting behavior of polymers and additives, as well as possible secondary vulcanization reaction or thermal stability can be studied. Moreover, these methods can characterize the effect of additives on melting point and glass transition.  

If liquid nitrogen is selected as the refrigeration medium, the working temperature range of DSC can be from - 180 ℃ to 700 ℃ (the working temperature range of DSC newly purchased by our company is - 85 ℃ to 600 ℃). A typical test usually starts at a low temperature and then heats the sample at a specific rate, usually set at 10 degrees per minute. Of course, samples can also be cooled rapidly (quenching cooling) according to specific analysis requirements. Generally speaking, the test is carried out in inert gas environment such as nitrogen environment, and can be switched to "normal" air environment according to special requirements.            

In addition to thermogravimetric analysis, the equipment can be used for in-depth and accurate detection of polymer structure and rubber compound properties, and can be used for raw material testing and finished product testing. DSC is mainly used to detect the following thermal effects:            

  • Melting point temperature and enthalpy (heat content)            

  • Crystallization temperature and enthalpy            

  • Glass transition temperature            

  • Crystallinity            

  • Reaction temperature and enthalpy            

  • Crosslinking reaction (vulcanization)            

  • Degree of vulcanization            

  • Specific heat capacity