Calorimetry

Scanning probe microscopy in general offers no way of identifying the chemical constituents present in different parts of the image. However, we have combined scanning thermal microscopy with M-T DSC (modulated-temperature differential scanning calorimetry, a powerful new method for the thermal analysis of bulk samples): the required temperature ramp is applied locally by the thermal probe itself, used simultaneously as a heater.

The result is known as Localised Calorimetric Analysis, by which chosen regions of the SThM or AFM image are subjected to localised thermal analysis. This is able to distinguish reversible processes (such as amorphous-to-glass transitions in a polymer) from chemical reactions, recrystallisations, and other irreversible processes. Thus, chemical fingerprinting of regions of a few cubic microns in volume is possible.

View Image - Variations of crystallinity in branched polyethylenes

Abstracts

• (Topical review): Micro-thermal analysis: techniques and applications
  http://www.lancs.ac.uk/depts/physics/research/condmatt/micro/jphysd-mta01.htm
  
  
• Micro-Thermal Analysis: scanning thermal microscopy and localised thermal analysis
  http://www.lancs.ac.uk/depts/physics/research/condmatt/micro/intjpharm99.htm
  
  
• An integrated SThM / thermal analysis technique with applications in polymer science
  http://www.lancs.ac.uk/depts/physics/research/epsrc/gr-l-02067.htm
  
  
• Calorimetric analysis with scanning microscopy
  http://www.lancs.ac.uk/depts/physics/research/condmatt/micro/vision96.htm
  
  
• Scanning thermal microscopy: sub-surface imaging, thermal mapping of polymer blends, localised calorimetry
  http://www.lancs.ac.uk/depts/physics/research/condmatt/micro/jvacsci96.htm
  
  
• Interfaces in polymeric systems as studied by C.A.S.M. - a new combination of Calorimetric Analysis with Scanning Microscopy
  http://www.lancs.ac.uk/depts/physics/research/condmatt/micro/jadhesion98.htm
  
  
• Localised thermal analysis using a miniaturised resistive probe
  http://www.lancs.ac.uk/depts/physics/research/condmatt/micro/revsciinst96.htm
  
  
• Highly localised characterisation of polymers
  http://www.lancs.ac.uk/depts/physics/research/condmatt/micro/jvacsci00.htm