Determination of the coalescence temperature of latexes by Environmental Scanning Electron Microscopy
CIC nanoGUNE Seminars
- Speaker
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Edurne González, Polymat UPV, Donostia, Spain
- When
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2012/05/21
13:00 - Place
- nanoGUNE seminar room, Tolosa Hiribidea 76, Donostia - San Sebastian
- Add to calendar
-
iCal
The final application of most of waterborne polymeric dispersions is in the
form of film (i.e. as paint or adhesive). Film formation process is the
transformation of the polymeric dispersion into a coherent film and this
process is usually divided in three stages: (i) evaporation of water and
particle packing, (ii) deformation of particles and (iii) coalescence and
interdiffusion between particles. In collaboration with EM laboratory of
nanoGUNE we have developed a new methodology for quantitative characterisation
of the coalescence process of waterborne polymer dispersion (latex) particles
by Environmental Scanning Electron Microscopy (ESEM). Experimental setup has
been developed providing reproducible latex monolayer deposition, optimized
contrast of latex particles and reliable readout of the sample temperature.
The quantification of the coalescence process has been performed by image
processing based on evaluation of the image autocorrelation function. As a
proof of concept the coalescence of two latexes (poly(methyl
methacrylate/butyl acrylate)) with known different glass transition
temperatures has been measured. It has been shown that a reproducibility of
the measurement of the coalescence temperature better than 1.5°C can be
obtained.