Study on concentration distribution in phase separation photo-curing coatings.

Using the common focus Raman spectroscopy, the scientists directly measured the distribution of local components in phase-separated photo-cured films.
to prevent light from scattering at the phase interface, they developed a new technique to match the reflection index in the curing film with a monosome instead of a solvent. The results show that the concentration distribution of the polymer is uniform in the solvent-free monomer/trigger binary solution, and when the solvent-based film is thermodynamically unstable and ultraviolet radiation is carried out on the top surface, the spatial distribution of the polymer is uneven .
a double-layer structure
in the 31st case, the membrane exhibits a double-layer structure in which the polymer concentration is almost uniform near the top surface and the concentration gradient is formed near the bottom surface. The top thickness with uniform concentration distribution increases with the increase of UV intensity.
results show that the propagation of the reaction frontier and the optical drive transmission of the solvent to the base coating play a key role in the formation of uneven concentration distribution in the photo-cured solution coating.
the study has been published in the Journal of Coating Technology and Research, volume 16, 1629-1636.
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