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  • Observation of intensity dependent phase-separation in photoreactive monomer–nanoparticle formulations under non-uniform visible light irradiation
Title: Observation of intensity dependent phase-separation in photoreactive monomer–nanoparticle formulations under non-uniform visible light irradiation
We report observations of photopolymerization driven phase-separation in a mixture of a photo-reactive monomer and inorganic nanoparticles. The mixture is irradiated with visible light possessing a periodic intensity profile that elicits photopolymerization along the depth of the mixture, establishing a competition between photo-crosslinking and thermodynamically favorable phase-separating behavior inherent to the system. In situ Raman spectroscopy was used to monitor the polymerization reaction and morphology evolution, and reveals a key correlation between irradiation intensity and composite morphology extending the entire depth of the mixture, i.e. unhindered phase-separation at low irradiation intensity and arrested phase-separation at high irradiation intensity. 3D Raman volume mapping and energy dispersive X-ray mapping confirm that the intensity-dependent irradiation process dictates the extent of phase separation, enabling single-parameter control over phase evolution and subsequent composite morphology. These observations can potentially enable a single-step route to develop polymer–inorganic composite materials with tunable morphologies.  more » « less
Award ID(s):
1751621
PAR ID:
10171180
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Soft Matter
ISSN:
1744-683X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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