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Temperature-Controlled Assembly and Characterization of a Droplet Interface Bilayer
Published on: April 19, 2021
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Temperature Mediated Morphological Transition during Drying of Spray Colloidal Droplets
Priyanka Biswas1, D Sen1, S Mazumder1
1Homi Bhabha National Institute , Mumbai 400094, India.
Langmuir : the ACS Journal of Surfaces and Colloids
|February 23, 2016
Summary
Drying temperature controls microcapsule morphology, transforming spheres to toroids. This temperature-dependent transformation of colloidal spray droplets into microgranules offers tunable nanoparticle structures.
Area of Science:
- Materials Science
- Chemical Engineering
- Colloid Science
Background:
- Understanding the transformation of evaporative colloidal spray droplets into microgranules is key for materials science and technology.
- Microcapsule morphology and size distribution are critical parameters influencing their performance in various applications.
Purpose of the Study:
- To demonstrate that microcapsule morphology and size distribution can be controlled by adjusting drying temperature.
- To investigate the morphological transition from spherical to toroidal shapes with increasing temperature.
- To elucidate the mechanism behind this morphological transformation and its effect on capsule properties.
Main Methods:
- Quantification of capsule shape and size at four different drying temperatures.
- Utilizing scattering and imaging techniques to analyze capsule hollowness and buckling.
- Employing computer simulations to corroborate experimental observations.
Main Results:
- Morphology transitions gradually from sphere to toroid as drying temperature increases.
- Average volume-fraction of nanoparticles remains largely unaffected by temperature-induced morphological changes.
- Hollowness and buckling tendencies of the microcapsules are elucidated.
Conclusions:
- Drying temperature is a simple yet effective parameter for tuning microcapsule morphology.
- A plausible mechanism for the sphere-to-toroid morphological transformation has been proposed and validated.
- The findings provide insights into controlling nanoparticle assembly within microcapsules for tailored applications.
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