Mass production of uniformly sized air-filled poly-lactic acid microcapsules made from microbubble templates
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Date
2019-01-16Author
Molino, Jay
Jojlova, Svetlana
Hirofumi Daiguji and
Takemura, Fumio
Metadata
Show full item recordAbstract
Hollow poly(Lactic Acid) (PLA) microcapsules were fabricated
using the bubble template method. In this method, microbubbles nucleated
inside droplets of a dichloromethane solution of PLA which were located in
a continuous phase of poly(vinyl alcohol). PLA-covered microbubbles
formed when PLA adsorbed to the bubble surface by physisorption. Then,
the coated microbubbles were spontaneously released from the droplet´s
interior into the continuous phase. To increase the production yield of
hollow microcapsules in this method, ultrasound was applied to enhance
bubble nucleation inside the droplets. Thus to attain uniform hollow PLA
microcapsules, the optimum PLA concentration with ultrasound was 30 g
L
−1
, which is higher than that without ultrasound (2 g L−1
). At the optimum
concentration, the average radius was 0.54 µm, with a polydispersity index
of 21.2%. It was found that the equilibrium size of the microbubble
template radius was the same with and without ultrasound. The production
yield had a tenfold increase when ultrasound was employed.