To solve the fabrication problems of flexible microfibers with high aspect ratio
we proposed a method to recover the collapsed microfibers and improve the stability of the recovered microfibers by reducing the surface energy of collapsed microfibers with fluroresin treatment. By this way
the large-scale fabrication of high aspect ratio microfibers with low cost and high stability can be realized. Through the analysis on the mechanical model
the critical conditions of ground collapse and the lateral collapse were obtained. In addition
the relationship of the two was investigated in detail. Under the unsteady state
the microfibers would tend to ground collapse rather than lateral collapse. The experimental results showed that the collapsed microfibers treated by low-surface-energy fluroresin will spring back to their original upright position(high aspect ratio 10)by the treatment of ultrasonic-assisted vibration.
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