Polymer stabilized Monodispersed Liquid Crystal Droplets: Microfluidics Generation and Optical Analysis

• Authors: D. E. Lucchetta , F. Simoni , P. Pagliusi , G. Cipparrone
• Languages of publication: EN

Abstracts

EN

Liquid crystal droplets are widely used in optics
and photonics applications. They can act as simple
resonators or be arranged in interconnected periodic configurations when their external dimension are similar. In
this work we optically analyze and describe the microfluidic
generation of liquid crystal droplets in a thermally stabilized
environment, namely water, which enables a narrow
droplets diameter distribution.We demonstrate a fine
control of the droplet dimensions in both nematic and
isotropic phases by controlling the ratio between liquid
crystal andwater flows. Droplets generated in the isotropic
phase show a complex internal structure which reflects
their high degree of internal disorder. Moreover, the internal
configuration of the droplets also depends on the
purity degree of the water in which they grow. In order to
investigate their size distribution and their internal structure,
a small amount of photo-polymerizable agent (NOA61
optical glue)was added to the liquid crystal to stabilize the
droplets structure and to avoid their coalescence. Acting
this way, polymer stabilized liquid crystal droplets were
created after light induced polymerization, which are stable
even after water evaporation. The polarized microscope
analysis shows that the bipolar or radial order of the
liquid crystal is still preserved inside the droplets depending
on the water purity. Moreover an improved size uniformity
is reported.

Keywords

EN

Polymers; Liquid Crystals; Microfluidics; Microdroplets

• Publisher: De Gruyter Open
• Journal: Optical Data Processing and Storage
• Year: 2014
• Volume: 1
• Issue: 1

Dates

received

17 - 11 - 2014

accepted

2 - 3 - 2015

online

25 - 5 - 2015

Contributors

author

D. E. Lucchetta

• Dipartimento SIMAU, Università Politecnica delle
  Marche, Via Brecce Bianche, 60131 Ancona, Italy

author

F. Simoni

• Dipartimento SIMAU, Università Politecnica delle
  Marche, Via Brecce Bianche, 60131 Ancona, Italy

author

P. Pagliusi

• Dipartimento di Fisica, Università
  della Calabria, Via P.Bucci, Cubo 31 C, 87036 Arcavacata di Rende,
  Cosenza

author

G. Cipparrone

• Dipartimento di Fisica, Università
  della Calabria, Via P.Bucci, Cubo 31 C, 87036 Arcavacata di Rende,
  Cosenza

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Identifiers

DOI

10.1515/odps-2015-0001