Enhanced Dielectric Properties of P(VDF-TrFE-CTFE)/PMMA Composites with MWCNTs@SiO₂ Core-Shell Fillers.

Area of Science:

• Materials Science
• Polymer Science
• Nanotechnology

Background:

• Dielectric materials are crucial for electrowetting-on-dielectric (EWOD) device performance.
• Enhancing dielectric properties of polymers is key to advancing EWOD technology.

Purpose of the Study:

• To fabricate and characterize MWCNTs@SiO2 core-shell structured fillers.
• To incorporate these fillers into a polymer matrix for EWOD applications.
• To evaluate the impact of core-shell fillers on dielectric properties and EWOD performance.

Main Methods:

• Fabrication of MWCNTs@SiO2 core-shell fillers via SiO2 coating on MWCNTs.
• Incorporation of fillers into a P(VDF-TrFE-CTFE)/PMMA polymer matrix.
• Characterization of dielectric properties (dielectric constant, dielectric loss, breakdown strength) and EWOD performance (contact angle modulation).

Main Results:

• Composite films with 4 wt% MWCNTs@SiO2 fillers achieved a dielectric constant of 25.4 (108.2% enhancement) at 100 Hz with low dielectric loss (0.05).
• The SiO2 shell improved electric field distribution and breakdown strength.
• A contact angle modulation range of 38.3° was achieved (151.97% enhancement) below 50 V DC.

Conclusions:

• MWCNTs@SiO2 core-shell fillers significantly enhance dielectric properties and EWOD performance.
• This core-shell structure offers a promising strategy for developing advanced dielectric materials for EWOD devices.