12-15 July 2011
Saint George Hotel
Africa/Johannesburg timezone

Nanoscale manipulataion of lamellar copolymers using electric fields.

15 Jul 2011, 08:00
15m
Parthenon

Parthenon

Oral Presentation Track A - Condensed Matter Physics and Material Science CMPMS1

Speaker

Dr Simiso Mkhonta (University of Swaziland)

Description

Block copolymers can self-assemble into lamellar and cylindrical phases with a fundamental period of 10-100nm. These nanoscopic phases are a basis for a great range of applications in nanotechnology. We describe how electric fields can be utilized to tune the lamellar period of copolymers that consist of liquid-crystal sub-units. Copolymers that are swollen in liquid-crystals have anisotropic chains and liquid-crystals have a dielectric anisotropy. We evaluate the critical electric field required to tilt the liquid-crystal director relative to the lamellar normal in terms of the repulsive interaction between the chemical dissimilar copolymer blocks. We show that the tilting of the liquid-crystal director can lead to an adjustment of the lamellar period with an amplitude that is proportional the chain anisotropy. This reversible tuning of the lamellar period of block copolymers can lead to interesting applications in nanotechnology.

Level (Hons, MSc, <br> &nbsp; PhD, other)? PhD
Consider for a student <br> &nbsp; award (Yes / No)? No
Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)? Yes

Primary author

Dr Simiso Mkhonta (University of Swaziland)

Presentation Materials