Micro- and Nanostructures from Liquid Crystalline Cellulose Materials
Abstract
The objective of the project was to produce, for the first time, helical gold cellulosic nano and micro wires. Electrospinning was used to produce right and left handed fibers. The use of these helical objects, as templates for gold nanoparticles, implicated the control of the helices pitch and diameter and also the separation of the right from left handed helices. To achieve this performance it was crucial to understand the mechanism that was responsible for the helical winding. In order to investigate the origin of the intrinsic curvature found in the cellulosic fibers, morphological and structural features were investigated by means of nuclear magnetic resonance imaging (MRI) and polarizing optical microscopy (POM). POM images and MRI measurements indicated that the presence of off-axis disclination lines, embedded in the cylindrical fibers, was the explanation for the observed helical winding. Preliminary MRI results indicate that the presence of gold nano particles enhanced the intrinsic curvature of the fibers by promoting the existence of more disclinations lines defects along the fiber.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 03, 2011
- Accession Number
- ADA541365
Entities
People
- Maria H. Godinho
Organizations
- NOVA University Lisbon