|
Abstract:
|
The search for new materials especially those possessing special
properties continues at a great pace because of ever growing demands of the
modern life. The focus on the use of intrinsically conductive polymers in
organic electronic devices has led to the development of a totally new class of
smart materials. Polypyrrole (PPy) is one of the most stable known conducting
polymers and also one of the easiest to synthesize. In addition, its high
conductivity, good redox reversibility and excellent microwave absorbing
characteristics have led to the existence of wide and diversified applications for
PPy. However, as any conjugated conducting polymer, PPy lacks processability,
flexibility and strength which are essential for industrial requirements. Among
various approaches to making tractable materials based on PPy, incorporating
PPy within an electrically insulating polymer appears to be a promising method,
and this has triggered the development of blends or composites. Conductive
elastomeric composites of polypyrrole are important in that they are composite
materials suitable for devices where flexibility is an important parameter.
Moreover these composites can be moulded into complex shapes.
In this work an attempt has been made to prepare conducting elastomeric
composites by the incorporation of PPy and PPy coated short Nylon-6 fiber
with insulating elastomer matrices- natural rubber and acrylonitrile butadiene
rubber. It is well established that mechanical properties of rubber composites
can be greatly improved by adding short fibers. Generally short fiber
reinforced rubber composites are popular in industrial fields because of their
processing advantages, low cost, and their greatly improved technical
properties such as strength, stiffness, modulus and damping. In the present
work, PPy coated fiber is expected to improve the mechanical properties of the
elastomer-PPy composites, at the same time increasing the conductivity. In
addition to determination of DC conductivity and evaluation of mechanical
properties, the work aims to study the thermal stability, dielectric properties
and electromagnetic interference shielding effectiveness of the composites.
The thesis consists of ten chapters. |