Environmental Engineering Reference
In-Depth Information
hydrolysis, non-catalysed hydrolysis, a combination of both or a combination of
hydrolysis and monomer diffusion. This degradation study could be used in the design
of experiments to ind out the material parameters essential for the computer model.
This model was further extended to include the crystallisation process occurring
during the biodegradation of polymers [61].
There are no quantitative structure-activity relationship models for studying the
biodegradability of polymers. Some of the recently developed models in biodegradation
experiments such as the CATABOL-based models can predict metabolic pathways,
total biochemical oxygen demand and the amount of residuals at a speciic endpoint
[62]. But these systems have only been applied to small molecules. A lot of research
and effort have to be carried out to use these methods for predicting the biodegradation
of polymers. Also more data and sophisticated models are needed that can be applied
to many other polymeric systems.
6.2 New Material Design − Structured Material/Biodegradable
Polymers
Plastics provide an important alternative to natural materials because of their special
properties for a plethora of applications. The difference between metals and ceramics
when compared to plastic is the ability of the latter to 'creep' under load, or gradually
stretch or low when subjected to stress at room temperature. So in a very short
period of time they have become useful in a majority of the industrial applications.
However, as its production increases, waste plastic and its disposal become a huge
menace and they can potentially remain on earth forever. New polymeric materials
and composites are being designed for newer applications which also means that
one needs to address the issue of interaction of these new materials with the marine
environment and in turn their effect on the fauna and lora.
6.2.1 New Age Materials
New polymers with new properties that include conducting ability, shape memory
and so on, continue to be invented and innovative processes are being developed such
as nano-imprinting. Nanoelectronics is based on organic polymer-like structures that
could replace wires and silicon transistors. Liquid crystal polymers have 10-times
better moisture resistance, are rapidly shaped into precision 3D structures, and are
non-lammable without adding lame retardants. Because they only contain the
elements carbon, oxygen and hydrogen they may not have toxic chemicals impregnated
in them. So they could be termed 'green polymers'.
