Polymers are everywhere, also inside of the human body.
Why polymers are so important?
The most general answer is: because they are solid. With the
term “polymer” we describe long chains consisted with repetitive
structure, and longer chains tend to be solid. Classical
forensic polymer engineering concerns a study of failure
in solid polymer products. This area of science comprises
fracture of plastic products, or any other reason why such a
product fails in service, or fails to meet its specification. Environmental
stress cracking (ESC) is one of the most common
causes of unexpected brittle failure of thermoplastic (especially
amorphous) polymers. The rate of ESC is dependent on
many factors, including, for example, the polymer’s chemical
composition, bonding, crystallinity, surface roughness, molar
mass and residual stress. It also depends on the chemical nature
of liquid media and the temperature of the system.
The most familiar synthetic polymers include nylon, polyethylene,
polyvinyl chloride, polytetrafluoroethylene and
polyesters, whereas proteins, nucleic acids, cellulose, starch,
glycogen, silk, wool and aliphatic biopoliesters (PHA) are the
polymers occurring in nature.
So far, most of the reported forensic polymer engineering case
studies concern ex-post investigations of traditional polymeric
materials or their thermoplastic composites. (Bio)polyesters
are recently of particular importance due to their biodegradation
opportunity and potential medical applications. When the
development of biodegradable polymers was in its infancy the
most crucial features were concentrated on the effect of macromolecular
architecture, new monomer systems, polymerization
mechanisms, and different polymerization techniques
on the final biodegradable properties. Significant eforts have been directed towards specific areas, such as mechanisms of
biodegradation, biocompatibility, processing conditions and
potential applications in medicine, protection of environment
and agro chemistry. However, such aspects like bio-safety of
such advanced polymers or nano-safety of their composites
were and still are frequently neglected.
The knowledge and impetus for development of forthcoming
advanced polymeric materials comes from identification
of problems before they arise.
This novel viewpoint focuses
on prediction, evaluation and indication on potential complications
arising from the use of advanced polymers. Associations
between polymeric materials’ structures, properties and
behaviors before, during and after practical applications can
be evaluated by the use of the methodology developed by Forensic
Engineering of Advanced Polymeric Materials (FEAPM).
Optimization and characterization of the polymers’ properties
are very important for their production, usage and utilization.
The connecting of all these elements in the FEAPM methodology
constitutes the novelty of this approach. This should help
to project new advanced polymeric materials, avoiding the
product defects generated during production and usage.
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