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The world has become more insecure in the last decade due to widespread
terrorism, particularly post 9/11. More protection is now required
against ballistic attacks.
A product that is ideally suited for such an application has to
very light, flexible over wider temperature range and yet very strong.
UHMWPE fiber invented by DSM way back in 1979 and first commercialised
in 1990, indeed fits the requirements very well. This product has
a very high degree of orienation (almost 95%) and very high crystallinity
(almost 85%). It is almost 15 times stronger than steel of the same
weight. The typical tenacity of such a fiber is 45 grams/denier.
Besides being stronger, it has the ability to absorb extremely high
amount of energy. No wonder that these fibers find increasing usage
in light-weight bullet-resistant vests, helmets, vechicle armour
and bulletproof cockpit doors. Due to extremely good strength, these
fibers find usage in performance ropes, cables, cordage fishing
nets /lines as well as safety gloves and sports articles.
These superstrong UHMWPE fibers are produced by gel spinning process
in which the polymer is first dissolved in a solvent and then spun
through spinnerates. The process is patented globally by DSM. The
fibers developed by DSM are called "Dyneema". DSM also
licenced the process to Allied Signal in USA in the early nineties.
The fiber produced by Allied Signal is called "Spectra".
There are essentially two types of Dyneema products that are now
available. In addition to the fibers, sheets are produced by placing
these fibers in the same direction. They therefore attain very high
strength. These sheets are known as "Dyneema UD" and are
found to be invaluable against ballistic attacks. No wonder that
the American Chemical Society has recognized the contribution of
DSM scientists by awarding "Heroes of Chemistry Award".
Their contribution to protect human beings against mindless terrorists
attack is indeed very valuable.
DSM is now increasing the manufacturing capacity both in USA and
the Netherlands to reach a level of 2000-3000 tonnes by 2002 and
4500 tonnes by 2005 at a cost exceeding 100 million euro.
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