A numerical study on the thermal expansion coefficients of fiber

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or brown (Wypych, 2000). Cellulose fibers (especially virgin materials) have a
complex morphological structure which facilitates reinforcement (Figure 2.7).
Figure 2.7 The morphology of cellulose fibers (Wypych, 2000).
2.2.2.5.2 Oriented Polyethylene Fibers
Polyethylene is the most popular plastic in the world. This is the polymer that
makes grocery bags, shampoo bottles, children's toys, and even bullet proof vests.
For such a versatile material, it has a very simple structure, the simplest of all
commercial polymers. A molecule of polyethylene is nothing more than a long chain
of carbon atoms with two hydrogen atoms attached to each carbon atom (Figure2.8).
The chain of carbon atoms may be many thousands of atoms long.
Figure 2.8 The molecule of polyethylene.
The ultrahigh molecular weight polyethylene fiber is a highly crystalline fiber
with very high stiffness and strength. This results from some innovative processing
and control of the structure of polyethylene. The unit cell of a single crystal