Introduction To Fiberglass - Columbia Coronado 25 Owenrs Manual

6.1

INTRODUCTION TO FIBERGLASS

6.1.1 Composition and Properties of Glass Fibers
Glass is a combination of several common raw materials such as silica (sand),
line, and alumina, plus small percentages of other elements. Among known solid
materials, glass is unique in that it has no detectable crystalline structure.
It is essentially a supercooled liquid of immeasurably high viscosity and
surface tension.
Glass potentially has very high strength. This is one reason it is produced in
fibers that are then combined to form the tough, high-impact-strength material
known as fiber glass and used as a reinforcement for plastics. On a
pound-for-pound basis, glass fibers are actually stronger and stiffer than
steel.
E-glass fibers are the most common in use today because of their low cast and
good fiber forming characteristics, strength, and electrical properties.
Glass fibers normally have a sizing (coating) applied during their manufacture.
There are various types of sizings, but all have some common purposes:(1) to bind
mono-filaments together into a more easily handled fiber called
a strand, (2) to lubricate monofilaments so that they do
not abrade and break each other and thus cause reduced strand
strength, and (3) to promote surface contact between the
fiber and the laminating resin -- that is, to increase fiber
wettability. Special purpose sizings are sometimes applied
to alter the properties of the glass fibers.
6.1.2 Forms of Commercial Glass Fiber
Glass fiber materials are supplied commercially in the form o£ roving, woven
roving, and cloth. Another form is milled fibers, which are mixed with resin to
serve as a filler and stiffener in patching putty.
6.1.3 Resins
Glass fiber materials are laminated with plastic resins to form
fiber-glass-reinforced plastic products, such as boats and automobiles.
Commercially available laminating resins are synthetic polymers of a class
called polyesters. Most
SECTION 6
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