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Polycarbonates are considered to be special types of polyesters in which groups of dihyudric
phenols are linked through carbonate groups. Perhaps one of the best known trade names in plastics is Lexan
which is a polycarbonate. Polycarbonate, with its mechanical and engineering applications,
will be reviewed here.
While more than a dozen performance characteristics of polycarbonate are utilized singly or in combinations,
seven are most commonly relied on. These are high impact strength, water-clear transparency, good creep
resistance, wide use temperature range, dimensional stability, abrasion resistance, hardness, and rigidity
despite its ductility.
Polycarbonate's properties are unique for a thermoplastic material. It is the toughest material that
you can see through. Polycarbonate is many times stronger than acrylic, yet has the toughness and ductility associated
with the softer and more rubbery materials. Polycarbonate has high resistance to deformation under load
and at temperature extremes and its thermal expansion and contraction is significantly below that of
acrylic or butryate.
In addition to clear and colored sheet, polycarbonate is available in rod, tubing, extruded profiles, and film.
Properties
Excellent impact strength
Transparent up to 2" in special grades
Good dimensional stability
Very good thermal stability
Exceptional machinability
High dielectric strength
High volume resistivity
UL 94 V-2 @ .236" thickness
Applications
| Signs |
| Machine guards |
| Window glazing | |
| Insulators |
| Security glazing | |
| Guides |
| Shields | |
| Bushings |
| Optical lenses | |
| Compact discs |
Tolerances
.250" - 1.000" +.002" -.000"
1.125" - 2.000" +.010" -.000"
2.125" - 2.750" +.015" -.000"
2.875" - 4.750" +.187" -.000"
5.000" & over +.250" -.000"
Standard Colors: Translucent, black, gray, white translucent sign colors
Specification: LP-393
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