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POLYVINYL
CHLORIDE (PVC)
Vinyls are a broad and diversified group of materials.
Rigid vinyl sheeting is available in three categories:
Calendered Sheet
Planished Sheet
Extruded Sheet
Calendering is
the manufacturing process, and sheet is available in .005-.020"
thicknesses. Planished sheet is
calendered sheet that has been laminated using polished or matte finish plates
to give the finished sheet a polished or matte finish.
Planish sheet is available in .10" - .125" thicknesses.
Special order thicknesses are also available.
Calendered
rigid vinyl sheet is available in a full range of colors.
Calendered sheet is also less expensive, due to in part to not having the
processing time that other sheet needs.
Calendered
sheet is brittle because of the considerable strain imposed during
manufacturing. Calendered sheet may
be used in lieu of planished sheet, at a reduction in cost, if further
processing and laminating is required.
Planished
rigid sheet is available in a variety of thicknesses and colors.
It is available in transparent, translucent, and opaque formulations, and
in standard and high impact forms. For
workability, high impact formulations are more desirable.
Clear standard formulations are more rigid and haze free.
Planished sheet is used for a wide variety of applications including:
Face Shields
Safety
Shields
Drawing Instruments
Lamp Shades
Dial Covers and Faces
Scales
Lighting Diffusers
Menus
Shims
Insulating Spacers
Airline Seat Pocket Cards
Decorative Applications
The
advantages of rigid vinyls are:
Clarity
Low Moisture Absorbtion
Dispersion
Easy to fabricate
Excellent chemical resistance
Good dimensional stability
Good draw characteristics
Good flexural strength
Good range of forming temperature (280 0– 300
0 F)
Self-Extinguishing
Excellent electrical properties
The
disadvantages of rigid vinyls are:
Poor weatherability
Relatively low impact strength
Heavy
Easily scratched or marred
Low heat distortion point (1600
F)
Flexible vinyl
sheet and film comes in a myriad of appearances.
It can be skin soft to semi rigid. It
can come in any color and can be formulated to meet specific applications.
Some of the applications for the flexible vinyls are:
Seat Covers
Shop Aprons
Protective Gloves and Clothing
Rainwear
Anti-corrosive Liners
Inflatable Toys
Hospital Equipment
Novelties
Fabrics
Shower Curtains
Storm Windows and Draperies
Its
applications are almost unlimited. Many
of the advantages of rigid vinyls are also advantages to flexibles.
In addition, flexibles are tear and puncture resistant, abrasion
resistant, easily fabricated and they are non-toxic.
PVC
is the oldest sheet and tube product in the market used for corrosion resistant
tanks, ducts, fume hoods and pipes. PVC
tanks are very popular with etchers and metal chrome platers.
Photography labs use many types of standard and custom made tanks to
contain corrosive solutions. PVC
will withstand temperatures over 1400
for short periods but it is not recommended for higher
temperatures.
Unlike other
olefins, PVC can be cemented together, although heat welding is more acceptable
for joining them together. Rigid
PVC is available in sheets, bars, rods, tubes, pipe fitting valves and large
diameter ducting over 24 inches.