Acrylite AR®
Acrylite AR sheet is a continuously
manufactured acrylic sheet with an abrasion resistant coating on
one or two sides. This coating significantly increases the abrasion
resistance and chemical resistance of the sheet while maintaining
the outstanding properties associated with Acrylite FF acrylic sheet.
Acrylite AR sheet combines abrasion resistance and
chemical resistance with the excellent optical quality and ease
of fabrication inherent to Acrylite FF sheet. Acrylite AR sheet
resists marring and scratching which can be caused by frequent cleaning
and/or constant public contact. Most spray painted graffiti can
also be removed without damage to the sheet. The protection afforded
by Acrylite AR sheet results in a harder surface thereby significantly
extending the service life of the product. Care should be taken
to avoid chemical contact on uncoated areas of the sheet.
Abrasion
Resistance
In assessing
abrasion resistance, a distinction can be made between frictional
abrasion and impact abrasion. These two types of abrasion are evaluated
by different test methods, Taber Abrasion and Falling Sand. An effective
way to quantify the performance of an abrasion resistant coating
is to report the percent change in haze after testing. Acrylite
AR sheet significantly reduces the effects of both frictional abrasion
and impact abrasion.
Weathering
Acrylite AR sheet withstands
the adverse effects of outdoor weathering. The abrasion resistant
properties are maintained during prolonged periods of outdoor use.
Accelerated weathering studies indicate that there is no significant
loss in light transmittance or any appreciable increase in yellowing,
as measured by the yellowness index after an accelerated weathering
period of three years.
Characteristics
- top
Acrylite
AR abrasion resistant sheet is a lightweight, rigid and weather-resistant
thermoplastic. Acrylite AR sheets are dimensionally stable and resistant
to breakage. The ease of fabrication allows the product to be used
in a wide variety of applications, including the following:
• Displays
• Signs
• Menu Boards
• Transportation Glazing
• Architectural Glazing
• Museum Display Cases
• Picture Frames
• Sports Facilities
Glazing
- top
Acrylite AR
sheets are recommended for use in flat, vertical, architectural
glazing. Certain considerations must be taken into account before
cutting sheets for installation. Acrylite AR sheets will expand
and contract with a change in temperature. A 8" panel will expand
or contract approximately 0.002" for each degree change in temperature.
Calculations should be made at the installation temperature for
proper sizing.
In a vertical application, there will be no foreshortening due to
cold flow. Slight bowing can occur under certain temperature and
humidity conditions in the direction of the higher temperature or
humidity. This condition is reversible. The panel will revert back
to its original flatness when the temperature or humidity is equalized
on both sides of the panel. Maximum wind load and window size
must be considered in selecting glazing panel thickness. Table 1
gives recommended panel thicknesses for different size openings.
The thickness in the graph applies to rectangular windows with widths
less than 3/ of their lengths. For larger widths, use the next larger
thickness. For long, narrow windows, whose length exceeds four times
their width, use the next smaller thickness.
|
Table
1: |
|
| 50 |
 |
|
|
5 |
|
|
0 |
|
| 35 |
|
| 30 |
|
| 25 |
|
| 20 |
|
| 15 |
|
|
10 20 |
30 |
0 |
50 |
60 |
70 |
80 |
90 |
100 |
110 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Panels
' x ' or larger need to be glazed using a dry gasket system. This
allows the sheet to expand and contract while maintaining a weather-tight
seal. Flexible sealants and tapes can be used for panels smaller
than ' x '.
Acrylite AR sheets should not be fastened with bolts or screws.
Localized point stresses in excess of 1 ,500 psi may cause cracking
of the sheet.
Fabrication
- top
Machining
Acrylite AR
sheets can be sawed, routed, drilled and machined using the same
techniques as Acrylite sheet products. For details on tooling and
proper procedures for Acrylite AR sheet, refer to the Acrylite sheet
data. When performing machining operations, keep masking applied
and the work area free of chips to help prevent gouging of the sheet
surface.
Edge Preparation
Scraping,
wet sanding and buffing are acceptable methods to prepare a finished
edge. Flame polishing is not recommended. Overspray from the flame
may cause the surface coating to crack or craze. This may lead to
delamination of the coating and a loss of abrasion resistance.
Cementing
Acrylite AR
sheets are available with either one or two sides coated for protection
against abrasion. When cementing to a non-coated sheet surface,
use the same solvent or polymerizing cements commonly used for Acrylite
sheet products. The most critical factor is the edge of the part
to be cemented. The edge must first be properly prepared with low
stresses. Annealing of the part prior to cementing is recommended.
Solvent cementing to a hard coated surface cannot be readily accomplished
due to the chemical resistance of the coating. To solvent cement
on or to a coated surface, the coating first must be removed by
sanding or routing. When removing the coating, insure that the bonding
surface is flat, clean, and free of stress. Annealing the piece
will insure a stress-free surface.
Thermoforming
Line bending
or thermoforming Acrylite AR sheet is not recommended. The abrasion
resistant, hard coat surface does not soften when heated. The coating
will separate and crack in the heated region, leaving an optically
poor line-bent area. This area can lose its abrasion resistant properties.
Thermoforming of larger areas, even the forming of shallow domes,
will result in crazing of the coated surface. Therefore, no method
of heat forming is recommended for either one or two side coated
products.
Cold Forming
Bending of
the coated sheets into a generous radius can be done. To calculate
the minimum radius of curvature, multiply the thickness of the sheet
to be used by 330 for Acrylite AR sheets. Tighter radii may result
in crazing or cracking of the coating and may lead to a loss of
abrasion resistant properties.
Flammability
Acrylite
AR sheets are combustible thermoplastics. Precautions should be
taken to protect these materials from flames and high heat sources.
Good judgment should be take in the use of these versatile materials
and recommend that building codes be followed carefully to assure
they are used properly.
Acrylite AR abrasion resistant acrylic sheet usually burns rapidly
to completion if not extinguished. The products of combustion, if
sufficient air is present, are carbon dioxide and water. However,
in many fires, sufficient air will not be available, and toxic carbon
monoxide will be formed as it will from other common combustible
materials.
Code
Approval - top
Acrylite
AR sheets has met the requirements to comply to the following regulations:
• ANSI Z97.1 Safety Glazing Materials Used in Building
• ANSI Z26.1 Safety Glazing Materials for Glazing Motor Vechiles
• Uniform Building Codes ICBO, BOCA, and SBCCI
• Consumer Product Safety Commission, Architectural Glazing
Material Safety Standard, (16 CFR 1) Categories I & II
Chemical
Resistance - top
Acrylite
AR abrasion resistant sheets can withstand certain chemicals that
may come in contact with the coating. Table 2 shows how the coating
helps provide better protection against certain chemicals. Care
should be taken to avoid contact of certain chemicals to the unprotected
edges or surface of the sheet. Some of the listed chemicals may
cause swelling or crazing on the uncoated side of sheets.
| Table 2-- Chemical Resistance
- top |
| Chemical |
Acrylite AR Sheet |
Acrylite FF Sheet |
| Acetone |
>
15 min |
<
15 min |
| Ethylene
Dichloride |
>
2 hrs |
<15
min |
| Gasoline |
>2
hrs |
>2
hrs |
| Hydrochloric
Acid |
>2
hrs |
>2
hrs |
| Methyl
Alcohol |
>2
hrs |
>2
hrs |
| Methylene
Chloride |
>2
hrs |
<15
min |
| Methyl
Ethyl Ketone |
>1
hr |
>15
min |
| Nitric
Acid |
>1
hr |
<15
min |
| Sodium
Hydroxide |
<2
hrs |
<2
hrs |
| Sulfuric
Acid |
>15
min |
<15
min |
| Toluene |
>1
hr |
<15
min |
| Isopropanol |
>24
hrs |
>24
hrs |
| Kerosene |
>24hrs |
>24
hrs |
| Testing
the resistance of the above chemicals was conducted per ASTM
8. Time intervals for visually inspecting the sheet
surface; 15 minutes, 1 hour and 24 hours. The table
shows the time it took the chemical to visually attack the
surface. |
Cleaning
To clean
off the surface of Acrylite AR abrasion resistant sheets, a liquid
detergent and water solution is recommended. There are commercially
available cleaners that also work well without damaging the coated
surface. It is not recommended to use abrasive cleaners on the sheet
surface. The following brand name cleaners have been tested and
found to work well on coated surfaces.
CAUTION: Some of these cleaners may attack the uncoated side
of the sheet.
-
Fantastik
household cleaner
-
Mr.
Clean household cleaner
-
Formula
409 household cleaner
-
Top
Job household cleaner
-
Glass
Plus cleaner
-
Windex
window cleaner
To remove
paint, ink and graffiti from the coated surface, use a soft cloth
soaked in either Isopropyl Alcohol or VM&P Naphtha. Then immediately
wash and rinse off residue using a liquid detergent and warm water
solution. Never use mechanical methods, such as razor blades, putty
knives or scrapers on the surface of the sheets. This may lead to
gouging and removal of the hard coat. Once the coating has been
removed, it cannot be repaired.
Physical
Properties - top
| Property |
ASTM Method |
Typical Substrate Value (3.0mm) |
| Mechanical |
| Tensile
Strength
Elongation,
Rupture
Modulus
of Elasticity |
ASTM
D 638 |
10,000
psi
4.5%
400,000 psi |
| Flexural
Strength
Modulus
of Elasticity |
ASTM
D 790 |
17,000
psi
480,000 psi |
| Izod
Milled Notch
Instrumented
Dart |
ASTM
D 256
ASTM D 3763 |
0.4
ft.lbs./in.
19 in.-lbs. |
| Optical |
| Light
Transmission, Total |
ASTM
D 1003 |
92% |
| Thermal |
| Deflection
Temperature Under Load (264 psi) |
ASTM
D 648 |
195°F |
| Vicat
Softening Point |
ASTM
D 1525 |
230°D |
| Coefficient
of Linear Thermal Expansion |
ASTM
D 696 |
0.000040
in/in-°F |
| Coefficient
of Thermal Conductivity |
ASTM
C 177 |
1.3
BTU/hr.ft2-°F |
| Flammability |
| Burn
Rate |
ASTM
D 635 |
1.0
in/min |
| Self-Ignition
Temperature |
ASTM
1929 |
830°F |
| Smoke
Density Rating |
ASTM
2843 |
10% |
| Abrasion
Resistance of the Coating
Change in Haze |
| Tabor
Abrasion (100 Cycles) |
ASTM
D 1044 |
0.8% |
| Mar
Resistance (3,000 grams) |
DIN
52 348 |
6.8% |
|