Unisil HS Technical Data Sheet

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GAF Liquid-Applied
Technical Data Sheet
December 2016, supercedes January 2016
Unisil HS Roof Coating
United Coatings
™
Unisil HS Roof Coating is a high-
solids, moisture-cure silicone coating that provides superior
weatherproofing, ultraviolet resistance, biological resistance,
and fire retardancy over polyurethane foam insulation and
other appropriate substrates. The pure silicone polymers are
naturally fire retardant to provide long-term fire resistance,
while the tight surface finish affectively resists the attach-
ment of algae, mildew, and mold organisms.
PRODUCT DESCRIPTION
United Coatings
™
Unisil HS Roof Coating is designed
to be applied over SPF insulated concrete, metal,
and ambient and hot tanks. It is built for protecting a
wide range of substrates from the effects of moisture
intrusion and weathering, and is particularly effective as
a protective coating over polyurethane foam on new or
existing roofs.
Unisil HS Roof Coating is a single-component
elastomer that exhibits a rapid cure when exposed to
ambient conditions.
Advantages:
• Long-term elastomeric properties from sub-zero
temperatures to high heat
• Resistance to weathering – No deleterious effects
on coating after 5,000 hours of continuous
exposure
• Low VOC
BASIC USES & ADVANTAGES
5-gallon (18.9 liter) pail
50-gallon (189 liter) drum
Shelf Life: 18 months from date of manufacture in unopened
containers, if stored properly in a clean and well-ventilated
area at 40°F – 90°F (4°C – 32.2°C). Storage outside this
temperature range may shorten shelf life. Keep containers
covered when not in use. Do not allow coating to freeze.
PACKAGING & SHELF LIFE
UNISIL HS ROOF COATING
Solids by Weight
96% (±2) [ASTM D1644]
Solids by Volume
96% (±2) [ASTM D2697]
Flash Point (COC)
290°F (143°C) [ASTM D92]
Dry Time to Walk On
2 – 4 hours @ 75°F (24°C),
50% R.H.
Tensile Strength
330 psi (2.3 MPa) (±25)
[ASTM D2370]
Elongation
200% (±10) [ASTM D2370]
Hardness
45–55 Shore A [ASTM C661]
Permeance
5.9 US Perms @ 30 mils (762 microns)
[ASTM E96, Procedure B]
VOC
<50 g/L [ASTM D3960]
Specific Gravity
1.29 @ 77°F (25°C) [ASTM D1875]
Flexibility After
Weathering
After 5,000 hours exposure in the
QUV Accelerated Weathering Cabinet,
Unisil HS Roof Coating retains its
ability to withstand multiple 1" (25.4
mm) mandrel bends at 2°F (-17°C)
without cracking. [ASTM D4338]
Solar Reflective
Index (SRI)
110 - Unisil HS White [ASTM E1980]
Emissivity
0.89 - Unisil HS White [ASTM C1371]
PHYSICAL PROPERTIES
Application
Temperature
40°F – 105°F (5°C – 40°C)
(air, surface)
Dry Time (Touch)
(Light rain & foot
traffic)
White @ 5 hours @ 70°F (21°C) 50%
R.H. @ 16 wet mils (0.41 mm)
Water Absorption
0.1% weight gain after 2 weeks
immersion at 75°F (24°C)
[ASTM C1371 / ASTM D471]
Temperature Limits
for Normal Service
Conditions
-80°F to 350°F (-62°C to 177°C)
Max 185°F (85°C) continuous
temperature
High-Temperature
Stability
Tested in thermostatically controlled
heat chamber. Will not age, harden,
or slump at temperatures up to 350°F
(177°C). [ASTM D794]
Low-Temperature
Flexibility
Capable of withstanding 180° bends
over a 1" (25 mm) mandrel @ 2°F
(-17°C). [ASTM C734]
Resistance to
Freeze-Thaw
Test panels exposed to freeze-thaw
cycles under complete immersion in
deionized water. Cycles consisted of 16
hours at 0°F (-18°C) and 8 hours at 70°F
(21°C). After 4 complete cycles, the
physical integrity of the coating remained
unaffected. There was no loss of
adhesion and no blistering or softening.
Standard Colors
White, Light Gray, Gray, Light Tan,
and Tan.
Substrate Preparation: Surfaces to be coated shall be
completely dry and free of any degraded foam, grease, oil,
dirt, or other contaminants that could interfere with proper
adhesion. Any physical damage shall be repaired before coat-
ing application commences.
Mixing: Mix containers with an air-driven power mixer,
taking care not to incorporate air into the product. Use imme-
diately to avoid reacting in the container with trace amounts
of moisture. Containers that have been stored for any length
of time may develop a skin/film on top of the coating; this
should be removed prior to mixing.
Application: United Coatings
™
Unisil HS Roof
Coating is best suited for airless sprayer equipment. Apply
evenly at a rate of 1 gal/100 ft² (4.1 L/10 m²) per coat.
Each coat shall be applied in a direction perpendicular to the
previous coat. Edges of flat roof areas shall be precoated in a
“picture frame” configuration.
The best adhesion of subsequent layers will occur when the
initial layer of silicone is dry enough to walk on. Silicones are
moisture-cured, therefore increased humidity will shorten dry
times and low humidity will extend dry times. Regardless of
conditions, the period of time between coats must not exceed
24 hours.
APPLICATION INFORMATION
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