THERM-A-SHIELD ®
THERM-A-SHIELD ® latex was specifically designed for superior wet and dry
adhesion to low and high-density foam. THERM-A SHIELD ® also exhibits excellent
adhesion to a variety of other construction substrates.
Typical Performance properties of THERM-A-SHIELD ® Elastomeric Roof Coating
Listed below are the individual properties inherent in THERM-A-SHIELD
technology. It is important to remember that it is the balance of these
properties that is unique to this chemistry. Although coatings based upon other
technologies may exhibit excellence in one or two performance properties, it is
the combination of all the properties that is required for a successful
elastomeric roof coating.
Durability
Since the advent of Plexiglas acrylic plastic sheet during World War II,
acrylics have been known for their exceptional durability, offering unequaled
resistance to degradation by sunlight and moisture. It was the UV resistance of
the acrylic polymer the lack of which is the major cause of failure in
conventional roof systems - that first led manufacturers to consider acrylic
polymers for elastomeric roof coatings. Through THERM-A-SHIELD® technology
these acrylic polymers have been tailored specifically for elastomeric roofing
applications, although THERM-A-SHIELD® affords many more hi-tech and practical
uses, such as hot and cold industrial plant pipes.
High-Temperature Advantages of Conventional Coatings
THERM-A-SHIELD®' s formulation of ceramic-filled product allows increased
insulation over the more conventional coatings now available.
Tensile Strength and Elongation
Thermal movement of a roof requires high tensile strength and elongation as
well. The tolerance for movement of these coatings is essential due to the
dynamic nature of a roofing substrate which expands and contracts due to
climatic conditions and the shifting and settling of the foundation.
These properties also give properly formulated elastomeric roof coatings the
needed flexibility and elasticity to withstand impact from foot traffic and
other abuse without rupturing.
Low Temperature Flexibility
Coatings for dimensionally unstable roofing substrates must have long-term
low-temperature flexibility. This is necessary to accommodate thermal expansion
and contraction of the substrate, so that coatings will not fail over an
extended period of time or with extreme weather conditions.
It should be
remembered that the effects of extreme weather conditions are not restricted to
cold climates. Evaporation of water after a sudden thunderstorm on a hot day in
any geographic location can rapidly drop the roof temperature as much as 100
degrees, causing severe thermal stress on the roof surface.
Roof coatings based on THERM-A-SHIELD® technology can withstand a 180 degree
flexibility bend at -15 degrees without cracking. Since there is no plasticizer
to migrate from the system, this flexibility is retained over time. Long term
resistance to cracking extends the life of the roof. It is important to note
that elastomeric roof coatings should exhibit good mechanical properties at room
and low temperatures before and after exterior exposure.
Stop Leaks
THERM-A-SHIELD® stops most small holes by application directly to surface
substrate.
Dirt Pickup Resistance
Polymers designed for THERM-A-SHIELD® elastomeric roof coatings combine the
inherent flexibility of pliable, low Tg polymers with long-term resistance to
dirt pickup. Without dirt pickup resistance, the roof coatings would quickly
darken with age. Because dark materials tend to absorb heat, dirt pickup can
significantly increase roof surface temperatures which, in turn, increases
interior temperatures and energy costs. THERM-A-SHIELD®-based coatings,
however, resist dirt pickup and retain their white, reflective appearance.
Test roofs have shown that after five years of exposure, the surface
temperature of the THERM-A-SHIELD®-based acrylic coating was 35 degrees cooler
that that of a conventional caulk polymer coating and 85 degrees cooler than a
black uncoated roof.
THERM-A-SHIELD® Elastomeric Coatings
Although designed specifically for superior wet and dry adhesion to high and low
density polyurethane foam. elastomeric roof coatings properly formulated with
THERM-A-SHIELD® latex polymer exhibit excellent adhesion to other typical
roofing substrates. A variety of ceramics, color chips and metal oxide pigments
can be used to produce tinted roofs. THERM-A-SHIELD®-based elastomeric roof
coating formulations can vary due to different climates.
Actual Performance Properties of
THERM-A-SHIELD® Ceramic Elastomeric Roof Coating
Tensile Strength and Elongation
THERM-A-SHIELD® ceramic insulating coatings expand and contract along the
roofing substrate to which they are applied because of their excellent tensile
strength, elongation and recovery properties. Resistance to cracking will be
maintained upon long-term exterior exposure because THERM-A-SHIELD® acrylic
does not require a plasticizer.
Typical tensile strength, elongation and recovery properties of
THERM-A-SHIELD® ceramic elastomeric roof coating are shown in Table 1.
|
Table 1-Typical Mechanical Properties of THERM-A-SHIELD® Ceramic Elastomeric
Roof Coatings |
|
Mechanical Properties After Two-Week Cure
70°/50% Relative Humidity |
|
Property |
74 Degrees F |
32 Degrees F |
0 Degrees F |
|
Percent Recovery |
65(65) |
54 (65) |
63 (52) |
|
Percent Elongation |
|
|
|
|
Maximum Stress |
240 (140) |
120 (110) |
80(70) |
|
Break |
245 (230) |
215 (180) |
130(120) |
|
Tensile Strength (psi) |
|
|
|
|
Maximum Stress |
173 (242) |
245 (394) |
728 (699) |
|
Break |
167 (232) |
220 (385) |
659 (699) |
|
|
|
|
Note: The numbers In parenthesis are alter an additional 50 hours Weather-Ometer
exposure. These numbers show noticeably lower elongation and higher tensile
strength than alter only a two-week cure. The additional Weather-Ometer exposure
ensures complete cure of the mastic and also leaches out the water-sensitive
components of the formulation, e.g. ethylene glycol, HEC thickener and
dispersants which act to hydroplasticize the roof mastic film. The use of
50-hour Weather-Ometer exposure or a "zero-point" is recommended for
monitoring changes that occur in accelerated or real-world exposure studies.
Other Performance Properties
Mechanical Properties
|
Room Temperature Tensile Strength |
670 psi |
|
Room Temperature Elongation |
460% |
| 0° F Tensile Strength |
2100 psi |
| 0° F Elongation |
100% |
|
Low Temperature Flexibility @ 180° Bend |
Passes @ -25°F |
|
Clear track Firm |
Low |
|
Adhesion to PUF(3) |
|
|
Dry (pound/inch) |
5 A/C |
|
Wet (pound/inch) 2A |
|
|
Perms 14 |
|
|
Water Swelling (30 days) |
8% |
|
(1) Mechanical properties measures using a 2 in/mm. crosshead speed
(2) Lowest temperature at which It passes a 1/8 Inch mandrel bend.
(3)A= adhesive failure.
C= Cohesive failure of the substrate.
Dirt Pickup-Resistance and Low-Temperature Flexibility
The combination of dirt pickup resistance and low-temperature flexibility is
unique to THERM-A-SHIELD® based on acrylic polymers formulated in THERM-A-SHIELD®. Surfaces coated with these formulations retain the initial
white, reflective color, thereby decreasing the exterior surface temperature of
the roof and further reducing interior building temperatures. This could mean a
savings in air conditioning costs.
It is necessary for roof mastics to have low-temperature flexibility because
they must accommodate the thermal expansion and contraction of the roof
substrate. In addition, they must resist the impact of hailstones prevalent in
most climates. Our THERM-A-SHIELD® ceramic formulation can be bent over 180
degrees over a 1/8 inch mandrel at 15 degrees without breaking.
Superior Adhesion to Polyurethane Foam
Formulations based on THERM-A-SHIELD® technology acrylics exhibit superior
adhesion to polyurethane foam. The standard 180 degree peel adhesion test
measures the wet and dry adhesion properties of an elastomeric roof coating
formulation.
Samples of THERM-A-SHIELD® acrylic were tested on an Inston Unit. According
to test results, the weakest point was found to be in the cohesive strength of
the foam rather than the bond between the roof mastic and the foam. The adhesion
data reveal that formulation of THERM-A-SHIELD® ceramic elastomeric actually
tore the adhesion during the test, This type of failure is referred to as
cohesive failure in the substrate. The conventional acrylic roof mastic failed
adhesively in the same test, and the value were significantly lower than those
recorded for our THERM-A-SHIELD® formulation.
The excellent peel adhesion data obtained in the laboratory were also found
in the tests run under the exterior exposure conditions. Results appear in
Tables 2 and 3.
| Table 2- Adhesion to Polyurethane Foam |
|
Formulation Binder |
THERM-A-SHIELD® |
Conventional Acrylic
Roof mastic Latex |
|
Peel Adhesion (lb./in.) |
Peel Adhesion (lb./in.) |
|
Foam Density (lb./ft) |
Dry1 |
Wet2 |
Dry1 |
Wet2 |
|
2.5³ |
5.OC |
3.OC |
1.OA |
< 0.2A |
| 3.5³ |
3.5C |
2.OC |
1.OA |
< 0.2A |
| 4.04 |
3.6C |
3.5C |
1.OA |
<0.2A |
|
A = Adhesive Interfacial Failure |
|
C= Cohesive Failure In Substrate |
1 Sample cured two weeks at 750F/250C and 50%
relative humidity and tested.
2 Sample cured two weeks at 750Ffl?C and 50% relative humidity and then immersed
in water for one week and tested while wet.
3 Smooth Surface texture.
4 Orange peel surface texture.
|
Table 3 - Adhesion of THERM-A-SHIELD® Acrylic to Polyurethane Foam after Exterior
Exposure |
|
|
|
|
Cure Time |
Adhesion |
Failure |
|
One week dry1 |
4.8 lb/in. |
Cohesive |
|
One week dry plus one
week water soak² |
4.1 lb/in. |
Cohesive |
|
Eight Weeks exterior3 |
4.4 lb./in. |
Cohesive |
|
Twenty-eight weeks exterior3 |
4.0 lb./in. |
Cohesive |
|
Two years exterior |
5.0 lb./in. |
Cohesive |
|
|
|
|
|
|
1 Sample cured two weeks at 750F/25C and 50% relative humidity and tested one
week and tested while wet.
2 Sample cured two weeks at 750F1250C and 50%
relative humidity and then Immersed
In water for
3 samples exposed horizontal face up, Southeastern Pennsylvania. Samples not
cured in the laboratory.
Long Term Exterior Roofing Exposure
Early prototypes of THERM-A-SHIELD® ceramic based coatings have been on
exposure since the late 1980's and in actual roofing applications since 1989.
These exposures continue to demonstrate excellent performance.
THERM-A-SHIELD® ceramic elastomeric roof coating formulation also has
excellent adhesion to many common construction substrates. Some examples are in
Table 4.
| Table 4 - Adhesion of THERM-A-SHIELD® Ceramic Elastomeric to Common
Construction Substrates |
|
Peel Adhesion (lb./in.) |
|
Substrate |
Dry1 |
Wet2 |
|
Polyurethane Foam |
5.0 cp |
3.5 cp |
|
Galvanized Steel |
5.0 cp |
2.0 cp |
|
White Pine |
6.0 cp |
0.5 A |
|
APP Modified Bitumen |
1.3 |
0.4 A |
|
Asphalt Shingles |
1.5 A |
0.5 A |
|
A= Adhesive Failure |
|
C = Cohesive PEAK Failure |
1 Sample cured two weeks at 750F1250C and 50% relative humidity and tested.
2 Sample cured two weeks at 750F/250C and 50% relative humidity and then
immersed In water for one week and tested while wet.
Safe Handling Information
Based on final composition, THERM-A-SHIELD® elastomeric acrylics are not
expected to be acutely toxic. There may be a slight moderate skin, eye, or
respiratory irritant.
THERM-A-SHIELD® Material Safety Data Sheets (MSDS) contain pertinent data
that you may need to protect your employees and customers against any known
health or safety hazards associated with our products.
MSDS SHEET: Click Here
Under the OSHA Hazard Communication standard, workers must have access to
and understand MSDS on all hazardous substances to which they are exposed. Thus,
it is important that you provide appropriate training and information to your
employees and make sure they have available to them MSDS on any hazardous
products in their workplace.
Environmental Coating Systems sends MSDS on non-OSHA hazardous as well as
OSHA-hazardous products to both the "bill to" and "ship to"
locations of all our customers upon initial shipment (including samples) of all
of our products (whether or not they are considered OSHA-hazardous). If you do
not have access to one of these MSDS, please contact your local Environmental
Coating Systems representative for an additional copy. Updated MSDS are sent on
an annual basis to all customers on record.
MSDS should be obtained from the suppliers of other materials recommended in
this bulletin.
LIGHTWEIGHT CERAMIC
| Form |
Hollow Spheres |
| Composition |
Silica-Alumina Ceramic Alloy |
| Color |
White |
| Specific Gravity |
.7- .9 g/cc |
| Particle Size Range |
10 - 300 microns |
| Ph in Water |
6-8 |
| Specific Conductance in 1% Slurry |
Maximum 25 Micro Mohs/cm |
| Softening Point |
22000 F |
| Hardness Mohs Scale |
5 |
| Compressive Strength |
5,000 psi |
| Free Moisture |
0.2% Maximum by Weight |
| Thermal Conductivity |
0.69 Btu/hr/SL2/F/in |
Coefficient of Thermal Expansion
|
d=8 X 10 -6 |
|
Electrical Resistance |
1015 ohm cm |
| Dielectric Constant |
1.608 @1000 KH |