Technical Data Sheet
QM 237
Quantum Silicones鈥? 37 Durometer Addition Cure
Moldmaking Material
Product Description
Quantum Silicones鈥? QM 237 is a two component, room temperature addition cure
silicone material. The cured rubber has excellent mechanical properties and good
shelf-life stability. This material is a good choice for the molding of furniture, picture
frames and architectural materials. In addition, this QM 237 is exceptionally good where
highly detailed parts and mold flexibility are required.
Key Features
Low viscosity
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Fast demold time
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Casting resin resistance
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Excellent flexibility
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Main Applications
Molds for architectural replication
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Molds for polyester, epoxy, and rigid or foam polyurethane resin casting
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Molds for technical articles and prototypes
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Molds for furniture and picture frame replication
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Candy and other food molds
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Typical Properties
UNCATALYZED PROPERTIES
Mix Ratio 10:1 by weight
BASE QM 237A
Base Appearance Beige
Base Viscosity, cps 20,000
Base Specific Gravity, g/cm3 1.32
CATALYST QM 237B
Catalyst Appearance Dark Blue
Catalyst Viscosity, cps 2,000
Catalyst Specific Gravity, g/cm3 0.97
Typical Properties Continued
CATALYZED PROPERTIES-QM 237
PROPERTY QM 237
Catalyzed Color Dark Blue
Catalyzed Viscosity, cps ~10,000
Pot Life(1)(minutes) 35 minutes
Demold Time(hours) 6 to 8 hours
TYPICAL CURED PROPERTIES (3 DAYS @ 25C)
Durometer, Shore A 37
Tensile Strength, psi 580
Elongation, % 600
Linear Shrinkage, % <0.1
Useful Temperature Range -60C to 204C
(1)Pot Life is defined as the time at which the catalyzed viscosity has doubled.
Cure Characteristics
The curing process begins as soon as the catalyst is mixed with the base. Under
normal temperature (25C) and humidity (50% RH) conditions, the material will cure as
described in the data above. Because this system is sensitive to heat and humidity, a
change in cure speed may be seen if one or both of these variables are altered. Any large
difference in temperature (+/-5C) or humidity (>60-70%) may change the cure profile of
the material. In addition, if the product is to be used with aggressive resins such as high
styrene polyester resins, it is recommended that the rubber be allowed to cure for 48
hours. For best results, QM 237A and QM 237B components of the same lot number
should be used.
Mixing and De-aeration
The following procedure should be followed for obtaining optimal performance.
Charge 100 parts, by weight, of QM 237A and 10 parts, by weight, of QM 237B
into a clean, compatible metal or plastic container. Shake the catalyst well before use.
When hand mixing; accurate weighing of components on a suitable scale is essential
for optimal product performance. The volume of the container should be 3-4 times the
volume of the material to be mixed. This allows for expansion of the siloxane material as
it de-gasses.
Mix thoroughly by hand or with mixing equipment while minimizing air
entrapment until a homogeneous mixture is obtained. This will occur when the material
takes on a uniform color with no visible striations. Once mixing * is complete it is
recommended that the material be de-aired 2-3 times by intermittent evacuation for a few
minutes to minimize any imperfections due to bubbles in the cured material. Typically
after releasing the vacuum 2-3 times the mass will collapse on itself at which time the
vacuum should be left on only 2-4 minutes longer.
* Machine mixed material does not normally need to be de-aired.
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Shelf-life and Storage
QM 237A and QM 237B should be stored in their original, sealed containers in an
environment that does not exceed 90F. Under these conditions the expected shelf-life of
the material is 12 months.
Not for Product Specification
The technical data listed herein is provided as a reference only and is not intended
as sales specifications. For sales and technical assistance or for product
recommendations, please call 1-800-852-3147.
Quantum Silicones
8021 Reycan Rd
Richmond, VA 23237
Phone (804) 271-9010 Fax (804) 271-9055
Customer Service (800)852-3147
www.quantumsilicones.com
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