L-3540 REV 1 A/B Page 1 of 2 Date: 11/01/2022
For more information call BJB Enterprises, Inc. (714) 734-8450 Fax (714) 734-8929
www.bjbenterprises.com
L-3540 REV 1 A/B
40 SHORE A POLYURETHANE ELASTOMER
BJB s L Series , with its 20 to 35 minute work time, is perfect for manufacturing larger or more complex parts and molds. The
L-3540 is a 40 Shore A material offering exceptional physical properties. You ll find the 1:1 ratio to be extremely convenient
whether you re hand mixing or cartridge-dispensing with our CPE handheld dispense equipment. For faster work times consider
BJB s F-1 or M Series of urethane elastomers.
RoHS/REACH compliant Vibration Dampening Industrial Rollers
Plaster and Concrete Molds Over Molding Strain Reliefs
PHYSICAL PROPERTIES TEST METHOD ELEVATED TEMPERATURE CURE*
Hardness, Shore A ASTM D2240-04e1 40 5
Density (g/cc) ASTM D792-00 1.035
Cubic Inches per Pound N/A 26.92
Color/Appearance Visual Clear Amber
Tensile Strength (psi) ASTM D412-98a(2002)e1 960
Tensile Modulus (psi) ASTM D412-98a(2002)e1 175
Elongation (%) ASTM D412-98a(2002)e1 1,100
Tear Strength (pli) ASTM D624-00e1 120
Shrinkage (in/in) linear ASTM D2566 @ 1 depth 0.0010
Dielectric Constant, 1 MHz ASTM D150-87 5.198
Dissipation Factor, 1 MHz ASTM D150-87 0.0512
*Note: Reported physical properties are based on test specimens cured 1-3 hours at room temperature then 16 hours at 160 F (71 C).
Shrink test specimens are cured for 24 hours at room temperature and then 16 hours at 160 F (71 C).
HANDLING PROPERTIES Part A Part B
Mix Ratio by weight 100 100
Mix Ratio by volume 100 100
Specific Gravity @ 77 F (25 C) 1.028 1.032
Color Pale Yellow Amber
Viscosity (cps) @ 77 F (25 C) Brookfield 1,475 1,350
Mixed Viscosity (cps) @ 77 F (25 C) Brookfield 1,600
Work Time, 100g mass @ 77 F (25 C) 25 30 minutes
Gel Time 45 50 minutes
Demold Time @ 77 F (25 C) 8 14 hours
Properties above are typical and not for specifications.
SHORE A POLYURETHANES
Dedicated to QUALITY, SERVICE, SAFETY, and INNOVATION
An ISO-9001 Certified company
L-3540 REV 1 A/B Page 2 of 2 Date: 11/01/2022
For more information call BJB Enterprises, Inc. (714) 734-8450 Fax (714) 734-8929
NON-WARRANTY “Except for a warranty that materials substantially comply with the data presented in Manufacturer’s latest bulletin describing the product (the basis for this substantial
compliance is to be determined by the standard quality control tests generally performed by Manufacturer), all materials are sold “AS IS” and without any warranty express or implied as
to merchantability, fitness for a particular purpose, patent, trademark or copyright infringement, or as to any other matter. In no event shall Manufacturer’s liability for damages exceed
Manufacturer’s sale price of the particular quantity with respect to which damages are claimed.”
CURE SCHEDULE/HEAT CURING:
Most of the physical properties can be achieved in 5-7 days at 77 F (25 C). You may use your own post-cure schedule but the physical
properties may vary from BJB s cure schedule of 1-3 hours at 77 F (25 C) followed by 16 hours at 160 F (71 C). Do not exceed
curing temperature of 200 F (93 C).
PREPARATION AND RELEASING:
When L-3540 A/B is used to produce molds or parts from plaster, wood or other porous substrates, we would first recommend that
they be sealed. Release agents may then be applied over the sealed surface.
NOTE:
Prolonged direct exposure to sunlight can affect the surface of this product. Cover molds or other products when storing outdoors.
The cure may be inhibited if cast against a relatively new tin catalyzed (condensation cure) silicone RTV.
ACCESSORIES:
BJB offers silicone RTV mold making materials along with a wide range of accessory items. These include de-airing agents, pigments,
mold releases, and Jiffy
Mixers. Visit BJB s website at www.bjbenterprises.com or consult a BJB representative for more
information.
STORAGE:
Store ambient temperatures, 65-80 F (18-27 C). Unopened containers will have a shelf life of 6 months from date of shipment when
properly stored at recommended temperatures. Purge opened containers with dry nitrogen before re-sealing.
PACKAGING Part A Part B Cubic Inches per Kit
Quart Kits 2 lbs. 2 lbs. 108
Gallon Kits 8 lbs. 8 lbs. 431
5-Gallon Kits 40 lbs. 40 lbs. 2,154
SAFETY PRECAUTIONS:
Use in a well-ventilated area. Avoid contact with skin using protective gloves and protective clothing. Repeated or prolonged contact
on the skin may cause an allergic reaction. Eye protection is extremely important. Always use approved safety glasses or goggles
when handling this product.
IF CONTACT OCCURS:
Skin: Immediately wash with soap and water. Remove contaminated clothing and launder before reuse. It is not recommended
to remove resin from skin with solvents. Solvents only increase contact and dry skin. Seek qualified medical attention
if allergic reactions occur.
Eyes: Immediately flush with water for at least 15 minutes. Call a physician.
Ingestion: If swallowed, call a physician immediately. Remove stomach contents by gastric suction or induce vomiting only as
directed by medical personnel. Never give anything by mouth to an unconscious person.
Refer to the Material Safety Data Sheet before using this product.
WARNING: This product can expose you to chemicals including Toluene diisocyanate, which is known to the State of
California to cause cancer. For more information, go to www.P65Warnings.ca.gov.
Handling Guide