• Thermal Conductivity: 3.5 W/m-K
• Fiberglass reinforced for shear and
tear resistance
• Non-fiberglass option for applications that
require an additional reduction in stress
Features and Benefits
Highly Conformable, Thermally Conductive, Ultra-Low Modulus Material
PROPERTY
Color
Gap Pad
®
3500ULM
IMPERIAL VALUE
Gray
0.020 to 0.125
3.1
1.0
-76 to 392
>5000
V-O
3.5
10
6.0
10
TYPICAL PROPERTIES OF GAP PAD 3500ULM
Fiberglass or
No fiberglass
2
4
METRIC VALUE
Gray
0.508 to 3.175
3.1
-60 to 200
>5000
V-O
3.5
10
0.50
10
6.0
10
Reinforcement Carrier
Inherent Surface Tack
Heat Capacity (J/g-K)
Thickness (inch) / (mm)
Density (Bulk Rubber) (g/cc)
Young's Modulus (psi) / (kPa) (1) (2)
ELECTRICAL
Dielectric Breakdown Voltage (Vac)
Dielectric Constant (1000 Hz) (3)
Continuous Use Temp (°F) / (°C)
Fiberglass or
No fiberglass
2
TEST METHOD
Visual
ASTM D374
ASTM E1269
—
—
ASTM D149
ASTM D150
ASTM D257
U.L. 94
ASTM D5470
20
0.44
30
0.39
ASTM D792
—
—
27.5
1.0
Gap Pad
®
3500ULM (ultra-low modulus) is
an extremely soft gap filling material with a
thermal conductivity of 3.5 W/m-K. The
material offers exceptional thermal
performance at low pressures due to a
unique 3.5 W/m-K filler package and ultra-
low modulus resin formulation. The enhanced
material is well suited for high performance
applications requiring extremely low assembly
stress. Gap Pad
®
3500ULM maintains a
conformable nature that allows for excellent
interfacing and wet-out characteristics,
even to surfaces with high roughness
and/or topography.
Gap Pad
®
3500ULM is offered with and with-
out fiberglass and has higher natural inherent
tack on one side of the material, eliminating
the need for thermally-impeding adhesive
layers. The top side has minimal tack for
ease of handling. Gap Pad
®
3500ULM is
supplied with protective liners on both sides.
140
120
100
80
60
40
20
0
Thickness vs. Thermal Resistance
Gap Pad 3500ULM
Volume Resistivity (Ohm-meter)
Flame Rating
THERMAL
Thermal Conductivity (W/m-K)
THERMAL PERFORMANCE vs. STRAIN
Typical Applications Include:
• Consumer electronics
• Telecommunications
1) Young’s Modulus, calculated using 0.01 in/min. step rate of strain with a sample size of 0.79 inch
2
after 5 minutes of
compression at 10% strain on a 1mm thickness material.
2) Thirty second delay value Shore 000 hardness scale is 70 for 125 mil.
3) Minimum value at 20 mil.
4) The ASTM D5470 test fixture was used. The recorded value includes interfacial thermal resistance. These values are
provided for reference only. Actual application performance is directly related to the surface roughness, flatness and
pressure applied.
Deflection (% strain)
Thermal Impedance (°C-in
2
/W) 0.040" (4)
Configurations Available:
• Sheet form and die-cut parts
GP3500ULM –
0.020 – 02
• ASICs and DSPs
• PC applications
Building a Part Number
– 0816 –
NA
Standard Options
NA = Selected standard option. If not selecting a standard
option, insert company name, drawing number, and
revision level.
0816 = Standard sheet size 8" x 16", or
00 = custom configuration
02 = Natural tack, both sides (Without Fiberglass)
12 = Natural tack, both sides (With Fiberglass)
05 = Non-tack, one side (Without Fiberglass), 7.87" x 15.75"
15 = Non-tack, one side (With Fiberglass), 7.87" x 15.75"
Standard thicknesses available: 0.020"(fiberglass only), 0.040",
0.060", 0.080", 0.100", 0.125"
GP3500ULM = Gap Pad 3500ULM Material without fiberglass
GP3500ULM-G = Gap Pad 3500ULM Material with fiberglass
(GP3500ULM and GP3500ULM-G are also offered in a NT,
non-tack, version)
Section D
Section A
Section B
Resultant Thickness (mils)
.25
.50
.75
1.00 1.25 1.50 1.75 2.00
Thermal Resistance (C-in
2
/W)
Note: To build a part number, visit our website at www.bergquistcompany.com.
Section C
The Bergquist Company -
North American Headquarters
18930 West 78th Street
Chanhassen, MN 55317
Phone: 800-347-4572
Fax: 952-835-0430
The Bergquist Company -
European Headquarters
Netherlands
Phone: 31-35-5380684
Fax: 31-35-5380295
www.bergquistcompany.com
The Bergquist Company -
Asia Headquarters
Hong Kong
Ph: 852-2690-9296
Fax: 852-2690-3408
All statements, technical information and recommendations herein are based on tests we believe to be reliable, and
THE FOLLOWING IS MADE IN LIEU OF ALL WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING THE IMPLIED
WARRANTIES OF MARKETABILITY AND FITNESS FOR PURPOSE. Sellers’ and manufacturers’ only obligation shall be to
replace such quantity of the product proved to be defective. Before using, user shall determine the suitability of the product
for its intended use, and the user assumes all risks and liability whatsoever in connection therewith. NEITHER SELLER NOR
MANUFACTURER SHALL BE LIABLE EITHER IN TORT OR IN CONTRACT FOR ANY LOSS OR DAMAGE, DIRECT,
INCIDENTAL, OR CONSEQUENTIAL, INCLUDING LOSS OF PROFITS OR REVENUE ARISING OUT OF THE USE OR
THE INABILITY TO USE A PRODUCT. No statement, purchase order or recommendations by seller or purchaser not
contained herein shall have any force or effect unless in an agreement signed by the officers of the seller and manufacturer.
PDS_GP_3500ULM_1214
Section E