August, 2018
3
3MTM VHBTM Tape Durability
SummaryThis bulletin addresses the long-term durability of 3M™ VHB™ Tapes and
their ability to perform in certain types of demanding environments. This
will be addressed from a variety of view-points including chemical
composition, resistance to harsh environments, 3M and independent tests
for product durability, and certain applications where 3M™ VHB™ Tape
products have demonstrated excellent ability to perform in demanding
applications. Test results on moisture resistance, UL durability,
accelerated weathering, outdoor weathering, thermal cycling and fatigue
resistance will be discussed.
Composition 3M is a technological leader in acrylate pressure sensitive adhesive (PSA)
technology. 3M™ VHB™ Tapes represent examples of 3M’s proprietary,
state-of-the-art chemistry. The long-term aging resistance lies in the
polymer comprising 3M™ VHB™ Tapes. The chemical bonds that make up
the polymer chains consist of carbon-carbon single bonds that are highly
resistant to energy in the form of heat or ultraviolet light, as well as
chemical attack. In less durable foams or adhesives, such conditions could
lead to cleaving of the polymer backbone and thus a weakening of
mechanical properties. In the case of acrylic adhesives and foams,
however, additional crosslinking is chemically favored over chain scission
(cleavage). This means that, rather than undergoing a process of
decomposition, the acrylate materials will tend to build modulus very
slightly over extended exposures. This translates to a stronger, long lasting
bond.
Durability Testing Temperature Exposure
Because of the demanding and diverse applications users have for
3M™ VHB™ Tapes, durability has always been a key interest in the
performance of these products. One of the first issues for tapes is
retention of tack and adhesion after exposure to elevated
temperatures. Bonds made with 3M™ VHB™ Tapes can tolerate
periodic, short- term exposures to temperatures up to 300°F (150°C)
for most Foam Tapes.
Technical Bulletin
Technical Bulletin
3MTM VHBTM Tape Durability
Accelerated
Weathering
Certain other accelerated aging tests have been conducted in
weatherometers which subject a bond to heat, humidity and concentrated
ultraviolet light exposure. These tests were performed in dynamic shear by
making a stainless-steel overlap bond with 3M™ VHB™ Tape 4950 and
then subjecting the samples to cycling heat, humidity and carbon and arc
lamp exposure. Small samples provided an increased amount of edge
exposure to UV radiation. Figure 1 indicates that the bond strength does not
deteriorate below its original performance level, even after exposure of
7000 hours in the weatherometer under these tests.
200
150
100
50
002000 4000 7000
Figure 1
Weatherometer Testing of 4950 VHB Tape
Hours of Exposure
% Strength Retention
Outdoor Weathering Outdoor weathering decks in Arizona, Florida and other locations around
the world are also used to collect data on the long-term performance of
the 3M™ VHB™ tape family. These tests typically demonstrate about
100% bond strength retention in certain 3M™ VHB™ Tapes after 2 to 5
years aging cycles in the hot, humid climate of Florida, the hot, dry and
very sunny climate of Arizona and the cold to hot extremes of Minnesota
on bonds to aluminum, glass, PVC and painted metal. Figure 2 shows the
constant performance of 3M™ VHB™ Tapes 4950, 4951 and 4952 after 5
years of outdoor aging in Minnesota. Similar results have been obtained in
5 year tests conducted in Japan on 3M™ VHB™ Tapes.
150
100
50
0
Figure 2
VHB™ Tape (5 Year Outdoor Aging, Minnesota)
% Strength Retention: Tensile
0 Yr
1 Yr
2 Yr
5 Yr
4950 4951 4952
VHB™ Tape
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Technical Bulletin
3MTM VHBTM Tape Durability
UL Listing and
Durability Testing
Moisture and
Solvent Resistance
Adhesion tests have been performed on 3M™ VHB™ Tape 4945 bonds of
aluminum to aluminum that were subjected to over 10 years of submersion
in 5% salt water and ordinary tap water. After testing, bright clean
aluminum surfaces were observed underneath the adhesive bond. A
combination of adhesive and cohesive failure modes was observed when
the bond was broken, indicating very high performance levels. Long-term
exposure to high humidity or water submersion can have the effect of
making a polymer more resilient and tolerant of high elongation. A
subsequent lowering in peak force is also measured after many days of
exposure, usually on the order of 40%. This effect is typical as it parallels
the increase in resilience and is the same trend often seen with structural
silicone materials which are also recognized for their durability. Drying of
the 3M™ VHB™ Tape bond, which occurs in a normal environmental cycle,
will show that this effect is reversible and that the bond will return to the
original dry strength.
After splashes or incidental contact with solvents such as fuels, alcohols,
adhesive removers like MEK, and even weak acids or bases, no affect is
measured on the bond performance. Only after continuous submersion in
harsh fuels or solvents is softening of the adhesive/foam experienced.
Note: While 3M™ VHB™ Tape products may withstand occasional contact
with these types of chemicals, continuous exposure is not recommended.
3M™ VHB™ Tape carries UL 746C listings which involve stringent
qualification tests and periodic monitoring by Underwriter’s Laboratories.
Qualification for this listing requires high-strength retention after extended
exposure to high temperatures, humidity, cold, and cyclic conditions. The
table below details 3M™ VHB™ Tapes with the UL 746C listing, and
substrate combinations, as well as the minimum and maximum listed
temperature for each combination.
3M™ VHB™ Tapes
UL746C Listings - File MH 17478
Category QOQW2 Component - Polymeric Adhesive Systems, Electrical Equipment
3M™ VHB™ Tapes/ Temperature Rating
Product Families Substrates Minimum Maximum
Ceramic -35°C 110°C
-35°C 90°C
Aluminum, Galvanized Steel, Stainless Steel, Enameled Steel, Nickel Coated ABS, Glass (with or
without Silane Coating) PVC, Glass/Epoxy, PBT, Polycarbonate, Acrylic/Polyurethane Paint,
Polyester Paint
ABS -35°C 75°C
-35° 90°C
Polycarbonate, Aluminum, Acrylic/
Polyurethane Paint, Polyester Paint
4919F, 4926, 4936,
4936F, 4941, 4941F,
4947F, 4956, 4956F,
4979F
-35°C 90°C
Polycarbonate, Primer 94 Coated Polycarbonate, Aluminum, Acrylic/ Polyurethane Paint,
Galvanized Steel, Polyester Paint, Epoxy Paint, Silane Coated Glass, Uncoated Glass, Stainless
Steel, Enameled Steel, Glass Epoxy, Polybutylene Terephthalate, Nylon, Polyphenelene Ether
(PPE), Acrylic
Rigid PVC, ABS -35°C 75°C
Cellulose Acetate Butyrate -35°C 90°C
5915, 5915P, 5915WF
5925, 5925P, 5925WF,
5930, 5030P, 5930WF,
5952, 5952P, 5952WF,
5962, 5962P, 5962WF
5952, 5952P, 5952WF
Current listings of all 3M VHB Tapes can be found at www.ul.com
Aluminum, Silane Coated Glass -35°C 90°C
PVC, ABS -35°C 75°C
-35°C 90°C
Galvanized Steel, Enameled Steel, Nylon, Polycarbonate, Glass Epoxy, Phenolic, PPE/PS Blend,
PBT, Epoxy Paint, Polyester Paint, Adhesion Promoter 111 Coated Epoxy Paint, Promoter 111
Coated Polyester Paint, Acrylic Urethane Paint, Epoxy/ Polyester Paint
Stainless Steel, Glass, Acrylic -35°C 90°C
PVC, ABS -35°C 75°C
RP16
RP62
RP16, RP25, RP32,
RP45, RP62
4991
Technical Bulletin
3MTM VHBTM Tape Durability
15
10
5
0
Figure 3
MIL STD 883 Exposure Tests
VHB™ Tape F-9460 PC: Polyimide to Aluminum
Peel Adhesion (lbs/inch)
Control: 72 hr RT 1000 @ 90°F/90% RH 1000 T. Shock 1000 @ 150°C
*Thermal shock: -50°C to 150°C hourly
Exposure Time (hours) and Condition
Clarity Since the introduction of the clear 3M™ VHB™ Tapes 4910 and 4905, the
additional issue of long-term clarity and appearance consistency is
commonly asked. Tests have been run for 3000 hours in an accelerated
weathering machine which exposes bonds to high temperatures and
intense ultraviolet (UV) light. To measure clarity, 3 mm float glass plates
were bonded together with 3M™ VHB™ Tape 4910, a 0.040" thick,
transparent foam tape. The percent transmittance was monitored
periodically during the exposure cycle, beginning at 88.2% and finishing at
87.3%. After this long, harsh exposure, only a 1% change in transmittance
was observed. In high humidity environments, however, 3M™ VHB™
Tapes 4910 and 4905 may take on a hazy appearance due to slight
absorption of water molecules. Because the same acrylic polymers are
used throughout 3M™ VHB™ Tape, these results suggest inherent stability
of the whole family.
Thermal ShockThe 3M™ VHB™ Tapes have also performed well in tests, similar to
MILSTD 883, which are commonly used to qualify durable products for the
electronics industry. Under this testing, protocol bonds are subjected to
1000 hours at 150°C, 1000 hours at 85°C and 85% relative humidity, and
1000 hours of thermal shock which cycles hourly from -50°C to 150°C.
Figure 3 shows the excellent performance of the 3M™ VHB™ Adhesive
Transfer Tape F-9460PC in similar testing which involved bonding
polyimide to aluminum. Typically, the bond strength increases with time
due to the high-performance PSA’s more complete wet out of the surfaces.
Fatigue Another durability issue is fatigue resistance. Many types of adhesive
tests are run in a short-term peel, shear or tensile mode where the
sample is broken in a matter of a few seconds. These tests are
convenient for quick characterization of the peak force holding
capability, but do not offer any information about a product’s ability to
tolerate vibration or repetitive strains. Because users have used 3M™
VHB™ Tapes in many applications which require fatigue resistance, such
as trucks or trailers, signs and building panels, a test has been designed
by 3M to characterize this property.
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Application Examples
of Durability
While positive test results are always encouraging, some of the best
examples of 3M™ VHB™ Tape’s durability are existing applications in the
field. 3M™ VHB™ Tapes have been used in applications dating back to
1980.
One of the oldest and most visible applications for the 3M™ VHB™ Foam
Tapes is on ambulance bodies. The aluminum panels comprising the body
of an ambulance can be bonded onto the frame with 3M™ VHB™ Tape.
These applications require durability in harsh conditions on rugged
vehicles that are in service for many years.
Another example of durable applications with excellent performance have
been curtain wall constructions such as the Singapore Treasury Building.
Here the exterior panels are stiffened against wind loads by attaching
unseen stiffeners to the inner surface. These bonds must sustain wind
loads, daily thermal expansion and contraction cycles, and elevated
temperatures. Similar curtain wall and facade applications exist around the
world such as the Walt Disney Concert Hall in Los Angeles, California and
composite ceiling panels in the O’Hare Airport in Chicago, Illinois.
Architectural signs and traffic signs using 3M™ VHB™ Tapes have also
been standing up to constant weathering, buffering winds, and occasional
storms since the early 1980’s.
Technical Bulletin
3MTM VHBTM Tape Durability
106
105
104
103
102
Figure 4
Dynamic Tension Fatigue VHB™ Tape 4950
Load (PSI)
Cycles to Failure
15 25 35 45 55 65
Fatigue
(continued)
In a constant stress machine, tension samples were cyclically loaded over
a range of stresses. The loads were chosen so that bond failures would
occur over a broad range of times. As the load decreases, the specimens
will survive more and more cycles; this trend can be plotted semi-log as in
Figure 4. The semi-log plot yields a straight line which can be used to help
predict longer term performance at lower stresses not practical to
measure. Given a product lifetime estimate for cyclic loading, the data can
be extrapolated to estimate the maximum tolerable design stress. For
3M™ VHB™ Tapes , this is typically about 20 psi for one million cycles of
full reversal loading. These tapes tend to perform well in these types of
tests because of their inherent viscoelasticity. The acrylic foam and
adhesive absorb energy and relax stresses internally, thus helping protect
the adhesive bond on the substrate.
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Technical Bulletin
3MTM VHBTM Tape Durability
3
Industrial Adhesives and Tapes Division
3M Center, Building 225-3S-06
St. Paul, MN 55144-1000
800-362-3550 • 877-369-2923 (Fax)
www.3M.com/vhb
3M and VHB are trademarks of 3M
Company. Printed in U.S.A.
©3M 2018 70-0709-3862-9 (8/18)
Recycle, Neg
3M warrants for 24 months from the date of manufacture that 3M™ VHB™ Tape will be free of defects in material
and manufacture. 3M MAKES NO OTHER WARRANTIES OR CONDITIONS, EXPRESS OR IMPLIED,
INCLUDING, BUT NOT LIMITED TO, ANY IMPLIED WARRANTY OR CONDITION OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE, OR ARISING OUT OF A COURSE OF DEALING, CUSTOM, OR
USAGE OF TRADE. This warranty does not cover damage resulting from the use or inability to use 3M™ VHB™
Tape due to misuse, workmanship in application, or application or storage not in accordance with 3M
recommended procedures (except to the extent 3M approves and issues a specific application warranty, for which
the customer must apply, receive 3M approval, and meet all applicable warranty and process requirements, the
additional details, terms, and conditions of which are available from 3M). If a 3M product does not conform to this
warranty, then the sole and exclusive remedy is, at 3M’s option, replacement of the 3M product or refund of the
purchase price.
Warranty, Limited
Remedy, and
Disclaimer
Application
Examples of
Durability
(continued)
Another example of 3M™ VHB™ Tape durability came from testing at the
Bendix Automotive Proving Grounds in Indiana. A full size semi-truck with
sleeper cab was constructed with all exterior panels and doors taped to an
underlying frame with 3M™ VHB™ Tape 4950. After approximately 300,000
simulated miles on the harsh Durability Track, the 3M™ VHB™ Tape bonds
remained completely intact. This is particularly impressive as some
mechanically joined and welded parts experienced failures and required repairs
for the test to continue.
One of the most demanding applications for 3M™ VHB™ Tape has been on
aircraft exteriors. Several commercial aircraft models have incorporated
stainless steel anti-chafing strips bonded to the aluminum wing flaps. These
panels help prevent abrasion and chafing between the flap and underside of the
wing during movement of the flaps for take offs, landings, and in-flight
vibration. 3M™ VHB™ Adhesive Transfer Tape 9473 continues to be a means
for bonding these panels into place. This application has been in use since 1984.
Durability is particularly key in this application since the bond can be subjected
to high skin temperatures in direct sunlight on the ground and -65°F (-54°C) at
high altitudes. In addition, this cycle can be repeated several times per day.
The technical information, guidance, and other statements contained in this document or otherwise provided by 3M
are based upon records, tests, or experience that 3M believes to be reliable, but the accuracy, completeness, and
representative nature of such information is not guaranteed. Such information is intended for people with
knowledge and technical skills sufficient to assess and apply their own informed judgment to the information. No
license under any 3M or third party intellectual property rights is granted or implied with this information.
Technical
Information
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Failure to properly evaluate, select, and use a 3M product and appropriate safety products, or to meet all
applicable safety regulations, may result in injury, sickness, death, and/or harm to property.
Product Selection
and Use
MSDS: 3M has not prepared a MSDS for these products which are not subject to the MSDS requirements of the
Occupational Safety and Health Administration’s Hazard Communication Standard, 29 C.F.R.1910.1200(b)(6)(v).
When used under reasonable conditions or in accordance with the 3M directions for use, these products should
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This Industrial Adhesives and Tapes Division product was manufactured under a 3M quality system registered to ISO 9001 standards.
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