VHB Tapes are exceptionally strong bonding tapes, and provide an excellent alternative to mechanical fasteners, screws, rivets, and welds. They work through the bonding tape permanently attaching one substrate to another substrate, and distributes the stress load across the joint. After the materials are joined, the tape creates an exceptional weld.
Resists moisture, UV Light, and temperature cycles
Foamed acrylic tapes are formulated from acrylic copolymers and monomers to produce a self adhesive viscoelastic foam, which is a high density, closed cell foam, cured by using U.V. light. There are no solvents used in the manufacturing process.
The foam is produced by coating on a ‘knife over roller’ coating head. The syrup is then coated onto a high grade polyester process liner. Two process liners are used in the manufacturing, with the gap between the bottom and the top liner determining the thickness of the foam.
The tape is available in thicknesses between 0.25mm (10mil) and 3mm (120mil). Tolerance on the thickness of the foam is ± 50 micron.
VHB acrylic foams are available in White, Grey and Clear grades. The white and grey grades have glass microspheres as a filler that gives exceptional cohesive strength to the foam. The clear grade does not contain microspheres.
The density of the white and grey grades is approximately 800kg/m3 (1348 lb/yd3), and the clear is 1000kg/m3 (1686 lb/yd3).
Standard liners are 135 micron red polyethylene and 120 gsm white PE coated paper.
Application Performance is dependent upon:
VHB bonds to a wide variety of surfaces.
The viscoelastic properties of VHB allows the adhesive to flow into the microscopic surface of materials. The adhesive bond is very strong when there is good ‘wet out’, maximum adhesive contact under pressure with the substrates to be bonded.
Abrading the surface to be bonded actually improves the strength of the bond. This creates a rough surface for a greater area for the adhesive to key into.
The elastic characteristics of the foam give it very good internal cohesive strength to support loads in both static and dynamic shear. It also gives the foam very good peel adhesion strength
The tape is soft and very flexible which means it has great conformability.
The foam also has very good elasticity due to the high internal cohesive strength of the foam.
The tape will radius well, (go around curves).
THE THICKNESS OF TAPE SELECTED SHOULD DEPEND ON THE FOLLOWING FACTORS:
This depends on a number of factors:
As a general rule 645mm2 (1 in2) of tape should be used to hold 1kg (2.2 lbs) in a static situation. This will vary from application to application.
There is a safety factor built into this equation. All users should test the tape in their own application thoroughly.
VHB foamed acrylic tape will hold substantial loads, but a safety factor is important in critical structural application
Q. TEMPERATURE RANGE?
Q. DURABILITY – HOW LONG WILL IT LAST?
Answer: Acrylic is a very durable chemical material
Q. HOW MUCH TAPE SHOULD YOU USE?
Q. RESISTANCE TO WATER / HUMIDITY / SOLVENTS?
EXCELLENT WATER / HUMIDITY RESISTANCE
EXCELLENT SOLVENT RESISTANCE
Q. HOW DO YOU REMOVE TAPE?
CUT OFF USING SOAP AS LUBRICANT
WRONG TAPE FOR SURFACE
Watch especially for low surface energy plastics and potentially difficult to adhere to paint surfaces
Optimum application temperature is 21°C (70°F) to 38°C (100°F) temperature must be minimum for most PSA’s. At colder temperatures, immediate bond strength is lower and bond build is slower.
High performance adhesives (VHB), are severely affected affected by surface contamination.
Clean all surfaces with 50:50 mix of isopropyl alcohol and water (works on most surfaces, non hazardous).
Oily surfaces clean with heptane or suitable solvent. Best to follow with IPA – water
Surface abrasion can provide improved bond strength to many surfaces, can speed up bond build.
TAPE TOO THIN
Thin tapes cannot make adequate surface contact with rigid materials.
Semi-flexible materials with memory need thicker tape to distribute stress.
TESTED BEFORE BOND BUILDS
Typically full bond is not reached until 72 hours. (50% at 20 minutes, 90% at 24 hours)
Abrasion speeds bond build
Cold temperature delays bond build