Is Extrudable VHB Tape Right for Your Bonding Needs?
It’s been about 40 years since 3M™ released its first line of VHB™ Tapes, which allowed manufactures to quickly bond materials during the assembly process. Today, they continue to innovate new adhesive tapes and other bonding solutions used by manufacturers in nearly every industry. With these new innovations comes 3M™ VHB™ Extrudable Tape, an extrusion-fed bonding material that provides many benefits for manufacturers who choose to deploy the automated systems to their manufacturing process.
What is Extrudable VHB Tape?
The 3M™ VHB™ Extrudable Tape is a unique adhesive product leveraging the 3M™ VHB™ brand (learn more about VHB™ tapes). While it is branded VHB™, and has many characteristics in common with the VHB™ Acrylic Foam Tape products, it should not be considered a drop-in replacement for the current tape you are using. It’s a high strength pressure sensitive adhesive tape but, unlike acrylic foam tapes, it’s made from a hybrid adhesive material that does not come with a backing. Instead, it’s fed through an automated extrusion machine (using filament spools) and extruded directly onto the desired components.
This extrudable adhesive adheres well to a variety of substrates across various applications, including:
Metal
Glass
Rubber
LSE plastics
Woven and non-woven textiles
Many other hard to bond materials
After application, bond lines can be immediately bonded with another substrate (when hot) or added to a cool tape up to weeks later (when cold).
3M™ VHB™ Extrudable Tapes are tailored for automated assembly. They have reimagined PSA adhesives by providing a faster, simpler, cleaner, and more sustainable solution for adhesive application in the manufacturing process. The material can be applied in various widths, thicknesses, and profiles. This allows for customization in adhesive bonding during assembly.
Why Use Extrudable VHB Tapes?
3M™ VHB™ Extrudable Tapes are efficient, versatile, and productive to use. They can be automated into your assembly process with the right application equipment. The adhesive tape itself has many benefits that include:
Immediate handling strength: this eliminates the need for clamping after application
Fast and easy application: application is automated by an extrusion machine
Reworkable: the material has a stretch release that allows for clean removal. Should it need to be reapplied, it can easily be removed and reused, which results in less material waste.
Most surfaces require little surface preparation
Even distribution reduces stress points by distributing the stress load across the entire surface
The adhesive tape materials can fill gaps without creating wrinkles or voids
The adhesive tape can also form an air and watertight seal
One single adhesive can bond dissimilar substates
Automated application increases manufacturing productivity
Custom bond lines allow for the adhesion of curved and highly complex shapes. Extrusion machines can be programmed to follow any line or path
Not for Everyone: Why VHB Extrudable Tapes Are Not for Every Application
There are many varieties of 3M™ VHB™ tape to meet specific application requirements. While extrudable VHB tapes offer many benefits to manufacturers, they aren’t right for every application.
First, and very importantly, the current material is made from rubber pressure sensitive thermoplastic product. As we have highlighted in previous posts, rubber PSAs are not suitable for outdoor applications or elevated temperatures. Continued exposure to temperatures above 190°F, UV rays, and other outdoor elements can cause the adhesive bond to fail or not meet performance standards. All 3M VHB tapes are made with acrylic foam cores and perform very well outdoors and at temperatures above 300°F.
Next, while one product can be extruded to various thicknesses, the challenge with adhesive application generally is ensuring precise application. Applied in liquid form, VHB Extrudable Tapes, naturally are a challenge in applications where high precise thickness or width are required. So, if high application precision is required, PSA tapes including VHB Tapes are probably a better option.
In certain cases, extrudable VHB tapes may also be an investment that does not make sense for manufacturers to make. In order to use and apply the adhesive tape, robotic extrusion machines must be purchased and deployed on an assembly line, and the application requires high use of the material in order to justify and offset the capital expense.
Finally, in order to optimize bond strength performance, extrudable VHB tapes should be bonded while still warm. Bonds can be made at a later time, after the adhesive has cooled, but adhesion performance will not be as high on the secondary substrate. In contrast, VHB Tapes can be bonded to the secondary substrate at any time after the initial substrate bond without any compromise in adhesion performance.