3M™ Extreme Sealing Tape Alternatives
Included in last month’s shocking news that many widely used 3M™ VHB™ Tapes are no longer available, was the fact that the entire line of 3M Extreme Sealing Tapes are also affected. The use of the Extreme Sealing Tapes: 4411B; 4411G; 4411N; 4412N; 4412G, are not as broad as the affected VHB Tapes. Nonetheless, these sealing tapes fill a critical need for many manufacturers. It is looking ever more likely that all products affected by the Force Majeure announcement will be discontinued. So, once the supply of these products ends, so too will 3M’s entire Extreme Sealing Tape product line. Given the wide use of the industry leading VHB tape products affected, 3M’s focus has been to maintain this business by qualifying available VHB Tapes alternatives. Identifying and qualifying alternatives to the 3M Extreme Sealing Tapes, on the other hand, has been somewhat overlooked. In this article we’ll spend time discussing the critical features of Extreme Sealing Tapes and some ideas for alternatives to test as replacements.
Unlike the VHB Tapes which have direct alternatives available from 3M, Tesa, St. Gobain, Avery, and others, there are no direct product replacements for 3M Extreme Sealing Tapes available on the market. While, we have seen one product from an Asian source claiming to be a replica, no long-term outdoor aging data supported its claims. So, the reality is, Extreme Sealing Tape supply will run out in very short order and there is no clear transition plan. If your company relies on 3M Extreme Sealing Tape, we suggest immediate action to address this challenge. It is critical to assess the scope of your exposure, calculate expected depletion dates, shore up current supplies, and if possible, minimize consumption in the short run to provide ample time to evaluate viable alternatives.
3M Extreme Sealing Tapes are made from the same technology platform as 3M VHB Acrylic Foam Tapes. They have a soft, closed cell acrylic foam adhesive backed by a thin acrylic / ethylene ionomer backing. The ionomer backing is flexible, abrasion resistant, and paintable. On top of the ionomer backing comes a disposable polyester release liner so the product can be made in roll form. Available in either 0.040” or 0.080” thick, these single-sided tapes were developed to address some of the most challenging sealing applications. The tape was designed to withstand several years of severe outdoor climate extremes including harsh heat, humidity, and UV exposure. Used to seal over joints, seams, or penetrations (think rivets or screws), Extreme Sealing Tapes are often used to eliminate the need for caulks and sealants. One common application is to apply the tape as a seal over rivets and the perimeter trim seam on commercial vehicle roofing. Yet, as is common with many 3M technologies, the proliferation of use cases has expanded to a variety of applications, indoors and out.
Fortunately, there are variety of indirect substitutes to meet the needs of many applications. One part polyurethane liquid sealants like the ubiquitous, Sikaflex 221, have been used to seal commercial vehicle roof rivets and trim for decades. 3M’s Polyurethane Sealant 540 is a comparable product that can also be used in these applications. This adhesive technology is, in fact, often used as an indirect replacement for VHB Tapes in panel to frame and roof bow applications common in the commercial vehicle market. They provide a strong, water-tight bond that resists long term outdoor exposure. Yet, the production challenges and mess of liquid sealants is typically the reason to move to tape in the first place.
Though constructed with different technology, Sika, Tesa and Barry make thick single-sided outdoor sealing tapes that deliver many requirements of the Extreme Sealing Tapes. The Sika MultiSeal Plus at 0.037” thick and the Tesa 4641 at 0.026” thick have thin UV stabilized thermoplastic polyolefin (TPO) backings laminated to thick high performance butyl mastics. These products have removable film liners for self-winding and are available in white, black, and gray. With very high green strength, these products bond and seal to a vast array of substrates. Meanwhile the TPO backing is durable, tear resistant, and withstands significant outdoor exposure. Common applications include transportation roof sealing, window moisture barriers, and HVAC duct sealing. Over time we would not expect these products to age as well outdoors as the mastic adhesive may ooze somewhat outside of the tape backing. However, with their application breadth, ability to withstand the elements, and convenience, this category of products should be seen as strong replacement candidates.
Originally developed for the construction trades, the 3M 8777 Sealing Tape and the 3M Ultra Conformable Flashing Tape 3015UC, may also be alternatives for some Extreme Sealing Tape applications. Both products have tough, conformable film backings made from proprietary 3M technology. As sealing tapes used in building construction, they are designed for conformability and to withstand 12 months of UV exposure. Each have super high tack adhesives designed to bond to most materials. They also can be applied in temperatures as low as 0 °F. In contrast to Extreme Sealing Tapes, the 8777 at 0.010” thick and the 3015UC at 0.038” thick are made with thick backings relative to a thinner adhesive layer. The color options are also limited to tan for the 8777 and translucent gray for the 3015C. Both tapes are designed to seal joints around windows and seal wall intrusions around vents, ducts, pipes, and other rough openings. In applications where a conformable, durable sealing tape is required and long-term outdoor exposure is not a concern, one of these innovative tapes may be the ideal match.
Lastly, if none of these options fit your needs, there is always the option of a custom-made sealing tape. Specialty tape converters, like Engineered Materials, specialize in developing and producing custom solutions to meet the specific needs. Converters create custom tapes and parts every day by laminating webs of disparate materials together. They then either slit to width or cut to shape, depending on the requirement. So, there are literally hundreds of custom sealing tape options that can be created without the constraint of large minimums. In fact, Engineered Materials has developed several viable sealing tape alternatives that leverage well tested off the shelf materials.
We do know that selecting and qualifying an alternative to Extreme Sealing Tape will take time. Making your contingency plan and enacting it should be a priority. We’d suggest that you consider your application requirements and test two to three alternative products to ensure that you find the right fit. As discussed, there are several suitable alternatives depending on your specific requirements. To ensure the right solution for your needs, the selection should include unbiased experts you can trust to help guide you through tape selection and evaluation process. An expert will understand all of your specific requirements and find the right solution work for you!
Engineered Materials is a precision industrial tape and specialty materials converter.We are a 3M converter partner, a Sika distributor, and work with hundreds of specialty tape and materials suppliers.Our goal is to create parts to meet your specific needs.We specialize in collaborating with customers to make their products better. Let’s talk about what is possible.