Low surface energy (LSE) plastics are favorites of design engineers, but do any adhesives bond to them?

Are there any adhesives that work with low surface energy (LSE) plastics? While LSE plastics provide low cost, excellent physical properties, durability, flexibility, and good resistance to temperature extremes and moisture, they are not easily bonded with traditional adhesives. Are there any adhesives that will work cost-effectively with these materials, including polyethylene, polypropylene, EVA, PVA, and others?

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  • Jeremy Cooler

    Jeremy Cooler

    Technical Specialist Bonding, Joining & Sealing Business Unit FABRICO To read Jeremy's opening, click here
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    1. LSE plastics are well-liked by design engineers for their versatility. They are light weight, durable, flexible, and typically lower cost than metals or other materials. Yet, their non-stick characteristics make them hard to bond. For many design engineers, working with these materials may mean expensive and time-consuming use of mechanical fasteners, ultrasonic welding or elaborate pre-treating. New acrylic and cyanoacrylate adhesives that provide strong bonds with LSE plastics are changing that. New liquid adhesives and pressure-sensitive adhesive (PSA) tapes are being used with LSE plastics in automotive, recreational and sport vehicles, electronics, appliances, aerospace, and medical applications. When working with LSE plastics it’s important to select the right adhesive for the application and the material.

  • Joe Musca

    Joe Musca

    Converter Markets Account Representative 3M To read Joe's opening, click here
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    1. Engineers working with LSE plastics want to use adhesives for a number of good reasons: to distribute loads evenly across a joint; resist stress caused by flexing, vibration, and impact; fill surface gaps to seal as well as bond; provide invisible, aesthetically pleasing bonds; eliminate mechanical fasteners; and reduce weight. Using adhesives with LSE plastics is all about good wetting by the adhesive, which creates strong adhesion/good bonding. Acrylic liquid adhesives and tapes, cyanoacrylates, light-cure acrylics, and light-cure cyanoacrylates are all possible adhesive technologies that work well with LSE plastics.

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22 Responses Below

  1. Hey, thanks for the blog. Keep writing.

    by Rocky on January 9, 2012 at: 12:34 am
  2. Very neat blog article.Really looking forward to read more. Really Cool.

    by Mathias Gammage on January 8, 2012 at: 2:40 pm
  3. Great post, you have pointed out some superb points, I too think this is a very excellent website.

    by Erinn Bronaugh on January 3, 2012 at: 4:56 pm
  4. Is plasma cleaning an effective method of preparing the LSE plastic surface for adhesion?

    by Kurt Annen on December 1, 2011 at: 10:34 am
  5. Loc-Tite makes a low energy plastic primer, I believe #770 that in conjunction with their CA adhesives makes very rugged bonds. I successfully glued together a polyolefin (polypropylene?) internal motor fan that had been broken into several pieces and it has been in service for several years now.

    by Dale Dell'Ario on November 4, 2011 at: 3:45 pm
    • The 770 is an excellent primer used in conjunction with one of Loctite’s several CA’s designed for LSE materials. The 770 also acts as an activator to increase the speed of handling strength. A word of caution, however, if you need high peel strength out of your bond I would suggest at minimum evaluating another primer. If you need any gap filling properties and want to use a gel CA the 770 does not deliver the same performance. Please feel free to contact me @ jcooler@fabrico.com if I can help you with any adhesive questions.

      by Jeremy Cooler on November 8, 2011 at: 9:18 am
  6. How much of an effect do temperature and humidity and their changes have after the adhesive has cured or settled?

    by francisco molina on November 3, 2011 at: 5:36 pm
    • Humidity is generally not a factor after the adhesive has cured. Most adhesives designed for low surface energy substrates have temperature resistance higher than the plastic itself. When the adhesive is bonding dissimilar substrates (i.e. polyethylene and aluminum), there may be some challenges due to different coefficients of thermal expansion, causing the bond to undergo additional strain or fracture. Often the integrity of the low surface energy substrate is compromised before the adhesive itself fails.

      by Craig McClenachan on November 4, 2011 at: 9:38 am
  7. Is there an adhesive that bonds polyethylene sheets and is tolerant of sunlight and rain?

    by Jim Wilke on November 3, 2011 at: 4:29 pm
    • Jim,

      There are adhesives that can bond your Polyethylene sheets and withstand UV and rain. In order to get you in the right direction, I would need a better understanding of the actual application. What it is, how much UV is it exposed to? Is this item living in the Arizona desert for 20 years or a rooftop in Seattle? Maybe its both. Is the part going to be exposed to Dynamic forces, such as on top of an RV or experience heavy wind loads on the roof of a building? The answers to these questions will really help us steer you into the direction of the best adhesive to suit your application. Please feel free to e-mail me directly at jcooler@fabrico.com or click on the ask an engineer button and we can narrow in on a solution suited to your particular application.

      by Jeremy Cooler on November 4, 2011 at: 11:52 am
  8. Do the suggested adhesives for low surface energy plastics eat away, warp, or compromise the plastic in any way?

    by Dan Seyler on October 25, 2011 at: 3:38 pm
    • The structural adhesive systems for low surface energy plastics do not compromise the plastics themselves, they have the ability to “wet- out” these hard to stick to materials

      by jeremy cooler on October 31, 2011 at: 8:34 pm
  9. Are there adhesives that can help me bond LSE plastics to metals or other surfaces?

    by Aimee on October 25, 2011 at: 2:29 pm
    • The answer to your question is yes!! Metals for the most part (untreated or non painted), have a “high surface energy” (easy to stick to). Typically the adhesives designed for the LSE materials will also form a strong bond to metal. In these situations, where multiple materials are be being bonded, we match up an adhesive suited to the harder to bond to material. If you need more specific information involving substrates and product suggestions, please feel free to post or click on the ask an engineer button.

      by jeremy cooler on October 27, 2011 at: 11:42 am
    • I’ve evaluated various adhesives for metal label application on LLDPE transit cases over the past year. The best results I’ve found so far have come from the 3M line of tapes utilizing their 300LSE adhesive. Try greater adhesive thickness on rougher surfaces (9472LE vs 9471LE). The VHB tapes designed for LSE surfaces (4932 and 4952) also work well.

      by Thad Ayres on December 1, 2011 at: 10:46 am
    • We have had good success with the 3M adhesives Thad mentions on LDPE and HDPE.

      by Mark White on December 12, 2011 at: 5:04 pm
  10. Do I need to prime or scratch the surface of the LSE plastic berfore using an adhesive?

    by Greg Buser on October 25, 2011 at: 2:26 pm
    • Abrading the surface and priming are two ways to raise the level of adhesion to a hard to stick to plastic. Abrading creates small crevices in the surface, which creates more surface area for the adhesive to adhere to. LSE primers actually etch or bond to the plastic. The new surface the primer creates has a “higher surface energy” (easier to stick to) and can help create a stronger bond. When abrading you need to be mindful that you do not create too deep a scratch. If the adhesive cannot adequately “wet out” or entirely fill the void you can actually create a weaker bond than if you did not abrade the surface. Typically, a light going over with a low grit Scotch Brite pad will be sufficient, but neither of these methods are rule of thumb. There are some new adhesives that do not require either of these steps and some that benefit from one or both. It really depends on the specific substrate and the specific application. Feel free to click on our ask an engineer button and we can discuss more in detail and find the right adhesive and the right process for your application.

      by jeremy cooler on October 26, 2011 at: 4:01 pm
      • We found that applying a 10-second long plasma treatment of the bonding surface raises the surface energy above 50 dyne even for materials notoriously hard to bond (PTFE, Teflon, etc.)

        by Cristian Spanu on December 1, 2011 at: 10:20 am
      • Jeremy, Spot on. Primer 94 is our go to Primer and can be used to promote adhesion of 3M tapes to surfaces such polyethylene, polypropylene, ABS, PET/PBT blends, concrete, wood, glass, metal and painted metal surfaces. Adhesion Promoter 111 is an isopropyl alcohol based solution used to promote better and faster adhesion of 3M VHB Tapes to various surfaces including bare metals, galvanized steel, and painted surfaces. Since surfaces and paint formulations vary considerably, each application should be verified through testing.
        In the end, always remember after abrading or priming, pressure is a requirement for ultimate adhesion too.

        by Joe Musca on January 27, 2012 at: 3:51 pm
  11. Will adhesives used with LSE plastics cause cracking along the plastic surface?

    by James on October 25, 2011 at: 1:23 pm
    • Typically, adhesives do not compromise the integrity of substrates. Most adhesives designed for low surface energy substrates are designed to avoid cracking, but there may still be some factors that should be considered when testing and selecting adhesives for a specific application.

      by Craig McClenachan on November 4, 2011 at: 10:12 am