Tape adhesive types: Silicone vs. Acrylic vs. Rubber

As described in the arti­cle “How Poly­imide Tapes are Made”, tapes are com­posed of two dis­tinct lay­ers, each of which is crit­i­cal to the prop­er­ties of the final prod­uct. The first lay­er is the back­ing mate­r­i­al, and whether this is poly­imide film (the gener­ic veri­son of DuPon­t’s Kap­ton), polyvinyl chlo­ride (PVC), Poly­eth­yl­ene tereph­tha­late (PET), or some oth­er plas­tic, cloth or paper mate­r­i­al, this lay­er is select­ed to pro­vide half of the tape’s final prop­er­ties. The oth­er half is deter­mined by the adhe­sive lay­er applied to this back­ing layer.

The Usual Suspects

Gen­er­al­ly speak­ing, man­u­fac­tur­ers use three dif­fer­ent adhe­sive types in com­bi­na­tion with the back­ing mate­r­i­al to pro­duce a final “tape” prod­uct. Though these adhe­sive types can be sub­di­vid­ed into sub­groups, the main cat­e­gories are as follows:

  1. Sil­i­cone
  2. Acrylic
  3. Rub­ber

Each of these adhe­sive types have advan­tages and dis­ad­van­tages which make them more or less suit­able for par­tic­u­lar appli­ca­tions. Here we will draw the major lines out­lin­ing these differences.

Silicone adhesives

Sil­i­cones have been used to for­mu­late adhe­sive prod­ucts for decades due to their flex­i­bil­i­ty, tem­per­a­ture cycling resis­tance, chem­i­cal resis­tance, and wide range of pos­si­ble mate­r­i­al properties.

Sil­i­cone adhe­sives have the fol­low­ing gen­er­al characteristics:

  • High flex­i­bil­i­ty (low mod­u­lus) at sub-ambi­ent temperature
  • Con­sis­tent per­for­mance over wide tem­per­a­ture range (a rea­son they work so well with Poly­imide Tapes)
  • Excel­lent age­ing and UV resis­tance (a rea­son they work so well in LED applications)
  • High tem­per­a­ture resistance
  • Good resis­tance to polar solvents

Com­pared to acrylic and rub­ber adhe­sives, they are sig­nif­i­cant­ly more expen­sive, but due to their excel­lent high tem­per­a­ture per­for­mance they are very well suit­ed to splic­ing tapes, mask­ing tapes and poly­imide (Kap­ton) tapes.

Acrylic Adhesives

Acrylic adhe­sives can either be water-based (this is also referred to as emul­sion or dis­per­sion) or sol­vent-based. Water-based are slow­er dry­ing com­pared to sol­vent-based sys­tems but gen­er­al­ly sol­vent-based acrylic sys­tems have bet­ter resis­tance to oth­er sol­vents, chem­i­cals and water. Com­par­a­tive­ly, water-based sys­tems are less expen­sive than their sol­vent-based counter parts.

Acrylic adhe­sives are gen­er­al­ly divid­ed into two sub­groups: Pure and Modified

Pure acrylic

Pure acrylic adhe­sives share the fol­low­ing characteristics:

  • Rea­son­able adhe­sion to a wide range of sub­strates (see mod­i­fied acrylics below)
  • Good age­ing, trans­mit­tance and UV resis­tance (a rea­son they are often used in fiberop­tic applications
  • Rea­son­able tem­per­a­ture resis­tance; between sil­i­cones (high resis­tance) and rub­ber (low resistance)

Pure acrylics have a low­er tack (“stick­y­ness when dry” for the lay­man) and less adhe­sion on hard-to-bond plas­tics such as high- and low-den­si­ty poly­eth­yl­ene (HDPE & LDPE) and polypropy­lene (PP) than mod­i­fied acrylic or rub­ber adhe­sives. Pure acrylic adhe­sives are main­ly used on tapes whose appli­ca­tions are bond­ing, seal­ing or sur­face protection.

Modified acrylic

For all intents and pur­pos­es, mod­i­fied acrylics have the same char­ac­ter­is­tics as pure acrylics, but have supe­ri­or adhe­sion to the hard-to-bond-plas­tics men­tioned above. Gen­er­al­ly, these are more expen­sive than pure acrylics and are used for plas­tic bond­ing (includ­ing vinyl and linoleum), lam­i­na­tion and splicing.

Rubber Adhesives

Industrial Rubber TapeJust from look­ing at the roll, it is very hard to tell what type of rub­ber is used on the tape. Look at the fig­ure to the right, and this same pic­ture can be used to describe every type of rub­ber-tape below. The key is to ask the sup­pli­er what type of rub­ber adhe­sive is used. Like acrylics, rub­ber adhe­sives can be divid­ed into two sub­groups: Nat­ur­al and Synthetic

Natural rubber

These adhe­sive have high­er tack (again “stick­y­ness when dry” for the lay­man) than acrylic adhe­sives as well as high­er shear strength but they have lim­it­ed UV resis­tance. These are used in the cheap­est tapes on the mar­ket, but have lim­it­ed appli­ca­tions. Nat­ur­al rub­ber adhe­sives are used in duct tapes, low-tem­per­a­ture mask­ing tapes and sur­face pro­tec­tion tapes (think of the tape you get on your new fridge or stove).

Synthetic rubber

As the name implies, syn­thet­ic rub­ber is “for­mu­lat­ed rub­ber” — think com­ing from the lab, not com­ing from the tree. Syn­thet­ic rub­ber can bro­ken into three sub­groups: Hot-melt, Sol­vent and Butyl rubber.

Hot-melt rubber

Hot-melt is a low-tem­per­a­ture melt­ing plas­tic, which makes this adhe­sive have low tem­per­a­ture resis­tance. It also ages poor­ly (becom­ing brit­tle) and has low UV resis­tance. This rub­ber is used for low- to medi­um-duty car­ton seal­ing, low-tem­per­a­ture splic­ing as well as paper core start­ing applications.

Solvent rubber

Sol­vent-rub­ber based adhe­sives have bet­ter tem­per­a­ture and aging per­for­mance but still poor UV resis­tance. It is used for elec­tri­cal and foam tapes.

Butyl rubber

Butyl rub­ber based tapes have excel­lent UV and aging resis­tance but low­er mechan­i­cal strength. These tapes are used in foam tape appli­ca­tions and con­struc­tion and plumb­ing appli­ca­tions such as pipe joints.

Vis­it www.caplinq.com to learn more about both our Poly­imide films with­out adhe­sive, or our Poly­imide tapes with acrylic or sil­i­cone adhe­sive. You can also con­tact us if you have fur­ther ques­tions on the tem­per­a­ture resis­tance of poly­imide tapes and films.

About Chris Perabo

Chris is an energetic and enthusiastic engineer and entrepreneur. He is always interested in taking highly technical subjects and distilling these to their essence so that even the layman can understand. He loves to get into the technical details of an issue and then understand how it can be useful for specific customers and applications. Chris is currently the Director of Business Development at CAPLINQ.

30 thoughts on “Tape adhesive types: Silicone vs. Acrylic vs. Rubber

  1. How I can iden­ti­fi­cate a rub­ber vs a acrylic adhe­sive, if I don’t have sofisti­cat­ed equipment?
    Thanks

  2. Can you help me in choos­ing the best type of adhe­sive to use in a tape that has to be past­ed on a pow­der coat­ed Alum­ni­um enclo­sure. Oper­at­ing tem­per­a­ture 130Deg c and max volt­age 4kV.
    Thanks.

  3. For pow­der coat­ing appli­ca­tions, as with oth­er tem­po­rary bond­ing appli­ca­tions, there are three key fac­tors to look for:

    1 — Price is impor­tant since it is an inter­me­di­ate step and does not have any val­ue once the process is impor­tant. For these rea­sons, look for a a poly­ester instead of a poly­imide. Poly­ester is good for inter­mit­tent (5 mins or so) at 180°C and are much less expen­sive than a poly­imide film.

    2 — No adhe­sive residue after removal. You did­n’t apply the mask­ing tape only to have it leave an adhe­sive lay­er after removal. For this rea­son, look for a low-adhe­sion bond­ing material. 

    3 — Back­ing thick­ness. For han­dling these mate­ri­als, 1mil thick­ness may (but is not always) be too thin. You want to choose a thick­ness that meets your needs with­out going any thick­er. Extra thick­ness means extra cost that you will just throw away once the process is complete.

    CAPLINQ rec­om­mends three poten­tial mate­ri­als, list­ed in order of rec­om­men­da­tion (links are to the prod­ucts tech­ni­cal datasheets):
    a) PET1.5A-ULA-RL: 1.5‑mil poly­ester film back­ing with an ultra-low-adhe­sion pres­sure sen­si­tive acrylic adhe­sive on a paper release lin­er. It is designed to be a tem­po­rary bond­ing or mask­ing tape for use in a wide range of applications.

    b) PET2SG: Dif­fer­ence with the one above is that it is not on a release lin­er, is 2mil thick (instead of 1.5mil) and uses a sil­i­cone adhe­sive. Designed for appli­ca­tions that need slight­ly high­er adhe­sion and tem­per­a­ture resis­tance and do not want a release liner.

    c) PET1S: Dif­fer­ence with first one is that it is only 1mil thick and uses sil­i­cone and no release liner.

  4. I am look­ing for a mask­ing tape. I need to mask an area for appli­ca­tion of an epoxy — very sen­si­tive to sil­i­cone. The appli­ca­tion is at room tem­per­a­ture so high temp is not required. Which adhe­sive type would make for a bet­ter alter­na­tive — rub­ber or acrylic? I can see advan­tages to both, but would one or the oth­er affect my epoxy like the sil­i­cone does?

  5. Both acrylic adehsive and rub­ber woudl work, but the acrylic adhe­sive will work the best as it will also leave the least residue after removal.

  6. Could you help me list the dis­ad­van­tages for each adhe­sive, specif­i­cal­ly sil­i­cone. Is it real­ly only the price that can be said is bad? Or is it more dif­fi­cult to process or per­haps apply?

    Thanks!

  7. Sil­i­cone adhe­sive is almost always good. The biggest down­side is that sil­i­cones can out­gas under vac­u­um. In space appli­ca­tions, this out­gassing can cause deposits in unwant­ed areas. Pro­cess­ing and appli­ca­tion of sil­i­cone adhe­sives, is nev­er a problem.

  8. I tried to make PVC insulation/ elec­tri­cal tape using hot melt but failed as I could not find a suit­able Hot melt PSA(plasticizer resis­tant). Now I am ging to use liq­uid adhe­sive . Isthere any water based adhe­sive for Elec­tri­cal tape? Or Am I left to choose between sol­vent acrylic and sol­vent rub­bet based adhe­sive? Which one would you recommend?
    Thanks in advance for your help

  9. You real­ly make it appear real­ly easy togeth­er with your pre­sen­ta­tion how­ev­er I find this mat­ter to be real­ly one thing that I
    feel I’d by no means under­stand. It sort of
    feels too com­plex and very large for me.
    I’m look­ing for­ward to your next put up, I will attempt to get the hold of it!

  10. Good morn­ing! I have an indi­vid­ual project in sci­ence and my task is to cre­ate a stronger type of tape. Is there any­thing stronger than silicone?

  11. Can you pro­vide insight on what type of adhe­sive would out­gas the least? This would be for basi­cal­ly a room tem­per­a­ture, and stan­dard atmos­phere con­di­tion. Sounds like Sil­i­cone is the worst, but what would be bet­ter rub­ber vs. acrylic based?

  12. Hi, I am try­ing to fix an elec­tron­ics dial that has a thin film flex­i­ble cov­er­ing skin. This rub­ber “skin ” has torn. Will a sil­i­cone tape be as flex­i­ble as a sil­i­cone adhe­sive? Is sil­i­cone the best choice?
    Thank you,

    Lau­ri

  13. hi could you please tell me what are the major types of acrylic adhe­sives and appli­ca­tions for the same.

  14. I am look­ing for pvc insu­la­tion tape coat­ing line and this post gives me a clue which kind of adhe­sive am going to use

  15. Sir i am Nasar khan from Pak­istan please tell me what types of Adhe­sive tapes is best for the box­es in which we pack the sweet because some time the hands of man who pack­ing the sweet some oil deposit on their hands, due to which every tape do not make a good bond.

  16. We sup­ply the com­plete tapes, not just the adhe­sives them­selves for these tapes. I think that a rub­ber adhe­sive would still be the best for food-relat­ed tapes.

  17. sir
    we are look­ing for rub­ber based glue for mak­ing mask­ing paper tape and sur­face pro­tec­tion tape
    i read your post above and you have rec­om­mend­ed nat­ur­al rub­ber based glue for the same kind­ly can u offer TDS of names of few man­u­fac­tur­ers of the same
    thank­ing you for your help in advance
    best regards
    rajaish

  18. What does “ther­moset­ting” refer to when it is used to describe tape made with ther­moset­ting sil­i­cone pres­sure-sen­si­tive adhesive?
    Best regards,
    Richard

  19. Richard, I don’t know exact­ly. Ther­moset­ting means that its chem­i­cal process can no longer be reversed. In the same of pres­sure sen­si­tive adhe­sive, I sup­posed that over the sil­i­cone hard­ens and it is no longer pos­si­ble to remove with­out adhe­sive residue, but I’m not sure if that actu­al­ly makes it ther­moset­ting. I would argue that the sil­i­cone adhe­sive “dries”, but not nec­es­sar­i­ly ther­mosets after application.

  20. Hi
    Which tape would leave the least residue on a paint­ed wood­en sur­face after remov­ing it 2 or 3 hours after putting it on?

  21. Very inter­est­ing read! I got some hints from your pow­der coat­ing reply!

    I like a sil­i­cone adhe­sive (that will stick to the tape and not on my prod­uct — pow­der coat­ed or paint­ed met­al), that can stick for years on expen­sive prod­ucts and still leaves no residue. I like a low tack.

    I am aware that PET is ide­al, but I like some­thing that is soft­er to man­age curves bet­ter. Are there PVC/Vinyl tapes with sil­i­cone based adhe­sives? I need to plot some shapes with a cutter.

  22. Hi. I just sent you a direct mes­sage but then noticed you are answer­ing ques­tions sim­i­lar to mine here, so I thought I should post it here as well. I’m try­ing to fig­ure out what would be the best tape for cov­er­ing up part of an incan­des­cent bulb (a Philips 45-Watt R20 Dim­ma­ble Spot Light). I would tape it between the base and where it flares out, to lim­it the light that shines through the fix­ture. I’m con­cerned about melt­ing, of course, but also about odor. (This fix­ture is in the kitchen.) What do you think would be best? Thanks so much for any advice you can offer.

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