How to Make Adhesive Sticky Again? In my experience, there are several methods to make adhesive sticky again and ensure stickers adhere properly. Before diving into those methods, it’s important to remember a few golden rules.
- Always clean the surface with isopropyl alcohol and let it dry completely before applying the sticker.
- Avoid touching the adhesive while handling the sticker to prevent contamination.
🔥 Heat
Sometimes, applying a little heat can make the adhesive sticky again. You can use a hairdryer or a heat gun, but make sure to keep the temperature under 100°C. If it’s a vehicle or other movable object, putting it out in the sun for a bit can also help, as the heat of the sun does the same job. I used that method on my test of the best adhesive for undermount sink to granite and it worked perfectly.
Heck, I have to admit that this is a less-effective skill to make the adhesive sticky, so keep on reading the “plus version” of “Heating Skill”, which is beneficial to DIYers.
🛠️ Secret Skill: Reactivating & Making It Sticky again
– Adhesive type, Addition of hardeners, Temperature, Thickness, Humidity
No worries. I’ve got you covered!
Let’s get started!
A complete tutorial on bringing life back to old adhesives
Total Time: 3 hours
Gather the adhesive you want to reactivate.
Make sure you know what type of adhesive it is (e.g. epoxy, polyurethane, cyanoacrylate, acrylic, etc.). This will help determine what additives may work best.
Clean and rough up the adhesive surfaces.
Use a solvent to remove any dirt or debris from the adhesive surfaces. Lightly sand or abrade the surfaces to rough them up and provide a “tooth” for the reactivated adhesive to stick to.
Choose your additives.
Based on the adhesive type, choose from plasticizers, tackifiers, solvents, hardeners, or acrylic beads. Get recommendations from the adhesive manufacturer or supplier if possible.
I’ve compiled a comparison table of different additives. You can click here to take a close look.
Melt the adhesive.
Place the adhesive in a container and heat it until it melts thoroughly. For most adhesives, temperatures of 150-200oC should work. You can use a double boiler, oven, heat gun, or other heat source. Be very careful to avoid overheating and fire hazards.
Add the additives to the melted adhesive.
Add the additives in small increments, mixing thoroughly. Start with 5% by weight and gradually increase until you reach the desired stickiness. Test the reactivated adhesive for tack and stickiness as you go.
Apply and clamp the reactivated adhesive.
Apply the reactivated adhesive to one surface. Place the other surface on top and clamp them together tightly. Allow it to cool and harden completely.
Cure the reactivated adhesive.
Allow additional curing time if your reactivated adhesive is epoxy, polyurethane, or another type that requires curing. Follow the recommendation from the adhesive supplier.
Test the bond strength.
Once cured, you can test the strength of the reactivated adhesive bond to ensure it is strong enough for your needs before putting it into use.
Additional treatment.
For some adhesives, post-treatments such as heating to a certain temperature may be needed to fully develop bond strength. Follow recommendations from your adhesive manufacturer.
Estimated Cost: 20 USD
Supply:
- • Adhesive – The adhesive you want to reactivate. Make sure you have the technical data sheet which will specify the adhesive composition and any hardeners or additives originally used.
- • Additives – Such as:
- › Plasticizers (e.g. DOP, DOTP) to soften and extend the adhesive
- › Tackifiers (e.g. rosin esters, terpene phenolics) to increase stickiness
- › Hardener or crosslinker (e.g. polyamine hardener for epoxy) for 2-part adhesives
- › Acrylic beads to improve tack of acrylic adhesives
- › Solvents (e.g. acetone, lacquer thinner) to lower viscosity
Tools:
- • Containers – For melting and mixing the adhesive. Heat-resistant containers made of metal, glass or ceramic are best. Avoid plastics.
- • Double boiler or heater – To gently and evenly heat and melt the adhesive. A double boiler allows using indirect heat. Electric heaters can also be used with care. Use a thermometer to monitor temperature.
- • Mixing tools – Such as stir sticks, spatulas, paddle mixers or mechanical mixers to thoroughly incorporate any additives into the melted adhesive.
- • Applicator – For applying the reactivated adhesive such as brushes, rollers, spray equipment, etc. depending on your needs.
- • Clamps or presses – To clamp the substrates together as the reactivated adhesive dries and cures.
You may need to adjust the steps based on the specific requirements of your adhesive. Be very careful when heating and handling melted adhesives to avoid injury or damage.
Additives Comparison Table
| Plasticizer | A plasticizer is a substance that can soften hard and brittle plastics and make them more flexible and sticky. Common plasticizers include dioctyl phthalate (DOP) and dioctyl terephthalate (DOTP). Adding 5-10% of a plasticizer to the melted adhesive may help reactivate it and make it sticky again. |
| Tackifier | A tackifier is an additive that can increase the stickiness and tack of an adhesive. Common tackifiers include rosin esters, terpene phenolics, and hydrocarbon resins. Adding 5-20% of a tackifier to the melted adhesive can help boost its stickiness. |
| Increase the solvent content | If the adhesive is a solvent-based one, increasing the solvent level in the melted adhesive can make it less viscous and stickier. But be very careful to avoid fire hazards when dealing with solvents. |
| Re-crosslink the adhesive | For 2-part epoxy or polyurethane adhesives, mixing in the hardener component again at the proper ratio can re-crosslink the adhesive and cure it to a sticky state. Make sure to follow the original mixing ratio suggested by the adhesive manufacturer. |
| Plastic acrylic beads | For some pressure-sensitive adhesives such as acrylic adhesives, adding plastic acrylic beads at about 5-10% by weight can improve tack and stickiness. But this may not work for all adhesive types. |
Spray adhesive
Another option is to use a spray-on upholstery glue. Tape out the area where you want to place the stickers, spray a light coat of adhesive, and then position the stickers. Keep in mind that this method might make the stickers more difficult to remove later on.
Homemade adhesive
You can also make your adhesive sticky again by applying a homemade glue solution. Mix a small amount of white glue (like Elmer’s glue) with a few drops of water, and apply it sparingly to the sticker’s back. Be sure to let it dry before attempting to stick it to the desired surface.
You can also use some museum gel to keep things in position. See more here: museum gel vs museum wax
Water-dipped stickers
If you’re working with the kind of stickers that need to be dipped in water before application, clean the surface you want the sticker to stick to first. Dip the sticker in water, wait a bit, and then try to slide the sticker across the paper backing. If it doesn’t slide, wait a bit more and try again. Be cautious not to use too much water, as it can dilute the glue.
I’m Ronald Stevens, a Mechanical Engineer obsessed with adhesives, glue, and all things sticky! My passion began in childhood when I’d always be the one playing with glue during arts and crafts. And I’d spend hours researching and experimenting. Happy reading, and remember: stick with the best, and you’ll never be stuck in a mess!
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