A Guide to the Best Glues for Plastic
Left to right: Z-Poxy 5 Minute Formula, Testors Cement for Plastic Models, Duco Cement, Devcon Home Plastic Welder, E-6000
When working with plastic and glue, not all types of glue are created equal. There are many things to consider in order to find the best glue for plastic in any of your projects. We’ll cover the different types of plastic, the different types of plastic glue and how to glue plastic for the best results.
Types of Plastic
First off, it’s best to know what type of plastic you’re using in order to choose the best plastic glue for your project. Some plastics and glue don’t work well with each other. In order to find out what kind of plastic you have, simply find the symbol with the three arrows and number in the center somewhere on the item (usually on the bottom). No symbol? No problem! We’ll use our best guess as to what type of plastic it is using the descriptions below.
|Type of Plastic (Recycle Number)||Common Examples||Compatible Glue(s)|
|Polyethylene Terephthalate PET or PETE (1)||Plastic bags, plastic bottles, usually softer plastic||3M Scotch-Weld, 3M High Strength 90 spray adhesive|
|High Density Polyethylene HDPE (2)||Detergent bottles, milk jugs, toys, usually hard plastic||Devcon Plastic Welder, Plastic Weld Epoxy|
|Polyvinyl Chloride PVC (3)||Plumbing pipes, toys, window frames, garden hoses, beach balls, imitation leather||Devcon Plastic Welder, Duco Cement, E-6000|
|Low Density Polyethylene LDPE (4)||Outdoor furniture, shower curtains, squeezable plastic bottles, floor tiles||Plasti-Zap, Hot Stuff, Devcon Plastic Welder (for hard plastic only)|
|Polypropylene PP (5)||Bottle caps, straws, yogurt containers, appliances, buckets, pails||Z-poxy, Devcon Plastic Weld|
|Polystyrene (aka Styrene) PS (6)||Foam peanuts, disposable cups, plates, egg cartons, CD cases, plastic model kits||Testors Plastic Cement, Devcon Plastic Welder, Duco Cement, Micro Weld, Plastruct Bondene, Plasti-Zap|
|Acrylonitrile Butadiene Styrene ABS (7)||Toys such as Legos||Duco Cement, Plastruct Bondene, Devcon Plastic Welder, Plasti-Zap|
|Acrylic||Clear plastic frames||Plastruct Plastic Weld, Devcon Plastic Welder, Duco Cement, E-6000|
Unmarked items such as cheap toys, brittle, clear plastics are often made of polystyrene, whereas tough, hard plastics such as bottles, buckets and crates will most likely be polyethylene or polypropylene. Other plastics also may include acrylic which is a clear, durable plastic also known as plexiglass.
Polyethylene Terephthalate (PET or PETE) Recycle symbol: 1 This kind of plastic is used to make plastic bags and disposable plastic bottles. It is lightweight and often used to make packaging, storage containers and bottles for holding glue (as the glue won’t stick to it!). It has a low surface energy and that makes it a fairly non-stick surface (and therefore hard to glue). Glues to use with this type of plastic:3M Scotch-Weld, 3M High Strength 90 spray adhesive
High Density Polyethylene (HDPE) Recycle symbol: 2 This kind of plastic is used for detergent bottles and milk jugs, buckets and crates. It is thick, heavyweight and durable. Glues to use with this type of plastic: Devcon Plastic Welder**
Polyvinyl Chloride (PVC) Recycle symbol: 3 PVC is a soft and flexible plastic used to make clear plastic cooking oil bottles, food wrapping, teething rings, toys, plastic pipes and plumbing parts. Glues to use with this type of plastic: Devcon Plastic Welder, Duco Cement, E-6000, Z-poxy
Low Density Polyethylene (LDPE) Recycle symbol: 4 LDPE is often found in dry cleaner garment bags, shrink wraps, squeezable bottles, packaged bread bags and some clothing and furniture. Glues to use with this type of plastic: Plasti-zap, Hot Stuff, Devcon Plastic Welder (for hard plastic only)
Polypropylene (PP) Recycle symbol: 5 Common items made from polypropylene include floating rope, car batteries, pill bottles, pitchers, model aircraft, chairs, cups, reusable containers, bottle caps and drinking straws. You can use two part epoxy glue or a hot-glue gun if the objects you need to glue are solid and won’t be bent or flexed too much. Plastic welders are also very good for joining polypropylene to itself. Glues to use with this type of plastic: It is difficult to glue polypropylene to itself or other plastics. You can use two part epoxy glue (such as Z-poxy) when gluing polypropylene to other surfaces or plastic welders (such as Devcon Plastic Weld) when gluing polypropylene to itself.
Polystyrene (also referred to as Styrene) (PS) Recycle symbol: 6 Also known as styrene, polystyrene is often used to make disposable drinking cups, egg cartons, disposable cutlery, food containers, packing peanuts, and is common in plastic model kits. Glues to use with this type of plastic: It is helpful to use plastic cement (like Testor’s Cement for Plastic Models) when bonding polystyrene to itself; use cyanoacrylate (such as Plasti-zap or Hot Stuff) or epoxy (Z-poxy) when gluing two different surfaces. Other compatible glues include Devcon Plastic Welder, Duco Cement, Micro Weld, Plastruct Bondene (when gluing polystyrene to itself).
Acrylonitrile Butadiene Styrene (ABS) Recycle symbol: 7 Some common items made of ABS plastic are black plumbing pipes, and toys such as Legos. Glues to use with this type of plastic: Duco Cement, Plastruct Bondene, Devcon Plastic Welder
Acrylic Also known as “Plexiglass,” this type of plastic is often clear and is used for clear frames, shelves or containers, aquariums and tail lights. Glues to use with this type of plastic: Plastruct Plastic Weld, Devcon Plastic Welder, Duco Cement, E-6000
Best Types of Glue for Plastic
There are many different brands that make many different types of plastic glue. Here we will look at a few different brands and also look over the types of glue in general that are best for each type of plastic. Not all plastic glue will work with all types of plastic. Be sure to check the type of plastic you are working with in order to find the best plastic glue for your project. If working with several different types of plastic and surfaces, you may need more than one type of glue. Some glues will work well with several types of plastic while some are only good for one type of plastic. And still other glue may be incompatible with certain types of plastic, so be aware of that as well. As with all products, it is recommended to read and follow the directions and warnings on the packaging.
|Glue Brand (type)||Best for Plastic Types||Notes|
|Devcon (epoxy)||PVC, polystyrene, ABS, acrylic, hard plastics||Set time: 10-15 min Cure time: 24 hrs|
|Duco Cement (multi purpose)||ABS, PVC, polystyrene; NOT for polyethylene, polypropylene or styrofoam||Set time: 5 min Handling time: 1 hr Cure time: 16 hrs Dishwasher safe Not for use on items that will come into contact with food|
|E-6000 (multi purpose)||Acrylic, PVC, vinyl; NOT for styrofoam, polystyrene, polyethylene, or polypropylene||Set time: 20 mins Cure time: 24 hrs Washer/dryer safe, photo safe|
|Plasti-Zap (cyanoacrylate)||Polystyrene, ABS plastic, vinyl; NOT for clear acrylic||Set time: 5-20 seconds Cure time: 24 hrs|
|Plastruct Plastic Weld (model cement)||Acrylic, ABS, polystyrene||Set time: 1-2 min Cure time: 24 hrs Works best at bonding dissimilar surfaces Use Plastruct Bondene for bonding similar surfaces (ie polystyrene to polystyrene)|
|Testors Plastic Cement (model cement)||Polystyrene||Cure time: 24 hrs|
|Z-Poxy (epoxy)||Polyethylene, PVC, polypropylene, ABS, NOT for polystyrene||Set time: 5 min Handling time: 30 min Cure time: 16 hrs Excellent for gap-filling, shock and solvent resistant|
Note: handling and cure times may vary due to weather conditions, humidity, etc.
This type of glue works best when the two items to be glued are tightly joined and there are no large gaps. It is not ideal for outdoor or mechanical use nor for use on clear acrylic (due to discoloration) or soft plastics. This glue works great for bonding two dissimilar materials. It comes in three types of viscosity: Thick (gap-filling), medium, and ultra-thin. The thick formula can be used on two pieces that don’t fit tightly together, although it might take longer than normal for the two items to stick together. Medium is the easiest to work with, as it doesn’t run like the thin variety and bonds quickly. Ultra-thin is harder to work with and is more watery in consistency so you will need a special brush or applicator. The benefit is that it bonds very quick. Overall, rough surfaces stick better than smooth ones, so a light sanding is recommended.
Plasti-zap is a cyanoacrylate adhesive, aka “super glue”
Some cements (like Testors Cement for Plastic Models) are only used for rigid polystyrene plastic, aka “styrene”, which is commonly used in plastic model kits. Others cements, however, can be used on a variety of materials such as ABS, styrene, and acrylic (such as Plastruct Plastic Weld or Plastruct Bondene). This glue works by dissolving the surfaces of the plastic and melding them together. The advantage to using this type of glue is that it forms a very strong bond. The disadvantage is that if too much is used, it can dissolve through the plastic as well as damaging any surface details. It should not be used in holes or cavities that are not exposed to air because it will slowly dissolve the surrounding plastic.
It is also available in different viscosities: thick, medium and ultra-thin (or liquid poly cement). The thicker variety comes in metal tubes and has the consistency more like toothpaste. One advantage is that it dries slower allowing for more time to make adjustments before the glue hardens completely. Only a small amount should be used to avoid damaging the items to be glued. Medium viscosity is the type that usually comes in plastic bottles with a thin applicator to apply the glue. It dries faster than the thick tube cement, but still allows plenty of time to make adjustments. Ultra-thin comes in a bottle with a brush applicator in the cap. You can also use a small, detail brush for application. The disadvantage is that it is harder to control, as it dries very quick and does not allow for much time to move the glued pieces into place. An advantage to the ultra-thin variety would be that it dries fast which means it is less likely to damage the surface of the plastic. When using model cement to glue dissimilar plastics together, it is best to use Plastruct Plastic Weld. However, if gluing two similar plastics together, use Plastruct Bondene (ex: ABS to ABS or styrene to styrene)
Epoxy is excellent for joining parts that don’t fit tightly together. This type of glue consists of mixing two compounds together--a hardener and an adhesive, or resin. You need to mix equal parts and then apply to both surfaces. Some epoxies come in a double syringe like Devcon Plastic Welder. Others, like Z-poxy come in two separate bottles. The benefits to using an epoxy is that it tends to be able to glue almost any material. Be sure to read the labels, though--for example, Z-Poxy works great on all plastics except polystyrene, and Devcon Epoxy (not to be confused with Devcon Plastic Weld) does not work on polyethylene or polypropylene. Devcon Plastic Weld works well on most hard-to-glue plastics such as polypropylene and polyethylene. A disadvantage would be that you may tend to mix more than you’ll use each time, and therefore waste the glue, as once it is mixed, it must be used immediately.
Z-Poxy 5 Minute Formula is a type of epoxy glue that consists of a resin and hardener.
E-6000 is a great multi-purpose glue that works well on many surfaces, however it does not bond well with most plastics. It is recommended for acrylic, PVC, and vinyl and is not recommended for use on styrofoam, polystyrene, polyethylene, or polypropylene. The fumes from E6000 are also very strong and should not be inhaled. Be sure to work in a well-ventilated area and avoid contact with skin. The advantages to E6000 are that it is flexible, photo safe, as well as washer and dryer safe. Duco Cement works great, but it does lift the color off of the plastic, so just be aware when gluing two items of dissimilar color together. Duco Cement works well on ABS, PVC and polystyrene but is not for use on polyethylene, polypropylene or styrofoam. Both come in a tube for easy application.
E-6000 is a common “multi-purpose” glue but does not work with all plastics
How to Glue Plastic
Before you begin, it is always best to make sure that you are working outdoors or in a well-ventilated area. Exposure to plastic glues can cause headaches, nausea, light-headedness, dizziness, and skin and eye irritation. Some glues require the use of gloves to protect your skin. Be sure to follow all directions and precautions listed on the packaging.
It’s also a good idea to test a small amount of glue on your surface to see how the glue might affect the surface and also to see which glue is best for the project. For my test, I’m using Legos (made of ABS plastic) and several glues: Z-Poxy 5 minute formula, Devcon Home Plastic Welder, Duco Cement, Testors Plastic Cement, and E-6000. I’ve shown the process for using epoxy glue below. Besides mixing the epoxy glue together, all of the other steps shown can be used when using other glues. Follow the directions on the package for best results.
No matter which glue you use on plastic, for the best results, it’s always good to start with surfaces that are clean, dry and free of debris. If possible, rough up the areas you’d like to glue together with some sandpaper to create “tooth” or something for the glue to hold onto. Plastics can be hard to glue to each other because they are smooth and nonporous which makes them fairly non-stick surfaces. Lightly sanding the surfaces will make the bond more secure. Also be sure you are using the right glue for the job, as certain plastics do not work well with certain glues, and some glues are especially for gluing certain plastics only, or gluing the same plastics together.
Use sandpaper to rough up the surface to which you’ll apply the glue.
Make sure to sand both surfaces.
When using an epoxy glue like Z-poxy 5 minute formula, you’ll need to mix equal parts resin and hardener in a separate container. Here I’ve just used an empty yogurt container and a wooden brush handle. You could also use a popsicle stick or similar tool for mixing as well as for application. Use a toothpick to apply glue to a very small item. Since I’m only gluing small items, I am only using a little bit of glue. Only mix the amount you’ll need to use each time; once it is mixed, you will not be able to save for future use.
When using epoxy glue, mix two equal parts resin and hardener.
Mix the resin and hardener together using a wooden handle or popsicle stick.
Apply a small amount of glue to each surface:
Apply a small amount of glue to each surface
And press and hold or clamp together until set (set times vary per glue):
The two items will be set in about 5 minutes and handled within 30 minutes. Allow at least 16 hours for full cure time.
Each glue has a different set time, handling time and cure time. Some are quicker to set than others, and most have a handling time that range from minutes to an hour. Most will fully cure within 16-24 hours.
When you’re using an epoxy glue like Devcon Home Plastic Welder, you’ll also need to mix equal parts resin and hardener. This glue comes in a syringe-like applicator and all you need to do is open the cap at the bottom and push the plunger to squeeze out the amount of glue you’ll need for your project. It’s a good idea to test out how much of each glue is coming out when you first open it to ensure you are getting an equal amount of each. Once you’ve tested it to make sure equal amounts are coming out, press out more into a separate container (or different side of the same container, if using a small amount as shown below), mix thoroughly and apply.
Testing out a small amount to ensure equal amounts are flowing out of the applicators at the same time.
The Devcon Home Plastic Welder has a very strong odor, so avoid breathing in the fumes--it’s best to use this glue outdoors. It is also recommended that you wear gloves when using this glue to avoid skin contact. If contact occurs, wash immediately and thoroughly with soap and water. If you are sensitive to strong odors, I recommend Z-poxy to Devcon, though both do a great job at bonding the same type of plastics together.
Glue Test Results
I tested the strength and compatibility of a few different types of glue on Legos (made of ABS plastic). I found that Z-poxy, Devcon, and Duco Cement worked best. They were inseparable and had formed a very strong bond. The Duco Cement lifted some of the color off the plastic while gluing together, however, so just be careful when using around painted-on details if working with plastic model kits, and have a paper towel or rag handy to wipe away excess glue. The E-6000 and Testors Cement for Plastic Models did not adhere the two pieces together at all, but that is due to the fact that the Testors Cement is really for polystyrene plastic only and E-6000 does not work on all plastic types. (It should be noted also that all were checked after 24 hours and E-6000 may require items to be fully cured for up to 48-72 hours in some cases) For bonding ABS plastic to itself, Plastruct Bondene is recommended. Overall, it’s always best to test your plastic glue on scrap pieces first, to test the strength and compatibility. It’s also best to have a variety of glue handy to meet all of your plastic glue needs from model construction and general crafts to home repair projects.
Tools & Materials
Plasti Zap 1/3 oz$4.59
Hot Stuff Super T 1 oz. (Yellow)$6.99
Hot Stuff 2 oz. (Red)$11.50
Hot Stuff Special T (Green)$12.50
Testors Plastic Model Cement 5/8 fl.oz.$2.79
Plastruct Plastic Weld 2 oz.$6.99
Micro Weld 1 oz. Bottle$4.50
Devcon Plastic Welder 25 ml. Syringe$7.69
Pacer Z-Poxy Quick-Set 4 oz.$11.99
E6000 (0.5 oz.)$3.99
Duco Cement 1 oz. Tube$3.99