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| 16 Part Epoxy |
 Title text: Some surfaces may seem difficult to glue. But if you research the materials, find tables of what adhesives work on them, and prepare your surfaces carefully, you can fail to glue them in a fun NEW way that fills your house with dangerous vapors. |
Explanation
This comic refers to Epoxy โ substances used as adhesives, sealants, and coatings, named for a particular chemical substructure that's key to these substances turning from liquids to solids. Many types of epoxy are multi-part, usually two, where the components, such as resin and a hardener, are stored separately. For ease of use, this can be in parallel syringes (of equal volume, or proportionately different widths to maintain the correct mixing ratio) such that the user simultaneously squeezes out the separate chemicals by depressing both syringes at once, onto the initial surface or into a container. The user then thoroughly mixes the components, as quickly as possible. The mixture is spread evenly (or as necessary) over the surface(s) to be joined or protected, and if there are multiple parts they are quickly positioned. The combined epoxy quickly cures, usually within a few minutes. This comic presents a fictitious 16-part epoxy, with the same apparent logic of parallel deposition in mind, with many components that are implausible or make fun of common problems people have when using epoxy in real life.
The title text references how not all epoxies and glues work on every material, and that applying them on some can require special techniques or products. Some industrial or industrial-grade adhesives contain solvents (e.g. tetrachloroethylene, which is used in E6000 glue) that release harmful vapors as they cure. If used improperly, this can result in the release of chemical vapors in an enclosed space along other dangerous side-effects, while also not working as a glue as intended.
| Type | Real? | Explanation |
|---|---|---|
| Resin | Yes | A liquid which turns into a polymer when mixed with a hardener. |
| Hardener | Yes | A thick liquid which is mixed with resin to create a durable polymer which is commonly used as a glue. |
| Filler | Yes | An optional addition to the hardener and resin which changes the properties of the polymer.
Some epoxies are sold as products known as 'fillers', used to repair and cover cracks, holes, and imperfections. |
| Softener | Yes | A substance which is added to polymer to soften the polymer and increase its impact resistance. |
| Rosin | Yes | While this looks like a joke entry, this is actually an alternative to resin which is extracted naturally rather than synthesized from other chemicals. Rosin (also commonly known as 'flux') is one of two parts that make up rosin-core solder, used in electronic circuits, where the rosin is located in the center (the "core") of the solder and helps the solder to melt and bind better, as well as letting it 'wet' the surfaces to be soldered better — in this case the two parts are touching rather than kept completely separate, as rosin and the solid solder require heat to mix and do their combined jobs, unlike common combination epoxy chemicals that will be both liquids that cure together on contact even at room temperature. Rosin is also frequently applied to the bows of string instruments like violins or cellos to improve the sound, as immortalized in the famous song "The Devil Went Down to Georgia". |
| Stuff that bonds permanently to skin and nothing else | No | One key annoyance with sticky substances is the difficulty of removing them when they bond to skin. In this case, the polymer bonds solely to skin instead of anything else, making it mostly only really useful for a practical joke. Some epoxies are specifically designed for gluing skin, usually for medical purposes, but none are known to bond to skin exclusively.[actual citation needed] This may be a reference to cyanoacrylate adhesives ("super glues"), which famously bond quite aggressively to skin while often failing to bond the target materials. |
| Stuff that will crack and turn white over a few days, for decorative appearance | Not effective as epoxy | 'Crackle effect' is a real thing for crafters, and can be created by mixing paint and glue, but is not recommended if you want two surfaces to adhere, since most paint is made to be non-adherent in order to be durable[actual citation needed]. Poor finish, where an intended smooth uniform surface cracks or discolors, can be a frustrating problem when applying epoxy mixtures to visible surfaces, especially when the problem only appears some time after you've congratulated yourself on a job well done. |
| Placebo | Not in the field of adhesives | The placebo effect happens when somebody is told that something has a certain effect, when in reality there is no effect. This is commonly used in medical studies to determine whether a medication actually does something as opposed to simply having a psychosomatic effect. Using this term to describe a type of polymer suggests it would make someone believe it is gluing things together without actually doing anything, which is unlikely. Alternatively, this could refer to a component or filler that claims to serve a specific purpose while having no true benefit, causing the perception of benefit to the consumer (presumably causing better reviews). |
| Minced duct tape | Not intentionally | Duct tape is widely used as a way to join and/cover things, sometimes in contexts where an epoxy might provide a more high-quality solution. Randall is pretending that having very small pieces of tape in the mix would add to the epoxy's ability to hold things together. In reality, cutting duct tape into small pieces would weaken it and make it less effective at sticking things together. In the UK, the word 'minced' can also mean 'made worthless', which would also not fare well for the adhesive. |
| Acetone fragrance | No | Acetone is a volatile solvent used in a number of glues and paints (incl. nail polish), but it weakens epoxy and can even be used to remove uncured epoxy. It has a strong, distinctive, very unpleasant smell, and is actually toxic, meaning that fragrance is an odd reason for adding it to any product. It would give the epoxy a familiar "chemical smell" that people associate with industrial compounds. |
| Powdered bar magnets | Yes, but not in resin | This might still work if the pieces could somehow be aligned correctly, as each tiny piece of magnet would still be a magnet in its own right, capable of attracting the other tiny magnets, and thus resisting tension forces. However, it would be much worse than a normal bar magnet, since the magnetic force would be weaker than those that held the original bar together. The micro-magnets would tend to clump together, which might strengthen the glue, but wouldn't help it to bond to surfaces very much unless the surfaces themselves were strongly magnetic. |
| Polyethylvinylesteracetate | Not in epoxy | This appears to be a reference to Poly (ethylene-vinyl acetate), some formulations of which can be used as the adhesive in hot-glue guns. Vinyl acetate is an ester, so the inclusion of that term is redundant. The cadence of the constructed word may also be a reference to the television episode Lucy Does a TV Commercial and its memorable product "Vitameatavegamin". It also resembles the kind of thing often seen in ingredients lists for common household products such as soaps and cleaners, which are fairly meaningless to the average person buying them. |
| 2-Polyethylvinylesteracetate | Unclear | This sounds almost exactly the same as the above item, but a name with a "2-" prefix generally indicates that the initial bit of the name is a functional group attached to the second position along a chemical chain (often being the carbon-carbon 'spine' of a molecule, in large-molecule organic chemistry), rather than attached to its end. Because the molecule name is (possibly deliberately) malformed, it's hard to tell what is supposed to be attached to the second carbon of what subunit. |
| Salt and pepper to taste | Not for taste, but salt can be useful | Salt and pepper are two incredibly popular condiments which are used to enhance a dish's flavor, and "salt and pepper to taste" is a phrase found in many food recipes. But the taste of your epoxy should not be your concern. Do not eat epoxy. However, salt or sand or other fine grains are sometimes recommended to add a bit of grit to an adhesive. Generally glues or epoxies need the bonded materials to be firmly held together while the glue cures. But when first pressed together, any excess glue is squeezed out and can cause the surfaces to slip around and need to be re-aligned. Any extra friction in the epoxy can help alleviate that. |
| Blood sample from the Gorilla Glue gorillas | No[citation needed] | Gorilla Glue is a popular brand of superglue which uses gorillas as its mascot. In this case, the blood of the gorillas would be extracted and placed in the polymer, which would dilute and possibly weaken it. Insofar as Gorilla Glue gorillas exist, they are depicted as ordinary gorillas who just happen to carry glue everywhere. Extracting and consuming the blood of a creature or person in an attempt to inherit some of the qualities of the 'donor' is a kind of sympathetic magic, so this may be suggesting that including this will give the epoxy 'the strength of a gorilla', commonly considered a powerful animal.
Blood has been historically used in glue, though not typically that of gorillas. |
| Stuff that bonds to every known material except yours | Probably not | Another common annoyance when using an adhesive is that each glue type only forms an adhesive bond with certain materials. In this case, the polymer would bond with every material except for the one you were using, causing great distress and leaving you in a fix. This is similar to "Stuff that bonds permanently to skin and nothing else" above. |
Transcript
Standard 16-Part Epoxy
[An epoxy applicator with a single push bar and sixteen differently-colored chambers, each labeled]
Resin
Hardener
Filler
Softener
Rosin
Stuff that bonds permanently to skin and nothing else
Stuff that will turn white and crack over a few days, for decorative appearance
Placebo
Minced duct tape
Acetone Fragrance
Powdered bar magnets
Polyethylvinylesteracetate
2-Polyethylvinylesteracetate
Salt and pepper to taste
Blood sample from the Gorilla Glue gorillas
Stuff that bonds to every known material except yours
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