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16 Part Epoxy
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.
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, a substance used for attaching other materials. Many types of epoxy are multi-part, 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 suitably different where a mixing ratio of 2:1 or 3:2 might be desired) such that the user simultaneously squeezes out the isolated chemicals by depressing both syringes at once. They are then mixed together on the target surface, so that the combined epoxy quickly cures into the desired solid, binding whatever surfaces upon which it is applied and then brought into contact with. 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.
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 is frequently applied to the bows of string instruments like violins or fiddles 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 it when it bonds to skin. In this case, the polymer bonds solely to skin instead of anything else, making it more 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] The most common kinds are moisture-activated, which means they will not easily bond to fully dried surfaces, where often most non-skin surfaces are dry.
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].
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, but Randall is using this term to describe the type of polymer. This makes no sense, because the polymer would need to make someone believe it is gluing things together without actually doing anything, which is highly 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 No Randall is pretending that having very small pieces of sticky duct tape would make a good adhesive. In fact, 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 augur 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 fragance is an odd reason for adding it to any product.
Powdered bar magnets No While this would still work, as each tiny piece of magnet would still be a magnet in its own right, it would be much worse than a normal bar magnet due to the random orientation of each piece.
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".
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 (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 in the field of adhesives Salt and pepper are two incredibly popular condiments which are used to enhance a dish's flavor. Using this would have no effect on the polymer.
Blood sample from the Gorilla Glue gorillas No 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 have no effect because they're depicted as just regular gorillas that happen to carry glue everywhere.
Stuff that bonds to every known material except yours No 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.

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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