Professor Honeycutt: Why actually, yes I am, and a plastic fiber compound.
In Real Life, plastics are used for parts in robots and other machinery. In Science Fiction, you can have indestructible robots made entirely out of plastic. Plastic composite-alloys that are lighter and stronger than steel. With added benefit of not rusting like metal, plastic can last for hundreds of years, maybe even forever in a world run on Raygun Gothic, Cassette Futurism or iPunk. They're easier to mold into the perfect shape and might even be cuttable with scissors, yet make the perfect material to build rockets that can withstand the overwhelming heat of reentry and the intense pressures of the ocean.
To those unfamiliar with the chemical and historical significance of common polymers, plastic is a varied type of synthetic and semisynthetic material that by the 21st-century has become as common as the likes of glass and metal. It is a light-weight, long-lasting material used in countless applications from packaging, construction and electronics, to energy production, sports, healthcare, color-dying, art, mass production of goods and services and the list goes on and on.
Much like radiation, plastic is a miracle of science that was not available for wide-spread use in the cultural zeitgeist until the 20th century (specifically 1907), and like radiation, fiction likes to think it is capable of anything. Sometimes these advanced "plastics", if the fiction goes that far, are said to be reinforced with ceramic or crystalline matrices, carbon or metallic nanotubes, etc. Sometimes they're plastics in name only, making it a case of Translation Convention.
And, much like radiation, plastic is not without its pitfalls. The environmental and health impact of plastic has only just begun to be addressed, most plastic doesn't biodegrade, instead breaking down to individual molecules which then find their way into animals, all the way back up the food chain into us. Even supposedly biodegradable plastics require industrial composting conditions to break down.
One of the Ur Examples of this trope is the commonly used "plasteel", a term coined by Harlan Ellison as a fictional compound made up of polymer and steel, said to combine the elasticity of plastic, the heat resistance of metal, and the strength and durability of both.
- In most versions of the titular Robot Kid Astro from Astro Boy, his skin is made of an artificially created super-plastic that makes him virtually indestructible against anything, from the crushing ocean depths to direct exposure to the surface of the sun.
- In Dominion Tank Police, "The Ultimate Deterrent" are large packs of two octagonal plates of primary-coloured plastic stuck together in an 8-shape, which don't register as lethal weaponry when scanned, but if driven over, turn into hilariously-huge penises that flip over whatever was driving across them. They're very effective.
- The version of Doctor Octopus present in Spider-Man: Into the Spider-Verse possesses soft robotic tentacles made from a "semi-transparent silicon material that expands and contracts like membranes" (according to Word of God) that's strong enough to lift herself and various heavy objects and rip through full-grown trees.
- The main villain of Yogi the Easter Bear is a Corrupt Corporate Executive named Paulie, who owns a plastics factory and is completely obsessed with plastic. One scene has him go into a rant about how plastic can be used to make virtually anything, during which he reveals that his clothes, false teeth and toupee are all made of plastic.
- Star Wars:
- Plasteel is plastic-like material used heavily in construction, armor and a wide variety of other practical uses, most famously as the material in Darth Vader's helmet.
- Plastoid is a type of light-weight material that superficially resembles plastic that, while vulnerable to blaster-fire, is resilient to a host of other things, including chemical warfare. It is used for a a wide variety of things, most famously as armor for Empire Stormtroopers.
- Plasteel in Dune was any kind of composite of organic polymer and carbon-iron alloys used in many industries due to both its plasticity and Macroscopic hardness.
- In Agents of S.H.I.E.L.D., Chronicoms are an intelligent alien race that, while human-looking on the surface, are actually a race of Mechanical Lifeforms. Whenever Enoch is referred to as a robot by his human friends, he insists that he isn't a robot and that he is made from a plastic alloy.
- In Doctor Who, the Autons are robots made out of living plastic (such as shop window dummies), animated by the Nestene Consciousness.
- In Starfinder nearly anything (aside from necrografts) can be crafted from little grains of plastic called Universal Polymer Bases (UPBs). The Pact Worlds credit is even pegged to the UPB, with an item's purchase price being equal to the number of UPBs need to craft it.
- Plasteel from Warhammer 40,000 is a type of advanced synthetic material that has the consistency of plastic but the tensile strength of a steel alloy that was developed during the Dark Age of Technology, but long used by the Imperium of Mankind in the construction of many types of personal infantry armor. Heavy-duty plasteel were combined with the heat-resistant ceramic material called ceramite to craft the plating of Terminator Armour when the Adeptus Mechanicus still maintained the technical knowledge required to manufacture it.
- Wraithbone, used by the Eldar for pretty much everything from weapons, to starships is a magical variant created from more or less solidified warp energy. It is manipulated via singing
- GURPS has rules for plastic golems, especially popular in GURPS Technomancer. Magic Items 4 includes Bakelite golems, for less advanced Magitek worlds.
- In Fallout 4, plastic is one of the crafting materials the player can salvage. It's mostly used to build and upgrade energy weapons and other advanced technology.
- In RimWorld, plasteel can be used for a lot of high tech devices needed for the spaceship to escape from the planet. It's also extremely effective if worked into bladed weapons or body armour. There's also an extremely rare and implicitly-synthetic fabric known as "hyperweave", which is moderately blade-resistant but mostly notable for being an incredibly good insulator.
- In Subnautica, plasteel is a material used in advanced fabrication, particularly of pressure-resistant submersibles and upgrades to same. For some reason it's crafted from a combination of titanium and lithium.
- In X-COM: Terror from the Deep, the alien alloys and related technology from the 1st game will corrode quickly in seawater. This forced X-Com to research the aliens' Aqua Plastic to create a material that's similarly as strong as the old alien alloy but won't break down in saltwater.
- Parodied in the Donald Duck cartoon "The Plastics Inventor", released in 1944, just as plastics were becoming mainstream. Following the instructions from a radio show, Donald makes a plastic airplane by melting down random junk and pouring it into a mold, then baking it. The finished plane flies like a dream, but there's one drawback: it's not waterproof. As soon as Donald flies into a downpour, the fuselage starts melting away.
- In the Futurama episode "Forty Percent Leadbelly", Bender's hard-drive becomes wirelessly connected to the Bluetooth of a giant 3-D printer to create whatever in his hard-drive out of nanoplastic. While he originally only wanted to replicate Silicone Red's guitar (the nanoplastic-guitar sounding indistinguishable from a real one), the printer begins to automatically print whatever he is thinking as perfect replicas, including three robots (one of which is a perfect replica of Bender), Fry, a fully functioning train and a giant octopus.
- In the Super Friends episode "The Fantastic FRERPs," a villain known as King Plasto uses a new form of plastic, called FRERP (Fiber Reinforced Epoxy Resin Plastic), in his attempt to establish his own kingdom, Frerpland. Objects made from FRERP are compressed inside egg-shaped containers and come in two forms, solid and inflatable.
- In the Teenage Mutant Ninja Turtles (2012) episode "The Evil of Dregg", when Casey calls Professor Honeycutt "metal" after he rescues them from Dregg, the professor misunderstands the compliment and clarifies that he is indeed made of metal, as well as a plastic fiber compound.
- X-Men: The Animated Series: In "The Final Decision", Magneto is confronted by a Sentinel, which is a gigantic android designed to hunt down mutants. The villain smugly proclaims that no robots can resist the master of magnetism, but the machine counters by explaining that it's made entirely of plastic.
- X-Men: Evolution: In "The Cauldron - Part 2", the mutants who were not abducted in Part 1 board the X-Jet and travel to Magneto's hideout. When Toad points out that it doesn't make sense to confront the master of magnetism while aboard a plane, Wolverine retorts that there is not an ounce of metal in the vehicle.
Toad: You mean we are flying in cheap plastic?
- In 2007, engineer professor Nicholas Kotov created a multi-layer polymer called "plastic steel," a water-proof material that could potentially be used in the construction of armor for soldiers and police, vehicle construction, unmanned aircrafts, microfluids and various other applications.
- 3D printer technology is often hyped up this way, as in theory the tech enables anyone to create any object (including guns) out of plastic at home from just a digital blueprint and some plastic pellets. While development continues to advance by leaps and bounds, the plastics and printing mechanisms used in early generations of the technology have traditionally struggled with issues of stringiness, brittleness, gaps in thin surfaces, and incomplete fusion between layers. Advanced models are increasingly reliable and precise, but designs still need to be engineered to minimize the potential effects of print errors and weaknesses,note and assume some degree of manual clean up will be required even on the cleanest outputs.
The applications of 3d printing receiving the most interest from scientists and engineers loop back to this trope by allowing the fabrication of unusual amalgam materials that aren't possible with traditional methods. For instance, a flexible polymer can be impregnated with fibers of another polymer to create muscle-like "soft actuators" that contract in response to current or other stimulii, or precisely imbued with metals and glasses to create integrated circuits printed as a continuous object.
- There is work to develop plastic that is magnetic, first synthesized by Pakistani scientist Naveed A. Zaidi. It's generally non-reactive nature could be useful to replace the metallic implants like pacemakers to increase the chances of their compatibility.