A plastic material is any that can be molded or shaped, but the term is specifically used nowadays to refer to a class of synthetic organic polymers with nearly magical properties. The heathen scientists insist that these materials are formed from chains of simpler hydrocarbons. They are named for the hydrocarbon monomers used in this chain; hence a molecule of polyethylene, used in plastic bottles, is made up of many molecules of ethylene.
Plastics contain resins, plasticizers, and fillers. The resin is the plastic itself. Plasticizers are stabilized oils that increase the flexibility of a plastic that they have been added to. (The vinyl in the seats of your 1972 Dodge pickup is the same plastic as the hard vinyl siding on your house; it has just been plasticized). Fillers are substances added to the plastic, sometimes to reduce the cost, and often to impart desirable mechanical properties, such as dispersing microscopic plastic bubbles throughout the material to improve its resilience.
Common plastic resins used in Transformers toys include:
- Polycarbonate (PC)
- Can be transparent or opaque. This is the same plastic that CDs are made from. Any clear parts on a Transformer, such as windows and light-piped eyes, are PC.
- Acrylonitrile butadiene styrene (ABS)
- Strong and tough "engineering plastic". Lego bricks and car bumpers are made from ABS. This is what the majority of any given Transformer toy is likely to be made of. ABS also seems to suffer from a condition called Gold Plastic Syndrome when colored the goldish-bronze color seen on some figures. However, not all gold plasic suffers from this, and mostly older plasics (pre-RID) seem to exhibit this problem. It is currently unknown if the gold-colored parts of the Movie toys will show this form of rot.
- Polyvinyl chloride (PVC)
- Strong and hard,PVC can be made rubbery with the addition of plasticizers. Flexible PVC is often simply called vinyl. Most "rubber" tires are actually PVC.
- A very tough, resilient, slippery plastic for mechanical parts. Any gears or small gimmick-related pieces are likely POM. POM cannot be painted.
- One brand name is Nylon; similar properties to POM, but stronger. Often used for larger parts that require resiliency such as ball joints. PA cannot be painted.
Other plastics that are commonly used in toys are Polystyrene (PS), Polyethylene (PE), and Polypropylene (PP), however none of these are currently used for Transformers toys.
Most plastics in Transformers and other toys are thermoplastics, which liquefy when heated. Thermosetting plastics, an older technology, solidify when heated, and are still widely used for many purposes, but only very rarely in toys (occasionally they are found in motors).
Thermoplastics are science's gift to the toy industry. They can be melted at fairly low temperatures, molded in colors with fine detail, and stand up well to play wear because of their resilience. They can be made transparent or opaque. They are electrical insulators. Finally, there are a great many plastics, as we have begun to see in the above list, with a wide variety of material properties, which makes it very likely that a suitable plastic could be found for a particular job.