Plastics have become a major part of everyday life over the last 50 years. This is certainly true of plastic cutlery, which allows people to have parties or go on picnics without having to carry metal knives, forks and spoons. Plastics have also become a major part of the take-away restaurant trade and is now a multi-million dollar global industry. The basic manufacture of plastic cutlery is the same regardless of the plastic, but the actual plastic used does vary from company to company.
Polystyrene is most commonly associated with protective packaging, but it is also the most common plastic for spoons. At room temperature, this petroleum-based plastic is similar to glass. Although it appears solid, it is in an incredibly viscous state.
As plastic manufacture requires petroleum, which is becoming more expensive, many companies now manufacture oxy-biodegradable plastic spoons. These are designed to biodegrade naturally after being discarded, and thus less harmful to the environment. These plastics include polybutaline and polycaprolactone, although they can also be made from starch derivatives.
This petroleum-based plastic is much less common than polystyrene in plastic spoons, but still makes up a significant part of the market. It is quickly being overtaken by biodegradable plastics, both through consumer demand for environmentally friendly products and because it is more valuable elsewhere. Because polypropylene is resistant to most chemical solvents and acids. it is used a lot in the automotive and aerospace industries as well as in the manufacture of laboratory equipment.
Technically, any plastic that is solid at room temperature can be used to make plastic spoons, but many plastics are used in surprisingly specialized areas, and the three mentioned here are the ones most commonly found in cutlery. It is very likely that in the next decade both polystyrene and polypropylene will disappear from this market as demand for biodegradables increases, and as manufacturers realize there is more profit elsewhere.