How Are They Made?
As the name implies, they are made from corn starch. The starch is converted into a polymer, the main ingredient in materials that have a plastic-like feel. The plastics can be clear or opaque, soft or hard. A kind of acid called polylactic acid (PLA) is made from the corn starch. This is why they are sometimes called PLA plastics.
PLA plastics are molded the same way conventional plastic is. They can be molded, extruded, or shaped by heating and cooling (thermal shaping).
More than Biodegradable
Biocompostable plastics are called so because they are a step beyond just biodegradable. For a plastic to be considered biocompostable, it must meet certain criteria. For instance, it must decompose at the same rate as paper, and it must break down into harmless material such as water, carbon dioxide, or biomass (organic matter).
Biocompostable plastic must not produce any toxic substances as it decomposes. It must also break down to the point that it cannot be discerned or filtered out of the surrounding compost. PLA plastics cannot be recycled. They must be composted.
Advantages of Biocompostables
* No toxic chemicals associated with conventional plastic (such as polyvinyl chloride or dioxin)
* Can be disposed of in your home compost pile
* Eco-friendly (made from a renewable resource and less wasteful)
* Especially well-suited for cold applications, such as in the freezer (this is good news, since chemicals from conventional plastic tend to leach into food when frozen)
* Corn allergies are not an issue since the allergen, profilin, is destroyed in the manufacturing process.
* May not be as heat resistant
* Not microwave safe
* Can’t be thrown in the garbage or recycled; must be composted at home or in a commercial facility
* Thicker, harder items such as cutlery can takes up to 180 days to break down
Types of Biocompostable Items
There are all sorts of items that can be made with PLA plastic. Here are some of them:
* Cups (hot and cold)
* Water bottles
* Food storage containers (including “clamshell” containers used by take-out restaurants)
We hope that Corn Starch Biocompostables – What Are They? helps you to better understand biocompostables, which is a promising new technology!