Q&A for How to Make Bioplastic

The more glycerin you use, the more the plastic will be rubbery. So if you put less, the plastic will be harder but more brittle.

Glycerin is used as a plasticizer that links polymer chains together and allows them to slide past each other. Vinegar helps the corn starch to fully dissolve in the mixture because starch dissolves better in the presence of electrically charged ions. If you do not have vinegar handy, ordinary table salt can also be used to help the corn starch to dissolve because it can provide free ions.

Ordinary table salt can be used as substitute for the vinegar.

Depending on which country you reside in, corn flour and corn starch may be the same thing. Outside of the United States, many countries call corn starch corn flour. Within the United States, corn flour is similar enough to corn starch that it should work to make a homemade bioplastic.

The glycerine acts as a "plasticizer" to link polymer chains and allow them to bend. Sorbitol can also be used as a plasticizer in place of the glycerine. Glucose and sucrose can also be used as a plasticizer, although they are less common and you might need to do some experimenting on your own to get the amounts needed correct.

Soil, microorganisms, humidity, sunlight, and oxygen are the conditions needed for bioplastic to decompose.

Yes, it is biodegradable as it is made from biological substances.

The time it takes will vary based on the conditions for decomposition and the size of the plastic. Some bioplastics require high heat to decompose and cannot actually be composted in a back yard compost pile. It can take a few months to years for bioplastics to degrade.

The plastic should be molded immediately after heating. If you are molding it with your hands, you will want to let it cool enough that you can comfortably handle it. If you are pouring into a mold, simply pour it directly into the mold after removing it from the heat.

Yes, it can be used in many applications that petroleum-based plastics are used for.

You won't be able to mold it if it is hard and dry. You'll have to start again.

Look on eBay for denture soft liner. It's inexpensive and will be better for ill-fitting dentures. Also it will last longer in the presence of alcohol and food.

There are many available brands of glycerin, you just want to make sure that you purchase the pure 100% glycerin. Some drugs stores like CVS and Rite Aid carry the products in the skin care aisle. You could probably find it at Walmart or GNC, too.

It is biodegradable, which makes it better for the environment than regular plastic.

You can re-melt the plastic, but it may be more brittle when it dries the second time.

Yes, the oil will make it easier to take the plastic out from the mold.

Of course you can! Just make sure you have proper air conditioning to avoid the fumes.

Glycerin from corn. It helps with the polymers and allows them to be stronger.

Potato starch works well, creating a rather translucent form. Tapioca starch works as well, creating a much more rigid and durable form.

No, you need these ingredients.

Any starch would work. All starches are biopolymer, which is what makes cornstarch viable for bioplastic.

No. Parchment paper normally can get up to 450 to 500*F, so it should work for this project.

For method one, 1.5 grams of glycerin is 1/4th teaspoon; this would be equivalent to 1.25 ml of glycerin.

The amount of plastic produced will vary between the two recipes. You can make more or less bioplastic by doubling or halving each recipe.

It's not waterproof, but can be exposed to water temporarily. The one with gelatin will become more jello-like, but then will reharden.

You don't need plastic to make bioplastic. You can either follow the video or look up other recipes.

Adding less glycerin will make the bioplastic tougher, but will also make it brittle. You may want to let the plastic sit for a few extra days to let it harden more.

You could pour it into a bowl and turn so that it coats everywhere, then put another bowl over it to maintain the shape.

No. It's not good for your health. When you heat milk, it becomes alkaline because it is decomposed.

It will naturally break down over time without humans interacting with it.