Easy Biodegradable Plastic

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About: I make K'nex guns, specializing in semi-automatic, RBG-Slingshot hybrid systems which i use in most of my guns. Note: I am not responsible in any way for any damage, injury, or death caused by my Instructab...

Now lots of products are made out of plastic. A lot of it is throw away and will stay in garbage dumps of thousands of years. Biodegradable plastic, unlike normal plastic made from petroleum, will decompose and become part of the soil. This Instructable will show you how one easy way to make some biodegradable plastic.

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Step 1: Gather the Materials

This are lists of materials and tools needed to make the biodegradable plastic:

Materials:
-Corn Starch
-Water
-Cooking Oil

Tools:
-Spoon/Something To Measure With
-Microwavable Container
-Microwave

Step 2: Proportions

The proportions to make the plastic are:

1 TBSP Corn Starch: 1.5 TBSP Water: 3-5 Drops Cooking Oil

Step 3: Preparations

Mix the ingredients together to form a milky looking liquid. Once you have done this it is ready to be microwaved.

Step 4: Microwaving

Put the mixture in the microwave and set the microwave on high for 25-30 seconds. The mixture should start to bubble and should become slightly transparent. Keep an eye on the mixture to make sure nothing goes wrong.

Step 5: Molding the Plastic

When it looks slightly transparent, take it out. Let it cool a bit so you can handle it. Then knead the plastic until it is soft and can be molded like play-dough. Now you can mold it into whatever shape you want it to be. Once molded leave it for about 24 Hrs. for it to cure and become solid. It's best to keep the surface from drying out while it is curing. The image below is the plastic when shaped.

Step 6: Ideas

-You can add food coloring to give the biodegradable plastic some color.

-You can use it to make plant pots so you start the plants indoors and when they've grow you can put them in the ground.

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68 Discussions

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Frankenbride

3 months ago

I made this and was looking for transparency. I got quite a bit of shrinking, which I think I could remedy with the OP's suggestion of damp paper towel. But mine never became transparent. This is an "I made it!" photo. How can I get it to be this transparent? Muhassan, are you still here?

gel.jpg
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bigoof

4 months ago

recommend putting in a plastic piping bag with a round tip if you have trouble using it.

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Gruonabike48

Question 4 months ago

When you make it can it be molded to be like plastic bottle or can six pack rings? Would it be flexible enough to work as one?

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PaulinaD9

4 months ago

Has anyone tried putting it in wet soil and see how long it takes to decompose? If not, I'll try to make it this weekend and see what happens.

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saeed hawit

Question 5 months ago on Step 5

What does it mean by its better not having the surface dry out

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kodgirkarsakshi

Question 1 year ago on Step 6

For making the pots we should have bigger container so how​ can we microwave it

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wbraun1

2 years ago

Sounds great. My mold is Schedule 40 PVC and I am afraid the microwaving will damage the mold.

Suggestions please.

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dennise.espantowbraun1

Reply 1 year ago

microwave the mixture then put the outcome in the mold and wait for it to cure

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ChristopherP224ShramanD1

Reply 2 years ago

Water and heat make the starch polymers unfold and line up like normal plastic polymers (it's called gelatinization). Once this takes place, starch can be modeled in to what ever shape you want. Unfortunately, without adding other fillers, this plastic will break very easily and will melt in water. Not sure what the oil is for...

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patpat23ChristopherP224

Reply 1 year ago

Hello, it looks like you are very smart. Do you know the specific reason for why are the proportions this way?

Thanksssssssss

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wbraun1

2 years ago

I want to use this in a form made up a form made from schedule 40 PVC double walled tube, to make a biodegradable round tube with a closed end approximately 6" long and 2" OD. Can I use a regular oven in place of a microwave and at a temp of approximately 130 degrees (so not to melt the PVC).

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msminnamouse

2 years ago

Thanks! This is perfect for what I need!!!

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pete.hohensee

2 years ago

It was hard to work with. Kept sticking to my fingers.