how do you make plastic?

Answer 1

Plastic is a petroleum product that is made in factories. They heat the hydrocarbons that come from oil, natural gas, or coal using a process that requires over 850 degrees centigrade. They then add various chemicals to make up the different types of plastics that become the products we use.

Once a plastic "sets" in the mold, it cannot be "unset" because of the polymers. It is like a cooked egg, it can not be melted back down. Sometimes the edges of the plastic product can be melted, but when they cool, they revert back.

For more on making plastic, see the excellent article from Plastics resource at the link I have provided for you.

You can buy liquid plastic and resin to pour in molds and forms. You can also buy a form of spray on plastic to coat items with plastic.

I have also seen liquid foam. When you spray it, it fluffs up into a foam like substance. I use it to fill in the space under my patio enclosure and keep out water.