How to Melt Scrap Plastic
- 1). Cut scrap water bottles into about one-inch square fragments. Scissors will cut though the bottle, however the bottle cap and threaded bottle opening may be thicker and stronger. These parts may be discarded.
- 2). Gather the shredded scrap plastic pieces into the metal can and fill halfway. Remove the can's label.
- 3). Cover the opening of the metal can with aluminum foil to prevent the plastic from oxidizing in the presence of air.
- 4). Place the finished can assembly into an oven set to 220 to 270 degree. Polyethylene usually melts over this range, depending on the exact polymerization geometry of the ethylene molecules.
- 5). Melt the plastic. This process may take a few hours depending on the mass of the plastic to be melted. Do not use excessive heat, which would damage the plastic. When the plastic liquefies, it will take the shape of its container, which is the shape of the can in this case.
- 6). Turn off the oven. Allowing the experiment time to cool gradually will allow the molecules of polyethylene to crystallize. As a result, the plastic will appear white and opaque. If the molten plastic is cooled rapidly, the plastic will be frozen into a "glassy" transparent state.
- 7). Turn the can upside down. Pry out the solidified and cooled plastic. The can might need to be cut apart to release the plastic. In this case, use sheet metal cutters and wear gloves.
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