The code below is called the SPI resin identification coding system, developed by the American Society of the Plastics Industry in 1988.

Most plastics can be recycled, but because of the difficulty and expense of sorting, collecting, cleaning and reprocessing it is only at the moment economically viable to recycle PETE, PVC and HDPE.

Thermoplastics can be remelted, but thermosetting plastics can only be crushed and used as insulation.

As you can not mix plastics together they have to be separated into their different polymer types.

Recycling No. Abbreviation Polymer Name
1 PETE or PET Polyethylene Terephthalate
2 HDPE High-Density Polyethylene
3 PVC or V Polyvinyl Chloride
4 LDPE Low-Density Polyethylene
5 PP Polypropylene
6 PS Polystyrene
7 OTHER Other plastics, including acrylic and nylon.

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