A synonym often used for plastic is the word Polymer. Polymer is derived from the Greek words �poly� and �meros� meaning a group of many units. It includes all plastics as well as many biological and inorganic materials. Well known examples of polymers include plastics, DNA and proteins.
Polymers can be classified according to its properties under different circumstances. One commonly used classification is based on the behaviour of the materials in heated environment and it can be categorized into either thermoplastics or thermosetting plastics. The key difference between them is that thermoplastics become soft, remoldable and weldable when heat is added. Thermosetting plastics, on the other hand, can not be welded or remolded but simply burning instead.
Most thermoplastic polymers can be recycled from their initial use as a consumer, business, or industrial product back into a raw material that is used in some other products� manufacture process. In contrast, thermosetting polymers can only be recycled for use as inert filler in another material. Often, recyclable thermoplastic polymers are classified as Post-Industrial or Post-Consumer based on the sources. Post-Industrial includes manufacturing scrap, containers and industrial packaging. Post-Consumer includes any plastic products that passed through the hands of a consumer such as plastic bags, beverage containers, carpeting, home appliances, toys and etc.
Here, we provide six specific numbered categories of recyclable plastics with a generic seventh for �other�:
| Image | Material |
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1. PET (polyethylene terephthalate) - Beverage containers (2-liter soda bottles), boil-in food pouches, processed meat packages, etc. |
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2. HDPE (high density polyethylene) - Milk bottles, detergent bottles, oil bottles, toys, plastic bags |
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3. PVC (polyvinyl chloride) - Food wrap, vegetable oil bottles, blister packaging |
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4. LDPE (low density polyethylene) - Shrink-wrap, plastic bags, garment bags |
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5. PP (polypropylene) - Margarine and yogurt containers, grocery bags,caps for containers, carpet fiber, food wrap. |
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6. PS (polystyrene) - Plastic utensils, clothes hangars, foam cups and plates |
| NO IMAGE | 7. Other (all other polymers and polymer blends) - including polycarbonate, ABS, PPO/PPE |
For an abbreviation list of polymer:
http://www.theotherpages.org/poly-faq.html#abbrev