Common Recycled Plastic Features and Applications

Polyethylene PE

When it is not colored, it is milky-white translucent and waxy; hand-feeling products have a creamy feeling, soft and tough; slightly stretched. General low-density polyethylene is softer and has better transparency; high-density polyethylene is harder.

Common products: handbags, water pipes, oil drums, beverage bottles (calcium milk bottles), daily necessities, etc.

Polypropylene PP

It is white translucent and waxy when not painted; lighter than polyethylene. The transparency is also better than polyethylene and harder than polyethylene.

Common products: pots, barrels, furniture, films, woven bags, bottle caps, car bumpers, etc.

Polystyrene PS

Transparent when not colored. The product is grounded or knocked, with metal-like crisp sound, shiny and transparent, similar to glass, brittle and easy to break, and the fingernail can mark the surface of the product. Modified polystyrene is opaque.

Common products: stationery, cups, food containers, home appliances, electrical accessories, etc.

PVC PVC

The color is slightly yellow translucent and shiny. The transparency is better than that of polyethylene, polyphenylene, and polystyrene, and it is divided into soft and rigid polyvinyl chloride, and the soft product is soft and tough, and the hand feels sticky. The hardness of the hard product is higher than that of the low density polyethylene. However, below the polypropylene, whitening occurs at the inflection point.

Common products: plates, pipes, soles, toys, doors and windows, wire sheaths, stationery, etc.

Polyethylene terephthalate PET

The transparency is very good, the strength and toughness are better than those of polystyrene and polyvinyl chloride, and they are not easily broken.
Common products: often bottle products such as cola, mineral water bottles, etc.

Polyethylene waste

Polyethylene is the largest plastic in plastics and is used in a wide range of thermoplastics. It is made of ethylene and is a partially crystalline material. It can be processed by the molding method of general thermoplastics. Polyethylene can be divided into high-density polyethylene, low-density polyethylene and linear low-density polyethylene three categories.

The density of high-density polyethylene is generally higher than 0.94 g/, while the density of low-density polyethylene and linear low-density polyethylene is between 0.91 and 0.94 g/cm. There are two main sources of waste polyethylene film:

1. Offsets, defective products, etc. produced in film production. These wastes are clean and clearly categorized. They can be crushed, compressed, and sent directly to the extruder for pelletizing. The recycling process is simpler.

2. Waste films from the chemical industry, electrical industry, food and consumer goods industries. These waste films have been contaminated, some have been colored and printed with trademarks, and some contain impurities such as sand, sawdust or shredded paper.
Polyethylene is widely available because of its low cost and easy availability, but it is still the most widely used packaging product, estimated at 60% or more. High-density polyethylene is mainly used for packaging films and bottles, hollow containers; the main purpose of low-density polyethylene is packaging film and agricultural film; linear low-density polyethylene is mainly used for film, film plastic parts, pipe And on the wire and cable.

PVC waste

Polyvinyl chloride has historically used the largest amount of plastic, and is now being replaced by polyethylene and PET in some areas, but it is still in heavy use. Its consumption is second only to polyethylene and polypropylene. PVC products are very rich in forms and can be divided into three categories: hard PVC, soft PVC, and PVC paste. Hard PVC is mainly used for extruded products such as pipes, window profiles, and sheet materials, as well as injection molded parts such as pipe joints and electrical parts, and extrusion blow-type bottles, which account for about 65% of the consumption of polyvinyl chloride. Soft PVC is mainly used in calendered films, car accessories, handbags, films, labels, wire and cable, and medical products. Polyvinyl chloride paste accounts for about 10% of PVC products, mainly used products such as plastic products.

Polymethyl methacrylate waste

Polymethyl methacrylate (PMMA) is commonly known as plexiglass. PMMA has unique properties that other plastics do not have: excellent transparency (close to glass); toughness, chemical resistance, and weatherability are all good. Therefore, it has been widely used in automobiles, medical equipment, indoor swimming pools, etc. With the development of related industries such as automobiles, the amount of PMMA is also increasing. There are mainly three types of PMMA products: sheets made by casting or extrusion; specific products that already contain modifiers, pigments, and other additives; paints and coatings.

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