How to distinguish between four common plastic materials

- Nov 19, 2018-

How to distinguish between four common plastic materials: 

Bussing box Plastic dish collection box

polyethylene (PE), polyvinyl chloride (PVC), polypropylene (PP), polystyrene (PS) What is the difference?

Common industrial plastic materials: polyethylene (PE), polyvinyl chloride (PVC), polypropylene (PP), polystyrene (PS) have different chemical properties and are used in product production.

Polypropylene, referred to as PP.

A thermoplastic resin obtained by polymerizing propylene.

It is white translucent when uncolored, waxy; lighter than polyethylene. Transparency is also better than polyethylene (PE) and harder than polyethylene (PE).

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

Polyethylene, referred to as PE.

It is a polymer of ethylene and is non-toxic. Easy to color, good chemical stability, cold resistance, radiation resistance, electrical insulation. It is suitable for packaging materials for food and medicine, making utensils, medical equipment, and insulating materials for the electronics industry.


Polyvinyl chloride, referred to as PVC.

It is a polymer of vinyl chloride. Polyvinyl chloride (PVC) is a synthetic material with many advantages and is an ideal material for engineering plastics.

Good chemical stability, acid, alkali and some chemicals.

Resistant to moisture, aging, and flame retardant. When used, the temperature should not exceed 60 ° C, and it will harden at low temperatures.

Polyvinyl chloride is divided into soft plastic and hard plastic. The soft type is mainly made into a film, which is used as a packaging material, a rainproof article, an agricultural seedling film, etc., and can also be used as an insulating layer of a cable or a wire, and an artificial leather product. Rigid, generally made of tubing and sheeting, used as a water pipe and transporting corrosion resistant fluid pipes, which are used as linings and floors for various tanks.

Other related: the color is yellowish translucent and shiny. Transparency is better than polyethylene, polyphenylene, worse than polystyrene. It is divided into soft and hard polyvinyl chloride according to the amount of additives. The soft products are soft and tough, and the hand feels sticky. The hardness of hard products is higher than that of low density polyethylene. However, below polypropylene, whitening occurs at the bend. Common products: plates, pipes, soles, toys, doors and windows, wire sheaths, stationery, etc.

Polystyrene, referred to as PS.

Transparent when not colored. The product is grounded or beaten, with a metal-like crisp sound, good gloss and transparency. Similar to glass, it is brittle and easy to break. Fingernails can be used to mark the surface of the product. The modified polystyrene is opaque. Common products: stationery, cups, food containers, home appliance casings, electrical accessories, etc.