Zhejiang Shifang Pipe Industry Co.,Ltd

Zhejiang Shifang Pipe Industry Co.Ltd is one of the most professional manufacturer and exporter of roof drainage system..

Home > News > Content
Five Major Plastics.
- Aug 16, 2018 -

Plastic is a kind of polymer compound which is polymerized by adding or condensation of monomer. It is commonly called plastic or resin. It can change its composition and shape freely. It is composed of synthetic resin, filler, plasticizer, stabilizer, lubricant, pigment and other additives. Plastics are mainly composed of resins. Resin accounts for about 40% to 100% of the total weight of plastic. The basic properties of plastics are mainly determined by the nature of resins, but additives also play an important role. Some plastics are basically composed of synthetic resins, without or without additives, such as plexiglass, polystyrene and so on.


Polyethylene is the most productive variety in the plastics industry. Polyethylene is a thermoplastic resin obtained from ethylene polymerization. In industry, ethylene and a small number of alpha olefin copolymers are also included. Polyethylene is odorless, non-toxic, waxy, with excellent low-temperature resistance (the lowest operating temperature can reach - 100 ~ - 70 degree C), good chemical stability, can resist most of the acid-base erosion (not resistant to oxidizing acid). At room temperature, it is insoluble in general solvents. It has small water absorbency and excellent electrical insulation. Polyethylene is generally used in preservative film, vest-type plastic bags, plastic food bags, bottles, buckets, kettles and so on.


PE products


Polypropylene is a thermoplastic resin prepared by polymerization of propylene. Polypropylene is a non-toxic, odorless, tasteless, milky white high-crystalline polymer with a density of only 0.90-0.91 g/cm 3. It is one of the lightest plastics at present. It is especially stable for water. Its water absorption in water is only 0.01%, and its molecular weight is about 8 in case of 150 thousand. Good formability, but because of the large shrinkage (1% ~ 2.5%). Thick-walled products are easy to be sunken, for some parts with high dimensional accuracy, it is difficult to meet the requirements, the product surface gloss is good. Polypropylene is commonly used in microwave oven, tableware, basin, plastic barrel, thermos bottle shell, woven bag and so on.


PP products


Polyvinyl chloride (PVC) is an initiator of vinyl chloride monomer, such as peroxide and azo compound, or a polymer polymerized by free radical polymerization under the action of light and heat. Stabilizer, lubricant, auxiliary processing agent, pigment, impact resistance agent and other additives are often added to PVC materials in practical use. It has no flammability, high strength, weather resistance and excellent geometric stability. PVC is commonly used in plastic wrap, plastic shoes and leather products, films, cables, plastic bags.

Particular attention: PVC made of plastic film, plastic bags and other soft plastic, must be added to a large number of auxiliary materials, some are toxic, harmful substances in this material released may cause cancer.


PVC products


Polystyrene is a kind of colorless and transparent thermoplastic which is synthesized by free radical polymerization of styrene monomer. It has a glass transition temperature higher than 100 C. Therefore, it is often used to make disposable containers which need to bear boiling water and disposable foam lunch boxes. In addition, polystyrene is also used in combs, boxes, ball-point pens, children's toys, plastic shopping bags and so on.

Special attention: the production of disposable tableware will be a large number of heavy metals and other prohibited additives, and food containing water, vinegar, oil and other mutual dissolution, into the human body, may cause indigestion, local pain and liver diseases.


PS products


ABS is acrylonitrile butadiene styrene copolymer. ABS is a thermoplastic polymer material with high strength, good toughness and easy fabrication. ABS resin is acrylonitrile, 1, 3- butadiene, styrene copolymer of three yuan. It can behave normally in the environment of - 25 ~60, and has good formability. The surface of the product is smooth, easy to dye and plating. It can be blended with various resins to blend. ABS is mainly used in alloys, plastics, and ABS grades.