What are the properties of commonly used plastics?

PE is a polyethylene plastic, with stable chemical properties, usually made into food bags and various containers, resistant to acid, alkali and salt aqueous solution, but should not be wiped or soaked with strong alkaline detergent.

PP is a polypropylene plastic, non-toxic, tasteless, can be soaked in boiling water of 100 without deformation, no damage, common acid, alkali organic solvents have almost no effect on it. It is mostly used for tableware.

PS is a polystyrene plastic, easy to color, good transparency, mostly used to make lampshades, toothbrush handles, toys, electrical parts. It is resistant to acid and alkali corrosion, but is easily soluble in organic solvents such as chloroform, dichloroethylene, and banana water.

PVC is polyvinyl chloride plastic, bright color, corrosion resistance, firm and durable, due to the addition of plasticizers, anti-aging agents and other toxic auxiliary materials in the manufacturing process, so its products generally do not store food and medicine.

ABS is a plastic polymerized by acrylonitrile, butadiene and styrene, which is eye-catching, heat-resistant, strong, and the outer surface can be plated with chrome, nickel and other metal films, which can be used to make piano keys, buttons, knife holders, TV shells, umbrella handles, etc.

PA is a nylon plastic, which is tough, firm and wear-resistant, and is often used to make combs, toothbrushes, clothes hooks, fan bones, mesh bag ropes, fruit packaging bags, etc. It is non-toxic, but it should not be in long-term contact with acids and bases.

The performance of plastics includes mechanical properties, chemical properties, electrical properties, optical properties, etc., and the use is divided into many kinds.

Commonly used plastic types are: polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS) and acrylonitrile, butadiene styrene styrene copolymer (ABS).

1.Polyethylene.

Polyethylene plastic is soft, waxy to the touch, lighter than comparable plastics, has a certain degree of transparency, and has a blue flame when burning. The main application areas are: plastic wrap, vest plastic bags, plastic food bags, feeding bottles, pails, kettles, etc.

2.Polypropylene.

Polypropylene is a thermoplastic resin made by polymerization of propylene, which is a white waxy material with a transparent and light appearance. The density is dense, flammable, melting point 165, softened at about 155, and the operating temperature range is -30 140 It is mainly used in household appliances injection parts, modified raw materials, daily injection products, pipes, etc.

3.Polyvinyl chloride.

PVC used to be the world's largest general-purpose plastic, an amorphous polymer with no obvious melting point and plasticity when heated to 120 150. The application is very wide. It is widely used in building materials, industrial products, daily necessities, floor leather, floor tiles, artificial leather, pipes, wires and cables, packaging films, bottles, foam materials, sealing materials, fibers, etc.

4.Polystyrene.

Polystyrene is a thermoplastic resin that is a shiny, transparent beaded or granular solid. Density, transparency 88% 92%, refractive index. It is widely used in optical instruments, chemical industry and daily necessities, and is used to make tea trays, sugar tanks, soap boxes, cigarette boxes, student rulers, combs, etc.

Due to its certain air permeability, when made into film products, it can be used as a good food packaging material.

5. abs

ABS plastic is a terpolymer of acrylonitrile (A)-butadiene (B)-styrene (S). It combines the properties of three components, among which acrylonitrile has high hardness and strength, heat resistance and corrosion resistance; Butadiene is impact resistant and tough; Styrene has a high gloss surface, easy colorability and ease of processing. The characteristics of the above three components make ABS plastic a thermoplastic with good comprehensive performance of "toughness, toughness and rigidity".

ABS is electrically insulating and virtually unaffected by temperature, humidity and frequency, making it suitable for use in most environments. The largest application areas of ABS resin are automobiles, electrical and electronics, and building materials.

1. Plastics are malleable.

As the name suggests, it is a material that can be used to shape. This plasticity means that the solid plastic can be softened by heating, and then it is cooled in a sexual mold to make it appear in a new shape. But it has certain defects in this property, that is, it is easy to deform when heated, especially some plastics are deformed when scalded with boiling water, so plastics generally do not come into contact with boiling water.

2. Plastics are elastic.

Some plastics are like fiber-synthesized ones that have a certain amount of elasticity. When it is pulled artificially, its body will deform, but when the pull force is zero, it will return to its original form, which makes it elastic. If some plastics are not elastic, that's a different story.

3. Plastic has high strength.

Although plastic is not so hard compared to metal, it is still comparable to glass, ceramics and wood, and it has relatively high strength and wear resistance, which can be used to make strong gears and bearings on machines.

4. Plastic has corrosion resistance.

Plastic will not rust, nor will it be rotted or attacked by microorganisms in a very humid environment, and it can also resist acid and alkali corrosion, so it is often used as water and infusion pipelines, doors and windows in chemical plants.

5. Plastics are insulating.

Plastic is not conductive (is insulated) is determined by its internal structure, so it has insulation, and is often used to make wire skins, socket boards, electrical shells and so on.

Chongqing Professional Scrap Iron ** Network :

The properties of plastic products can vary according to factors such as their composition, processing technology, and use, but generally speaking, plastic products have the following properties:

Physical properties: The physical properties of plastic products include density, hardness, strength, toughness, wear resistance, weather resistance, waterproofness, corrosion resistance, etc. Different kinds of plastic products have different physical properties, and can be selected according to actual needs.

Chemical properties: Plastic products have chemical stability and chemical corrosion resistance, and can resist the erosion of acids, alkalis, salts and various chemicals.

Thermal properties: The thermal properties of plastic products include thermal stability, heat deflection temperature, thermal conductivity, expansion coefficient, etc. Different types of plastic products perform differently at high temperatures.

Optical properties: Plastic products have optical transparency, optical waveguide properties, optoelectronic properties, etc., and can be used in optical devices, displays, sensors and other fields.

Electrical properties: Plastic products have electrical properties such as insulation properties, dielectric constant, and dielectric loss, and can be used in electric stool components, electrical equipment and other fields.

Environmental performance: Plastic products have environmental performance, can be utilized, degraded and decomposed.

It should be noted that different types and brands of plastic products have different performance characteristics, and suitable plastic materials and products should be selected according to the actual needs and use environment to ensure their normal use and best performance. At the same time, it is necessary to comply with relevant safety norms and standards in the process of production and use to avoid harm to the human body and the environment.

Plastics can be divided into two categories: general plastics and engineering plastics according to their performance and use.

1. General plastics refer to plastics for general purposes, which have a wide range of uses, large output, and low output, and are the most widely used plastics in construction.

2. Engineering plastics refer to polymers with high mechanical strength and other special properties.

Plastics can be divided into two categories: thermoplastics and thermosetting plastics according to their different thermal properties.

1. Thermoplastics are softened or melted when heated, hardened and shaped after cooling, and no chemical changes occur in the process of cold and heat, and no matter how many times they are heated and repeated, this property is maintained, so the processing and molding are simple and have high mechanical properties, but the heat resistance and rigidity are poor.

The resins in thermoplastics are all linear molecular structures, including all polymeric resins and partial condensation resins, and their typical varieties are polyethylene, polypropylene, polystyrene, polyvinyl chloride, polymethyl methacrylate, ABS plastics, polyamide, polyoxymethylene, polycarbonate, polyphenylene ether, etc.

2. In the process of processing, thermosetting plastics are first softened by heat, and then solidified, and can no longer be softened after hardening, chemical changes occur during the processing process, and adjacent molecules are cross-linked with each other to form a body structure and harden into an insoluble substance, its heat resistance and stiffness are good, but the strength of the machine is low.