Description of the problem:
The first time I came into contact with the word PS is in Shantou sewage treatment plant opposite the refinery, the intersection reads: "PS car entrance".
Recently bought a Japanese original imported up to 1/100MD assembly model, the box is written: "Manufacturing materials: PS, PE, ABS, PET, PP, PVC, POM", inside the parts are also printed: "Manufacturing materials: PS" or "Manufacturing materials: PE", "Manufacturing materials: ABS". Here to ask, what is PS, PE, ABS, PET, PP, PVC, POM.
Ans:
PS: polyphenylene ethylene
is a colorless transparent plastic material. It has a glass transition temperature higher than 100 degrees Celsius, so it is often used to make a variety of disposable containers that need to withstand the temperature of boiling water, as well as disposable foam lunch boxes.
zh. *** /wiki/Image:Polystyrene.png
PP: Polypropylene
is a semi-crystalline thermoplastic. It has high impact resistance, strong mechanical properties, and is resistant to many organic solvents and acids and alkalis. It has a wide range of applications in industry and is one of the usual common polymer materials. Australia's coins also use polypropylene production.
Structure: zh. *** /wiki/Image:Polypropylene_structure.png
PE: Polyethylene
It is one of the most commonly used polymer materials in daily life, and is used in large quantities in the manufacture of plastic bags, plastic film, and milk pail products.
Polyethylene is resistant to a wide range of organic solvents, and to corrosion by a variety of acids and alkalis, but is not resistant to oxidizing acids, such as nitric acid. Polyethylene is oxidized in oxidizing environments.
Polyethylene can be considered transparent in the thin film state, but when present in bulk form it is opaque due to the large number of crystals present within it, which can cause strong light scattering. The degree of crystallization of polyethylene is influenced by the number of branched chains, the more branched the chains, the more difficult it is to crystallize. The melting temperature of polyethylene crystals is also affected by the number of branch chains and ranges from 90 degrees Celsius to 130 degrees Celsius, with the more branch chains the lower the melting temperature. Polyethylene single crystals can usually be prepared by dissolving high-density polyethylene in xylene at temperatures above 130 degrees Celsius.
Structural formula: - CH2 - CH2 - CH2 - CH2 - CH2 - CH2 - CH2 - CH2 - CH2
ABS: a synthetic plastic of acrylonitrile, butadiene, styrene
Acrylonitrile, butadiene, styrene, three monomers of the grafting *** polymerization products, take the first letter of their English names. It is a high strength, good toughness, excellent overall performance of the resin, a wide range of uses, commonly used as engineering plastics. Industry to polybutadiene latex or styrene content of low styrene rubber main chain, and acrylonitrile, styrene two monomers of the mixture of graft **** polymerization made. In fact, it is often a mixture of butadiene-containing graft polymers and acrylonitrile-styrene **** polymer SAN (or AS). In recent years, there are also first styrene, acrylonitrile two monomer *** polymerization, and then with the graft *** polymerization of ABS resin to different proportions of the mixture, in order to produce to adapt to the different uses of a variety of ABS resins. 1950s has begun in the United States industrial production.
Industrial production methods can be divided into two categories: one is the polybutadiene or SBR and SAN resins in the roller for mechanical **** mixing, or two kinds of latex **** mixing, and then **** polymerization; the other is in the polybutadiene or styrene content of low butadiene latex to add styrene and acrylonitrile monomers for the emulsion grafting **** polymerization, or then mixed with SAN resins in different proportions.
Structure, Properties and Applications In ABS resin, the rubber particles are in a dispersed phase, dispersed in the continuous phase of SAN resin. When impacted, the crosslinked rubber particles withstand and absorb this energy, dispersing the stress and thus preventing the development of cracks, thus improving tear resistance.
The purpose of graft*** polymerization is to improve the compatibility and adhesion of the rubber granule surface to the resin phase. This is related to the amount of free SAN resin and the composition of the SAN resin grafted onto the rubber main chain. The difference between the acrylonitrile content of these two resins should not be too large, otherwise the compatibility is not good, which will lead to cracking of the interface between the rubber and resin.
ABS resin can be used in injection molding, extrusion, vacuum, blow molding and roller pressing molding method for plastic processing, but also available machinery, bonding, coating, vacuum vaporization and other methods for secondary processing. Because of its excellent overall performance, a wide range of uses, mainly used as engineering materials, can also be used for household appliances. Because of its oil resistance and resistance to acids, alkalis, salts and chemical reagents and other good performance, and can be plated, plated with a metal layer has a good luster, light weight, low price and other advantages, can be used to replace some of the metal. Can also synthesize self-extinguishing and heat-resistant type and many other varieties to adapt to a variety of uses.
PET: polyethylene terephthalate
Polymer of terephthalic acid and ethylene glycol. Abbreviated as PET, it is mainly used in the manufacture of polyethylene terephthalate fibers (Chinese trade name polyester). This fiber has high strength, its fabric wearing performance is good, is currently the highest production of synthetic fibers in a variety of world production in 1980 about 5.1 million tons, accounting for 49% of the world's total output of synthetic fibers
Properties of molecular structure of the high degree of symmetry and the rigidity of the chain of the phenylene, so that the polymer has a high degree of crystallinity, high melting temperature and insoluble in organic solvents in general, the melt temperature is 257 ~ 265 ℃; the polymer is mainly used to manufacture polyethylene terephthalate fiber (Chinese commercial name of polyester.). is 257～265℃; its density increases with the increase of crystallinity, the density of amorphous state is 1.33 g/cm^3, after stretching due to the increase of crystallinity, the density of fibers is 1.38～1.41 g/cm^3, from the X-ray study, the density of the complete crystalline was calculated to be 1.463 g/cm^3. The glass transition temperature of the amorphous polymer is 67℃; the crystalline polymer is 81°C. The polymer has a heat of fusion of 113-122 J/g, a specific heat capacity of 1.1-1.4 J/(g. K), and a dielectric constant of 1.1-1.4 J/(g. K). The specific heat capacity is 1.1-1.4 J/(g. K), the dielectric constant is 3.0-3.8, and the specific resistance is 10^11 10^14 ohm. cm. PET is not soluble in common solvents, only in some corrosive organic solvents such as phenol, o-chlorophenol, m-cresol, trifluoroacetic acid mixed solvents, PET fiber is stable to weak acids and weak bases.
Application Mainly used as raw materials for synthetic fibers. Staple fibers can be blended with cotton, wool, hemp, made of textiles for clothing or interior decorative fabrics; filament can be made of clothing or industrial filaments, such as for filter fabrics, tire cord, parachute, conveyor belts, seat belts and so on. The film can be used as the base for photographic film and cassette tape. Injection molded parts can be used as packaging containers.
PVC: Polyvinyl Chloride
is a polymer material that uses a chlorine atom to replace a hydrogen atom in polyethylene.
The most important characteristic of polyvinyl chloride is that it is flame retardant, so it is widely used in fire prevention applications. However, polyvinyl chloride releases hydrochloric acid and other toxic gases during combustion.
Structural formula: - CH2 - CHCl - CH2 - CHCl - CH2 - CHCl -
POM: Polyoxymethylene
The scientific name is polyoxymethylene, a thermoplastic crystalline polymer. Abbreviation for POM. structural formula for CH - O, 1942 years ago, formaldehyde polymerization is mostly polymerization is not high, easy to heat depolymerization of polyoxymethylene glycol HO CH O H, of which = 8 ~ 100 for the polyformaldehyde; more than 100 for the - polyformaldehyde, around 1955, the U.S. DuPont polymerization of formaldehyde from the formaldehyde homopolymer, that is, homopolymer, commercial name homopolymer. The U.S. Celanese company by the start of the triple formaldehyde, made with a small amount of dioxin pentacyclic or ethylene oxide *** polymer, that is, *** polyformaldehyde, trade name Celcon.
Properties of polyformaldehyde is very easy to crystallize, the degree of crystallinity of 70%; through high-temperature annealing, the degree of crystallinity can be increased. The melting temperature of paraformaldehyde is 181°C and its density is 1.425 g/cm . *** The melting point of paraformaldehyde is about 170℃. The glass transition temperature of homopolyformaldehyde is -60℃. Phenolic compounds are the best solvents for paraformaldehyde. It is known from the study of melt index that the molecular weight distribution of homopolyformaldehyde is narrow. Except for strong acids, oxidizing agents and phenols, ***Polyformaldehyde is stable to other chemicals, while homopolyformaldehyde is also unstable to concentrated ammonia. Stabilized paraformaldehyde can be heated to 230°C without significant decomposition. Polyformaldehyde can be used in compression, injection, extrusion, blow molding and other methods of molding, processing temperature of 170 ~ 200 ℃; can also be processed by machine tools, can also be welded. Products are light, hard, rigid and elastic, dimensionally stable, small coefficient of friction, low water absorption, good insulation properties, and resistance to organic solvents; can be used in a wide range of temperatures (-50 ~ 105 ° C) and humidity range; in a variety of solvents and chemical reagents, as well as large loads and long periods of cyclic stress to maintain unchanged performance.