Plastic is a polymer organic material with resin as the main component, which can be molded into a certain shape at a certain temperature and pressure, and can maintain the established shape at room temperature.
Resin refers to an organic polymer, which usually has a certain transformation or melting range when heated, and is transformed into a fluid under the action of external force, and is solid or semi-solid or liquid at room temperature. It is the most basic and important component in plastics. Broadly speaking, any polymer as the basic material of plastics in the plastic industry can be called resin.
Second, the classification of plastics
At present, there is no exact classification of plastics, which is roughly as follows: 1. According to the physical and chemical properties of plastics, thermoplastics: plastics that can be softened by repeated heating and hardened by cooling within a specific temperature range. Such as polyethylene plastic and polyvinyl chloride plastic.
Thermosetting plastics: plastics that solidify into insoluble materials due to heat or other conditions. Such as phenolic plastics, epoxy plastics and the like.
2. According to the use of plastic, choose a point.
General plastics:-Generally refers to plastics with large output, wide use, good formability and low price. Such as polyethylene, polypropylene, polyvinyl chloride, etc.
Engineering plastics:-Generally, it refers to plastics that can bear certain external forces, have good mechanical properties and dimensional stability, and can still maintain its excellent properties at high and low temperatures, and can be used as engineering structural parts. Such as ABS, nylon, alum and so on.
Special plastics:-Generally refers to plastics with special functions (such as heat resistance, self-lubrication, etc.). ) and applied to special requirements. Such as fluoroplastics and silicones.
3. According to the plastic molding method
Molded plastic: a mixture of resins used for molding. Such as ordinary thermosetting plastics.
Laminated plastics: refers to the fiber fabric impregnated with resin, which can be laminated and hot-pressed to form an integral material.
Injection, extrusion and blow molding of plastics: generally speaking, it refers to the resin mixing part that can melt and flow at the temperature of the barrel and harden rapidly in the mold. Such as ordinary thermoplastics.
Casting: a liquid resin mixture that can be poured into a mold without pressure or with a little pressure and hardened into a certain shape. Such as MC nylon.
Reaction injection molding compound: Generally speaking, it refers to the liquid raw material that is injected into the mold cavity under pressure to make it react and solidify to make the finished product. Such as polyurethane.
4. According to the plastic semi-finished products and finished products
Modeling powder: also known as plastic powder, it is mainly made of thermosetting resin (such as phenolic resin) and filler through full mixing, pressing and crushing. Such as phenolic plastic powder.
Reinforced plastic: a kind of plastic whose material is reinforced and some mechanical properties are greatly improved compared with the original resin.
Foam: Plastic with many micropores on the whole.
Film: generally speaking, it refers to flat and soft plastic products with a thickness below 0. 2525mm. ..
Third, the basic properties of plastics
1. Light weight and high specific strength. Plastics are light, and the density of general plastics is between 0.9 and 2.3g/cm3, only about 1/8 ~ 1/4 for steel and 1/2 for aluminum, while the density of various foamed plastics is lower, about 0.0 1 ~ 0.5g/cm3. The strength calculated by unit mass is called specific strength, and the specific strength of some reinforced plastics is close to or even exceeds that of steel. For example, the tensile strength per unit mass of alloy steel is 160 MPa, while the glass fiber reinforced plastic can reach 170~ 400 MPa.
2. Excellent electrical insulation performance. Almost all plastics have excellent electrical insulation properties, such as extremely small dielectric loss and excellent arc resistance, which are comparable to ceramics.
3. Excellent chemical stability. Generally speaking, plastics have good corrosion resistance to chemicals such as acid and alkali. In particular, PTFE has better chemical corrosion resistance than gold, and even can resist the corrosion of highly corrosive electrolytes such as aqua regia, so it is called "the king of plastics".
4. Good antifriction and wear resistance. Most plastics have excellent antifriction, wear resistance and self-lubricating properties. Many antifriction parts made of engineering plastics make use of these characteristics of plastics. Adding some solid lubricants and fillers to wear-resistant plastics can reduce its friction coefficient or further improve its wear resistance.
5. Light transmittance and protective performance. Most plastics can be used as transparent or translucent products, among which polystyrene and acrylate plastics are as transparent as glass. The chemical name of plexiglass is polymethyl methacrylate, which can be used as aviation glass material. Plastic films such as polyvinyl chloride, polyethylene and polypropylene have good light transmittance and warmth retention, and are widely used as agricultural films. Plastic has many protective properties, so it is often used as protective articles, such as plastic films, boxes, barrels, bottles and so on.
6. Excellent damping and silencing performance. Some plastics are flexible and elastic. When they are subjected to frequent mechanical shocks and vibrations from the outside, viscous internal friction will occur inside, which will convert mechanical energy into heat energy. Therefore, they are used as damping and silencing materials in engineering. For example, bearings and teeth made of engineering plastics can reduce noise, and various foamed plastics are widely used as excellent damping and silencing materials.
The excellent properties of the above plastics make them widely used in industrial and agricultural production and people's daily life; It has become an indispensable material in modern life and cutting-edge industries from the past as a substitute for materials such as metal, glass, ceramics, wood and fiber.
However, plastics also have disadvantages. For example, the heat resistance is worse than that of metals and other materials. General plastics can only be used below 100℃, and a few are used around 200℃. The thermal expansion coefficient of plastics is 3~ 10 times larger than that of metals, and it is easily affected by temperature changes. Under the load, the plastic will slowly flow or deform, that is, creep phenomenon; In addition, plastics will age under the action of atmosphere, sunlight, long-term pressure or some substances, which will make their properties worse. These shortcomings of plastics more or less affect or limit its application. However, with the development of plastic industry and the in-depth study of plastic materials, these shortcomings are being gradually overcome, and new plastics and various plastic composite materials with excellent performance are constantly emerging.
Fourth, the use of plastics.
Plastics have been widely used in agriculture, industry, architecture, packaging, cutting-edge national defense industry and people's daily life.
Agriculture: A lot of plastics are used to make plastic films, seedling films, greenhouse films, irrigation and drainage pipes, fishing nets, breeding floats and so on.
Industry: Plastic is widely used in electrical and electrical industries to make insulation materials and packaging materials; In the mechanical industry, transmission gears, bearings, bearing shells and many parts are made of plastic instead of metal products; In the chemical industry, plastics are used as pipes, containers and other anticorrosion materials; In the construction industry, it is used as doors and windows, stair handrails, floor tiles, ceilings, heat insulation and sound insulation boards, wallpaper, falling pipe fittings and pit pipes, decorative boards, sanitary wares, etc.
In the national defense industry and cutting-edge technology, plastics are indispensable materials for conventional weapons, airplanes, warships, rockets, missiles, artificial satellites, spacecraft and atomic energy industries. In people's daily life, plastics are widely used, such as plastic sandals, slippers, raincoats, handbags, children's toys, toothbrushes, soap boxes, thermos shells and so on. At present, it has been widely used in various household appliances, such as TV sets, tape recorders, electric fans, washing machines, refrigerators and so on.
As a new packaging material, plastic has been widely used in the packaging field, such as various hollow containers, injection containers (turnover boxes, containers, barrels, etc. ), packaging film, woven bag, corrugated box, foam plastic, lashing rope, bandage.
Verb (abbreviation of verb) The development history and present situation of plastic industry.
As early as19th century ago, people have used natural resins such as asphalt, rosin, amber and shellac. 1868, natural cellulose was nitrated, camphor was used as plasticizer, and the world's first plastic variety, called celluloid, was made, and the history of human using plastics began. Since then, the history of human use of plastics has begun. 1909, the first synthetic plastic-phenolic plastic appeared. 1920, another synthetic plastic-amino plastic (aniline formaldehyde plastic) was born. These two kinds of plastics have played a positive role in promoting the development of electrical appliance industry and instrument manufacturing industry.
In the 1920s and 1930s, alkyd resin, polyvinyl chloride, acrylate, polystyrene and polyamide appeared one after another. Since the 1940s, with the development of science, technology and industry, as well as the extensive development and utilization of petroleum resources, the plastic industry has developed rapidly. There are many kinds, such as polyethylene, polypropylene, unsaturated polyester, fluoroplastics, epoxy resin, polyformaldehyde, polycarbonate, polyimide and so on. Questions and answers on basic knowledge of waste plastics
1. What is PPC plastic and how to identify it from its appearance?
Reply: PPC belongs to PP, called chlorinated polypropylene, which is used to make daily necessities and electrical appliances.
I broke the waste plastic. What is the price of waste plastics now (2004- 1 1-9)?
Reply: polypropylene material (woven bag): 1200- 1600 yuan/ton; Polypropylene material (pot material): 2 100-2600 yuan/ton; Polyethylene (soft material): 2300-3300 yuan/ton; Polyethylene (hard material): 2700-3800 yuan/ton; PVC: 2500-3 100 yuan/ton; Foam: 2000-3300 yuan/ton; Polyester (mineral water bottle): 5000-5800 yuan/ton; (Disclaimer: The data provided are for reference only, please refer to the quotation date. )
3. What kind of raw materials are used to produce HDPE gas pipes and water supply pipes?
Reply: The raw materials for producing HDPE gas pipes and water supply pipes are PE80 and PE 100.
4. What material is 4.PPN?
Reply: PPN is a kind of polypropylene.
5. Where is the most flexible EVA at present?
Reply: EVA made in China is basically made in Beijing, which is divided into extrusion grade 14 universal film (VA= 14), 18 foaming (VA= 18) and injection grade 5 (VA=
5) Food packaging film.
PVC used for injection molding is generally type 5 and type 3.
6. What is the Chinese word for 6.PPU?
Reply: PPU is thermoplastic polyurethane.
7. How can I identify PVC plastics? Can PVC be regenerated and granulated? In what way? What is the current market of recycled PVC (2004- 12-4)?
Reply: 1)PVC Chinese name: PVC.
Identification by combustion method, softening or melting temperature range: 75 ~ 90℃; Combustion conditions: difficult to soften; Burning flame state: yellow on the top and green with smoke on the bottom; After leaving the fire: extinguish after leaving the fire; Smell: pungent sour taste.
Identification solvent treatment, solvent: tetrahydrofuran, cyclohexanone, ketone, dimethylformamide; Non-solvent: methanol, acetone, heptane.
2) it can be regenerated and granulated.
3) 3) The recycling process of PVC mainly includes the following six steps:
(1) Pretreatment of PVC waste; (2) Selective dissolution in mixed solvents; (3) separating insoluble matter; (4) precipitation of regenerated PVC;
(5) drying; (6) Recovery and recycling of solvents
4) The current price is about 8200 yuan/ton (2004- 12-4).
8. What is the purpose of EPDM?
Reply: EPDM has ternary and binary EPDM, general use: fully molded products; Universal rubber hose and heat-resistant rubber hose for automobile; Manufacturing electrical components; Because of its excellent extrusion performance, it can be mixed with high viscosity rubber to improve its extrusion performance.
9. What is the bottle cap made of?
A: Generally it is made of PP (polypropylene).
10, ll0412ll0501ll0503ll0504ll0505 respectively represent which manufacturer and what model?
Reply: LL stands for LLDPE；; ; The last four digits represent the delivery time, the first two digits represent the year and the last two digits represent the month. For example, LL0505 indicates that the transaction type is LLDPE and the delivery month is May 2005. And so on.
1 1 and 5000S are linear plastics?
Reply: 5000S is HDPE, not linear plastic.
12, looking for a high temperature resistant plastic. It's about 200 degrees.
Reply: PTFE can meet the above requirements.
In addition, special engineering plastics with high temperature resistance include fluoroplastics, silicone resins, polyetherimide polyetheretherketone liquid crystal polymers, etc. Modified nylon can withstand high temperature above 250 degrees.
13. Does ABS belong to modified polystyrene?
Reply: ABS is an acrylonitrile-butadiene-styrene polymer, not modified polystyrene, which belongs to PS.
14. What is the difference between high-pressure polyethylene glycol and low-pressure polyethylene glycol?
Reply:
High pressure polyethylene (HPPE) is low density polyethylene (LDPE);
Low pressure polyethylene (LPPE) is high density polyethylene (HDPE).
15, I want to run a recycled plastic granule factory, but I don't know what the woven bag is made of, such as PP and ABS.
Reply:
Generally, PP is used as woven bag; ABS has strong rigidity and is generally used to make shells and parts.
16 and Noryl SE 1 GFN3 are what types of plastic materials, and what are their names respectively?
What plastic material is Lexan 940? What's its name? What is the price?
Reply:
Lexan 940 is a PC produced by American General Electric Plastics Company, and the market price is around 34,000. Noriel SE 1.
GFN3J is also a general company, PPO, with a market price of around 35,000.
17, what is the specific gravity of ABS?
Reply:
The density of ABS is about 0/.05g per cubic centimeter/kloc-0, which is slightly heavier than water and has the characteristics of toughness, hardness and rigidity.
18. What kind of plastic is MSRESIN, its speed, model, name, price and output?
Reply:
MSRESIN is a common transparent plastic material. Generally, it is injection molding and extrusion molding, and the transparency is close to PMMA. Used for optical components/toys/lampshades /OA accessories/food containers/household appliances/building materials, etc. Most of them are imported from Japan and Taiwan Province Province, and the quotation is around 15500- 18300.
19. What is the English code name of waste acrylic? What's the price of waste products now?
Reply:
Acrylic is a special plexiglass.
PMMA, commonly known as plexiglass, also known as acrylic or acrylic, is an important thermoplastic developed earlier in Hong Kong. It has good transparency, chemical stability and weather resistance, easy dyeing, easy processing and beautiful appearance, and is widely used in the construction industry.
The price of transparent acrylic waste is about 1 ten thousand; Because the year is approaching, the acrylic waste market is out of stock.
20. What is the difference between the performance of PS material and ABS material?
Reply:
PS plastic (polystyrene), material properties: excellent electrical insulation (especially high-frequency insulation), colorless and transparent, light transmittance is second only to plexiglass, coloring is water-resistant, chemical stability is good, strength is average, but it is fragile, prone to stress embrittlement, and resistant to organic solvents such as benzene and gasoline. Suitable for making insulating transparent parts, decorative parts, chemical instruments, optical instruments and other parts. Moldability: 65438. It does not need to be fully dried and is not easy to decompose, but it has a large thermal expansion coefficient and is easy to generate internal stress. It has good fluidity and can be molded by screw or plunger injection molding machine. 2. High material temperature, high mold temperature and low injection pressure should be adopted to reduce internal stress and prevent shrinkage deformation. 3. Various gates can be used, and the gates can be arcuately connected with the plastic parts to avoid damaging the plastic parts when the gates are disassembled. The demoulding slope is large and the ejection is uniform. It has excellent physical and mechanical properties, excellent low-temperature impact resistance, excellent electrical properties, wear resistance, dimensional stability, chemical resistance and dyeability. Easy to process and shape. ABS is resistant to water, inorganic salts, alkali and acid, insoluble in most alcohols and hydrocarbon solvents, but soluble in aldehydes, ketones, esters and some chlorinated hydrocarbons. The disadvantages of ABS are flammability, low thermal deformation temperature and poor weather resistance. Combustion characteristics: flammable; Keep burning away from fire; Flame * * *, thick black smoke; Softening and foaming; Acrylonitrile smell. Solubility: Soluble solvent: dichloromethane; Insoluble solvents: alcohols, aliphatic hydrocarbons and water. Applications: automobile industry, mechanical equipment, electronic appliances, etc.
2 1. What PP material is used for the syringe? Can it be recycled? How much is a ton?
Reply:
PP material for syringe is a kind of random PP, which can be recycled. The current price includes tax about 13000.
Discarded syringes are medical waste, so they are very useful to avoid injury.
Some netizens recommended South Korea's RP340R(MI25) or 370 Y (MI18); And it is strongly recommended not to use the returned materials, because it is easy to cause medical accidents.
22. What is the use, price and treatment technology of waste PET?
Reply:
Uses: Recycled pet is mainly used for non-food packaging fibers, sheets, bottles, etc. Its development uses include: building materials, food packaging and containers. Japanese companies use polymer alloy improvement technology to process recycled pet into powder coatings with better performance than new pet materials. Price: No public quotation found.
It's basically a single discussion.
Treatment process: Teijin Company of Japan has developed a method to recover DMT (dimethyl terephthalate) and ethylene glycol (ethylene glycol) from waste polyester bottles. First, the waste PET bottle was broken and cleaned, and then it was dissolved in EG. At the boiling temperature of EG and the pressure of 0. 1MPa, PET depolymerized to produce Shuang Yi hydroxyethyl terephthalate (BHET). After filtration, the filter residue and additives were removed, so that BHET reacted with methanol, and transesterification was carried out at the boiling temperature of methanol and the pressure of 0. 1MPa to generate DMT and EG. After distillation, DMT and ethylene glycol were separated, and then DMT was refined by recrystallization. Ethylene glycol is purified by distillation, and methanol can be recycled. The purity of recovered DMT and EG reaches 99.99%, and the production cost is equivalent to that of ordinary DMT and EG methods. DMT can be converted into pure TPA (terephthalic acid), which can be used to make bottle-grade PET resin. The circulating device can produce about 10% of the raw materials for resin production in our company.
23. How are waste plastics classified?
Reply:
Commonly used waste plastics are generally divided into PE, PP, PVC, PET, EPS, ABS, PA, etc. Among them, PE includes plastic greenhouse materials, industrial packaging films, lactic acid beverage bottles, detergent bottles, etc. PP has woven bags, packing belts, binding ropes and some car bumpers. And PVC has plastic door and window profiles, pipes and so on. Pets have tea beverage bottles such as cola and sprite; EPS is commonly known as foam.
24, the chemical name of waste plastics, and all kinds of waste plastics can be made into particles after what plastic products.
For example, what can I do after the mineral water bottle is made into granules? What is its chemical name?
What can I do after the woven bag is made into particles?
Reply:
Thermoplastic products can be granulated after recycling, which is called recycled plastics, and its name is * * recycled materials.
Theoretically, its use is slightly narrower than that of new materials. Because of the technical level of recycling and the particularity of finished products, such as food packaging and medical care. (In order to avoid harm to human body, generally this kind of products do not need to recycle materials).
The advanced recycling technology and strict recycling system in developed countries make the properties of recycled materials close to new materials, and even new uses can be developed through this property and synthesis. Domestic technology is backward, so far there is no enterprise standard or national standard for recycled plastic particles. Therefore, the quality of plastic recycled materials is uneven, and its use depends on its specific technical indicators.
25. What is the English code name of organic plastic (acrylic)?
A: Acrylic is a special plexiglass, abbreviated as PMMA.
26. What is the scientific name of nylon?
Reply:
Nylon is also called PA or polyamide.
27. What plastic is the infusion tube used in the hospital?
Reply: PVC, PE
28. What is the detailed use of PTFE?
Reply:
Polytetrafluoroethylene (PTFE), commonly known as the king of plastics, is the largest variety of fluoroplastics in terms of production and consumption, accounting for about 70% of the total production of fluoroplastics, and is used in many fields such as chemical industry, machinery, electrical appliances, construction, electronics and automobiles.
29. What is the information about PPR? Aluminum-plastic PPR composite pipe and stainless steel PPR composite pipe.
Reply:
There is no supply recently, so there is no quotation for the time being.
PPR pipe products are suitable for domestic and sanitary drinking water supply and hot water heating systems in industrial and civil buildings. It is an upgraded product to replace copper pipes and galvanized pipes, and can be used in: 1 residential cold and hot water systems, 2 pure water pipelines, 3 industrial water and chemical substances transportation and discharge, 4 hot water circulation systems, 5 compressed air pipelines, 6 food and beverage production and transportation systems, and 7 other industrial and agricultural pipelines.
Steel-plastic composite pipe is an ideal environmental protection pipe, which is widely used in urban water supply, natural gas, petrochemical and other fields. Steel-plastic composite pipe has both advantages of metal and plastic; High temperature resistance, high pressure resistance and corrosion resistance; The inner wall of the pipeline is smooth, with small resistance, no scaling, no toxicity, no pollution, antistatic, heat insulation and easy cutting and processing.
Application scope of aluminum-plastic composite pipe:
Industry: Shielded conduits of various instruments and meters, insulated conduits, and pipelines for conveying various gas and liquid media.
Construction industry: indoor cold, hot water and gas pipelines, solar water heater cold and hot pipelines, low temperature radiation and heating pipelines.
Agriculture: Irrigation pipes for nurseries, orchards, gardens and other irrigation projects.
Public utilities: hot and cold water pipes in hotels, oxygen pipes in hospitals, food pipes, air conditioning pipes and ship pipes.
30. What is the plastic for the spring?
Reply:
The main requirements for the properties of spring plastics are: 1, large deformation energy v (that is, small spring modulus e), large strength, especially fatigue strength, and easy to process and shape. The deformation energy v of thermosetting fiber reinforced plastics (FRP) is larger than that of ordinary metals and equivalent to that of spring steel; And is an ideal material for manufacturing leaf springs.
3 1，ABS。 The characteristics, main uses and differences of labels of PS.PP.PE and other materials.
Reply:
ABS has good rigidity, high impact strength, heat resistance, low temperature resistance, excellent chemical resistance, mechanical strength and electrical properties, easy processing, good dimensional stability and surface gloss, easy painting and coloring, and can also be used for secondary processing such as metal spraying, electroplating, welding and bonding. Main uses: automobiles, household appliances, electronics/appliances, building materials, ABS alloy/* * * mixture LDPE has excellent electrical insulation (especially high-frequency insulation), colorless and transparent, with light transmittance second only to plexiglass, good coloring water resistance, good chemical stability and average strength, but it is fragile, prone to stress embrittlement, and not resistant to organic solvents such as benzene and gasoline. Suitable for making insulating transparent parts, decorative parts and chemicals. Film is its main processing product, followed by sheets and coatings, hollow containers such as bottles, cans and barrels, and other various injection and blow molding products, insulation and sheathing of pipes, wires and cables. Mainly used in packaging, agriculture and transportation sectors.
Polypropylene is cheap, light in weight, good in processability and widely used. The development of catalysts and new processes further promoted the expansion of application fields. Some people say, "As long as the material of a product is changed into plastic, then this product has the potential to use polypropylene". Main uses: woven bags, waterproof cloth, durable consumer goods: such as cars, home appliances and carpets.
32. What are the commonly used PC products? What plastic are VCD discs and outer packaging boxes made of?
Reply:
Polycarbonate (PC) material has the advantages of light weight, transparency, high strength, good seismic performance and good machinability. In the development process of more than 50 years, its application field has been expanding.
The application of PC products has penetrated into automobile, construction, medicine, clothing and other industries. PC materials are indispensable in some brand-new fields, such as PC car lights, PC car skylights, optical waveguide fibers in car communication systems, transparent ceilings, PC boards, and PC injection tubes. In addition, self-luminous systems at the bottom of swimming pools, solar energy collection systems, high-definition TV screens, chip-marking fibers in textiles, and so on.
Optical disc is the most familiar PC application field, and it is developing towards large capacity. The storage capacity of the new DVD is expected to reach 654.38+000 billion bytes.
33. Computer performance
Reply:
High impact strength, stable size, colorless and transparent, good coloring, good electrical insulation, corrosion resistance and wear resistance, but poor wetting and sliding performance, stress cracking tendency, easy hydrolysis at high temperature and poor compatibility with other resins.
34. What are the largest recycled plastics markets in China at present?
Reply:
Generally, in areas where new materials are actively traded, the trading of recycled materials is also active, such as Yuyao, Guangdong, Shandong and other places.
35. What is the common name of acetal? How is the performance?
Reply:
Acetal is acetal, acetal diethanol; Commonly known as plastic steel (Hong Kong and Taiwan commonly known as plastic steel); Can be used for outdoor products, such as buttons, with high hardness and moisture resistance, and can be used in cold or dry environment.
36./kloc-what are the plastic raw materials that do not deform at 0/80 degrees?
Reply:
Aromatic nylon can withstand high temperatures up to 260℃, and fluoroplastics can withstand these high temperatures.
37. Is PP powder a general material? Injection molding is as universal as wire drawing? Can you replace PP material? What is the market price? Reply:
PP plastics are all general-purpose plastics. As long as the equipment allows, powdery and granular materials can be substituted for each other, and the current market price is around 10200.
38. How to analyze the daily oil prices of Brent, WTI and the Organization of Petroleum Exporting Countries, and how to see whether the future plastic trend is high or low?
Reply:
Affected by the cost-driven principle: crude oil-naphtha-ethylene-polyethylene-plastic products, the price of crude oil is consistent with the general trend of plastics (short-term deviation is also normal), but this influence should have a certain lag effect in theory, which is not as sensitive as the current domestic plastic market. At present, the impact of international oil prices on the domestic plastic market is mainly the influence of mentality and the role of herd mentality.
When the market returns to rationality, the relationship between supply and demand of plastics itself will have a greater impact on the market price.