Rubber products refer to the activities of producing various rubber products with natural and synthetic rubber as raw materials, also including the use of waste rubber reproduction of rubber products.

A. Types and characteristics of rubber

(i) general-purpose rubber

⒈ natural rubber NR: made from the latex of the three-leaf rubber tree, the basic chemical composition of cis-polyisoprene, a polymer of isoprene.

It is the raw material for making tapes, hoses and shoes, and is suitable for making shock-absorbing parts, products used in automobile brake fluid, ethanol and other liquids with hydroxide roots.

Advantages: good abrasion resistance, high elasticity, tearing strength and elongation, acid and alkali resistance, good overall performance.

Disadvantages: not heat resistant, not oil resistant (vegetable oil resistant), easy to swell and dissolve in mineral oil or gasoline, alkali resistant but not strong acid resistant. Easy to age in the air, and become sticky when exposed to heat.

PEEK Isoprene Rubber IR: full name cis-1,4-polyisoprene rubber, high cis synthetic rubber made from isoprene, produced by solution polymerization method. Because of its structure and performance and natural rubber is similar, so also known as synthetic natural rubber.

It can replace natural rubber in the manufacture of heavy-duty and off-road tires, and can also be used to produce a variety of rubber products.

Advantages: Like natural rubber, it has good elasticity and wear resistance, excellent heat resistance and chemical stability, and better quality uniformity and processing performance than natural rubber.

Disadvantages: the strength of raw rubber (before processing) is significantly lower than that of natural rubber.

Butadiene rubber SBR: made by copolymerization of butadiene and styrene. Is the largest production of general-purpose synthetic rubber, according to the production method is divided into emulsion polymerization of styrene butadiene rubber, solution polymerization of styrene butadiene rubber and thermoplastic rubber (SBR).

It is widely used in the tire industry, footwear industry, cloth industry and conveyor belt industry, etc.

Advantages: Low cost non-oil resistant material, good water resistance, good elasticity below 70 hardness, poor compressibility at high hardness. Compared with natural rubber, it has uniform quality, less foreign matter, better wear resistance and aging resistance, good overall performance and chemical stability, and can be used in combination with natural rubber.

Disadvantages: Weak mechanical strength, not recommended for use in strong acids, ozone, oils, esters, fats and most hydrocarbons.

Singed cis-butadiene rubber BR: The full name is cis-1,4-polybutadiene rubber, which is produced by solution polymerization of butadiene.

Most of it is used in the production of tires, with a small portion used for cold-resistant products, cushioning materials, tapes, shoes, etc.

Advantages: after vulcanization, butadiene rubber has particularly excellent cold resistance, wear resistance and elasticity, less heat generation under dynamic load, good aging resistance, easy to use with natural rubber, neoprene, nitrile rubber, etc.

Disadvantages: poor tear resistance and bad wet-slip resistance.

Be careful with chloroprene rubber CR: made of chloroprene as the main raw material, through homopolymerization or a small amount of other monomers copolymerization. The vulcanized rubber has good elasticity and wear resistance, and the formula does not contain sulfur, so it is very easy to make. It has particularly good weather resistance, is not afraid of intense twisting, is not afraid of refrigerants, is resistant to dilute acids and silicone ester-based lubricants, and generally has a use temperature range of -50-150 ℃.

Neoprene is widely used, such as the production of transport belts and transmission belts, wire and cable covering materials, the manufacture of oil-resistant hose, gaskets and chemical corrosion-resistant equipment lining. Make a variety of direct contact with the atmosphere, sunlight, ozone parts. Suitable for a variety of flame-resistant, chemically resistant rubber products. Not recommended for use among strong acids, nitrocarbons, esters, chloroform and ketones, seals resistant to R12 refrigerant, rubber parts or seals on household appliances.

Advantages: Good overall performance, such as high tensile strength, water, oil, flame, heat, light, aging, oxidation and ozone resistance. Good elasticity and compression deformation, resistance to animal and vegetable oils, will not be affected by neutral chemicals, fats, grease, oils, solvents, with anti-combustion properties. High chemical stability.

Disadvantages: density is large, easy to crystallize and harden at room temperature, bad storage, electrical insulation performance, poor cold resistance, easy to crystallize and harden at low temperature, raw rubber is not stable in storage. Not resistant to phosphate ester hydraulic oil. The expansion in mineral oil with low aniline point is large.

EPDM: Synthesized with ethylene and propylene as main raw materials, good chemical stability, wear resistance, elasticity, oil resistance and styrene-butadiene rubber close. In the EP main chain into a small number of double chain of the third component and can be added sulfur into EPDM, the general use temperature of minus 50-150 ℃. Excellent resistance to polar solvents such as alcohols, ketones, etc. The use is very wide, can be used as tire sidewall, rubber strip and inner tube and automobile parts, for wire, cable cover and high pressure, ultra-high pressure insulation materials. It can be used as light-colored products such as rubber shoes and sanitary products. Can be filled with oil in large quantities and filled with carbon black, products are less expensive, often used as high temperature water steam environment, bathroom equipment seals or parts. Rubber parts in the braking (brake) system. Seals in radiators (automotive water tanks).

Advantages: good resistance to weathering and ozone, excellent resistance to water and chemicals, alcohols and ketones can be used, high temperature vapor resistance, good impermeability to gases. Heat resistance, aging resistance, ozone resistance, electrical insulation stability are excellent.

Disadvantages: Not recommended for food use or exposure to aromatic hydrocarbons.

Borrowing Butyl Rubber IIR: Isobutylene is polymerized with a small amount of isoprene, which has fewer molecular movements than other polymers due to the steric barrier of methyl groups.

It is commonly used in the inner tube of automobile tires, leather bags, rubber paste paper, window frame rubber, steam hose, heat-resistant conveyor belt, etc.

Advantages: impermeable to most gases, resistant to heat, sunlight, ozone, good electrical insulation; resistant to polar solvents, can be exposed to animal or vegetable oils or vaporizable chemicals.

Disadvantages:Not recommended for use with petroleum solvents, kerosene and aromatics.

(ii) Special type rubber

Special type of rubber refers to the rubber with some special properties.

⒈ nitrile rubber NBR: from butadiene and acrylonitrile polymer copolymerization by emulsion, the higher the acrylonitrile content, the better the oil resistance, but the corresponding decline in cold resistance. The general use temperature range is -25-100 ℃. NBR is known for its excellent oil resistance. It can be used in the air at 120 ℃ or in the oil at 150 ℃ for a long time. The electrical conductivity is relatively good.

Widely used, mainly for oil-resistant products, a variety of oil-resistant gaskets, gaskets, sleeves, soft packaging, soft rubber hose, printing and dyeing rollers, cable rubber materials, anti-static rubber products. In the automotive, aviation, petroleum, copying and other industries to become essential elastic materials. Various sealing products, flame retardant products, and phenolic used as structural adhesives.

Advantages: good resistance to oil, water, solvent and high pressure oil. Good compressibility, elongation, abrasion resistance, aging resistance and air tightness and excellent bonding properties.

Disadvantages:Not suitable for use in polar solvents, such as ketones, ozone, nitrocarbons, MEK can be blended with natural rubber. Ozone resistance, electrical insulation and cold resistance are poor.

PEEK Hydrogenated Nitrile Rubber HNBR: Nitrile rubber is made by removing part of the double chain after hydrogenation, and its temperature resistance and weather resistance are much higher than general NBR, and its oil resistance is similar to general NBR. The general use temperature range is -25-150 ℃.

It is suitable for use in laundry or dishwashing detergents, and is widely used in environmental protection refrigerants, seals in R134a systems, and seals in automobile engine systems.

Advantages: good anti-wear properties, excellent corrosion, tension, tear and compression resistance. Good resistance to atmospheric conditions such as ozone.

Disadvantages: Not recommended for use in alcohols, esters or aromatic solutions.

Silicone Rubber Q: The main chain consists of alternating silicon and oxygen atoms to form the main chain, and the side chain is a carbon group with organic groups on the silicon atoms. The largest use is the side chain for ethylene silicone rubber. Both heat and cold resistant, the use temperature is between 100-300 ℃, it has excellent weather resistance and ozone resistance and good insulation.

Silicone rubber products are biocompatible materials and are closely related to people's lives. Remote controls, keyboards, pos machines, scanners, cell phones, electronic dictionaries, cell phone covers, etc. are all related to silicone rubber. Mainly used in aviation industry, electrical industry, food industry and medical industry, etc. Colorless silicone rubber products are non-toxic and can be used as artificial organs, used in beauty industry and physical therapy industry, etc.

Advantages: high and low temperature resistance, ozone resistance, good electrical insulation.

Disadvantages: low strength, poor tear resistance, and poor abrasion resistance.

Singing Fluoroelastomer FKM: Fluoroelastomers are synthetic polymer elastomers made by polymerizing or condensing fluorine-containing monomers with fluorine atoms attached to the carbon atoms of the main or side chains of the molecule. There are many varieties of fluoroelastomers, depending on the fluorine-containing monomer used, and they can be broadly classified into fluorinated olefin copolymers and nitroso copolymers. It is usually expressed by the number of fluorine atoms in the fluorine containing units in the copolymer, such as fluoroelastomer 23, which is a copolymer of vinylidene fluoride and trifluorochloroethylene. According to the chemical composition can be divided into fluorine-containing alkene class fluorine rubber, fluorosilicone rubber, nitroso fluorine rubber, fluorinated acrylate rubber, fluorinated phosphonitrile rubber, perfluorinated ether rubber, etc..

It is widely used in modern aerospace, aviation, automobile, petroleum and household appliances, and is a key material that cannot be replaced in the national defense cutting-edge industry.

Advantages: high temperature resistance, oil resistance, corrosion resistance, oxidation resistance, solvent resistance, flame resistance, chemical resistance and weather resistance.

Be careful with polysulfide rubber PSR: made by polysulfide condensation of dihaloalkane and alkali metal or alkaline earth metal. In addition, there are polyurethane rubber, chlorohydrin rubber, acrylate rubber, etc., mostly used with nitrile rubber.

Advantages: excellent resistance to oil and solvents.

Disadvantages: strength is not high, aging resistance, processing is not good, there is an odor.

Select sponge rubber, also known as foam rubber, foam rubber or microporous rubber, is a porous elastic material, which is a general term for a variety of rubber with a pore-eye structure. This type of porous materials of the eye throughout the material as a whole, according to the different eye structure, divided into closed hole (eye and eye are not connected to each other), open hole (eye and eye are not completely separated from each other by the hole wall, with a certain degree of connectivity) and mixed hole (both open hole and closed hole two kinds of structure) three.

Microporous rubber mainly includes two types of expanded rubber and sponge rubber. Including soft sponge, hard sponge, micro bubble sponge, conductive sponge, magnetic sponge, water expansion sponge, composite sponge, etc..

Sponge rubber products are widely used in sealing, shock absorption, heat insulation, sound insulation, printing and dyeing and even ion exchange and many other aspects, in aviation, automotive, instruments, meters, home appliances and packaging industry have a wide range of applications. Its shape has plate, strip, tube, roller, gasket, etc., with a wide range of specifications and different shapes. Different conditions of use require different eyelet structures and aperture sizes. For this reason, the requirements in the formulation and processing technology to make corresponding adjustments to achieve the corresponding use of performance.

Second, the use of rubber

⒈ Transportation

The rubber industry is developed with the automotive industry. Rubber consumption in transportation occupies a significant proportion. In sea, land and air transportation, which is inseparable from rubber products. For example: a liberation 4 tons of heavy vehicles, need rubber products more than 200 kg, a hard-seat carriage needs to be assembled rubber products total weight of more than 300 kg, a huge ship of 10,000 tons need rubber products nearly 10 tons heavy, a jet airliner needs nearly 600 kg of rubber. As a means of transport tires, rubber spring shock absorbing products for railroad vehicles and cars, large stores, stations, subways, people carrying transport belts. In addition, there are "hovercraft" and "hovercar" made of rubber.

Peal industrial mine

The industrial sector needs a large number of large and small rubber products, many varieties, a wide range of uses, some have special requirements. The main products are tapes, hoses, sealing gaskets, rubber rollers, rubber sheets, rubber linings and labor protection products. In mining, coal, metallurgy and other industrial applications tape, wire rope core transport belt or synthetic fiber transport belt to transport finished products. Mining mill rubber lining, forged rubber instead of manganese steel, the service life increased by two to four times, but also reduce the noise, this product has been promoted in the world.

Χ Agriculture, forestry and water conservancy

In addition to tractors and agricultural machinery with a variety of tires, combine harvesters need to use rubber tracks, irrigation with pools, reservoirs using rubber impermeable layer and rubber dams, rubber boats, life-saving supplies, etc. The amount is growing in agricultural by-products processing equipment and forestry, animal husbandry, fisheries technology and equipment, etc., have rubber accessories. Such as an iron cow - 40 type wheeled tractor, the need for rubber products as many as 121 pieces. With the great development of agricultural mechanization and farmland water conservancy, more and more rubber products will be needed.

Singed Military Defense

Rubber is an important strategic material, and it is widely used in military defense. For example, a tank uses more than 800 kilograms of rubber; a 30,000-ton warship uses 68 tons of rubber, and there are many different kinds of ships, tents, warehouses, protective gear, and bathing suits made of rubber. As for the national defense cutting-edge technology needs high temperature resistance, low temperature resistance, oil resistance, high vacuum resistance and other special properties of rubber products is indispensable. With the development of national defense modernization, the requirement to be able to resist the temperature range of minus 100-400 ℃, and can resist a variety of acids, alkalis and oxidants with special properties of rubber, is being developed and produced.

Be careful with civil engineering construction

The machinery used in construction, transportation equipment, protective supplies, etc. have rubber products accessories. For example, the glass window sealing rubber strips used in buildings, soundproof flooring, anechoic sponges, rubber carpets, rainproof materials and with emulsion coatings. Large rubber spring seat cushions are installed to reduce the vibration and noise caused by the subway and to mitigate the damage to buildings by earthquakes. Mixing latex into cement can improve the elasticity and abrasion resistance of cement. Adding 3% of rubber or latex to asphalt to pave road surfaces prevents cracking and improves impact resistance.

Select electrical communication

Another characteristic of rubber is that it has good insulating properties and is not easy to conduct electricity. Various wires and cables are mostly made of rubber. Hard rubber is also used to make hoses, sticks, sheets, partitions and battery cases. In addition, it is also widely used as protective supplies insulating gloves, insulating rubber boots and shoes, etc.

Borrowing Medical and health care

There are many rubber products in the medical and health sector, such as various hoses in hospitals, surgical gloves, ice capsules, sponge seat cushions, etc. are mostly rubber products. As accessories of medical equipment and instruments also have rubber products. Medical rubber products often also have special requirements, such as non-toxic, sterilization, physiological inertia, radiation resistance, etc.. Butyl rubber has high biological inertia, chemical stability and more micro-permeability and permeability, used to process rubber bottle stopper, can ensure the preservation of highly hygroscopic, antibiotic and anti-cancer agents. The use of silicone rubber manufacturing artificial organs and human tissue substitutes have made great progress, but also use it to make drug capsules, into the body at the appropriate location, so that the capsule drug slowly and continuously released, both to improve the efficacy and relatively safe.

Storage

Rubber films are widely used for regulated storage of fruits and vegetables. Silicone rubber has superior permeability to CO2 and O2 and proper permeability ratio. According to the differences in the respiration intensity and quantity of different fruits and vegetables, silicone rubber air bags of various sizes are made to maintain the right amount of CO2 inside the bags to form a good gas storage environment, thus inhibiting the respiration intensity of fruits and vegetables, slowing down the metabolic rate and postponing the release of fruits and vegetables.