What are the advantages and disadvantages of rubber products?

1. When rubber products are molded, after a large pressure pressing, the cohesive force inherent in the elastomer cannot be eliminated, and when molding out of the mold, it often produces extremely unstable shrinkage (the shrinkage rate of rubber varies depending on the type of rubber), which must be eased and stabilized after a period of time. Therefore, when a rubber product design at the beginning, regardless of the formula or mold, need to be carefully calculated with, if not, it is easy to produce the product size instability, resulting in low quality products.
2. Rubber is a hot-soluble thermosetting elastomer, while plastic is a hot-soluble cold-setting. The temperature range for molding and curing of rubber is quite different due to different types of vulcanization bodies, and can even be affected by climate change, indoor temperature and humidity. Therefore, the production conditions of rubber products need to be moderately adjusted at any time, and if not, the difference in product quality may occur.
3. Rubber products are made from rubber raw materials after the refining machine to make the rubber blend as raw materials, in the rubber refining according to the characteristics of the required rubber products and design the formula, and set the required product hardness. The products are molded by the rubber plate vulcanizing machine. After molding, the product is finally treated with flying edges to make the surface smooth and burr-free.
4. Rubber products aging test belongs to the aging test category, rubber aging refers to rubber and products in the process of processing, storage and use, due to the comprehensive action of internal and external factors caused by the performance structure changes, and then lose the use of value of the phenomenon. Performance for cracking, sticky, hardening, softening, chalking, discoloration, mold, etc.
Natural Rubber NR
（Natural Rubber is a polymer of isoprene, which is made from latex collected from rubber trees. It has good abrasion resistance, high elasticity, tearing strength and elongation. It ages easily in the air, becomes sticky when exposed to heat, swells and dissolves easily in mineral oil or gasoline, and is resistant to alkali but not to strong acids. Advantages: good elasticity, acid and alkali resistance. Disadvantages: not weather resistant, not resistant to oil (can be resistant to vegetable oil) is the raw material for making tape, hose, rubber shoes, and suitable for making shock-absorbing parts, products used in automobile brake fluid, ethanol and other liquids with hydroxide roots.
Styrene butadiene rubber SBR
（Styrene Butadiene Copolymer is a co-polymer of butadiene and styrene. Compared with natural rubber, it has uniform quality, less foreign matter, better abrasion resistance and aging resistance, but weaker mechanical strength. Advantages: low cost non-oil resistant material, good water resistance, good elasticity below 70 hardness, poor compressibility at high hardness, disadvantages: not recommended for use in strong acids, ozone, oils, oil esters and fats and most hydrocarbons. Widely used in tire industry, footwear industry, cloth industry and conveyor belt industry, etc.
Butyl Rubber IIR
(Butyl Rubber) is made of isobutylene and a small amount of isoprene polymerization, because of the steric hindrance of methyl molecule movement than other polymers, so the gas permeability is less, resistance to heat, sunlight, ozone, electrical insulation is good; resistance to polar agents, the general use temperature range is -54-110 ℃. Advantages: impermeable to most general gases, good resistance to sunlight and odors, can be exposed to animal or vegetable oils or vaporizable chemicals. Disadvantages: Not recommended for use with petroleum solvents, kerosene and aromatic hydrogen. Used for inner tubes of automobile tires, leather bags, rubber paste paper, window frame rubber, steam hoses, heat resistant conveyor belts, etc.
Hydrogenated nitrile rubber HNBR
（Hydrogenate Nitrile is a nitrile rubber that has been hydrogenated to remove some of the double chains, and after hydrogenation, its temperature and weather resistance is much higher than that of ordinary nitrile rubber. The general use temperature range is -25~150 ℃. Advantages: better abrasion resistance than nitrile rubber, excellent corrosion resistance, tensile, tear resistance and compression properties
Good resistance to atmospheric conditions such as ozone, generally used in laundry or dishwashing detergents. Disadvantages: not recommended for use in alcohols, esters or aromatic solutions Air conditioning and refrigeration industry, widely used in environmentally friendly refrigerant R134a system seals.
Automotive engine system seals.
Ethylene propylene rubber (EPDM) is made of ethylene and propylene co-polymerization, so heat resistance, aging resistance, ozone resistance, stability are very good, but can not be sulfur added sulfur. In order to solve this problem, a small amount of the third component with double chain is introduced into the main chain of EP and can add sulfur to become EPDM, the general use temperature is -50 ~ 150 ℃. Excellent resistance to polar solvents such as alcohols, ketones, etc. Advantages: good weather resistance and ozone resistance, excellent water resistance and chemical resistance, alcohols and ketones can be used, high temperature vapor resistance, good impermeability to gases. Disadvantages: Not recommended for food applications or exposure to aromatic hydrogen. Seals for high temperature water vapor environments Seals or parts for bathroom equipment. Rubber parts in braking (brake) systems. Seals in radiators (automotive water tanks).
Nitrile rubber NBR
（The higher the acrylonitrile content, the better the resistance to hydrocarbon fuel oil, but the low temperature performance is worse, the general use temperature range is -25~100 ℃. NBR is one of the most commonly used rubbers for oil seals and O-rings Advantages: good resistance to oil, water, solvents and high pressure oil
Good compressibility, abrasion resistance and elongation.
Disadvantages: Not suitable for use in polar solvents such as ketones, ozone, nitrocarbons, MEK and chloroform. Used to make rubber parts, especially seals, for fuel tanks, lube tanks and in fluid media such as petroleum-based hydraulic fluids, gasoline, water, silicone oil, diester-based lubricants, etc. It is the most versatile and lowest cost rubber seal available.
Neoprene CR
(Neoprene, Polychloroprene) is made of chlorobutylene monomer polymerization. The vulcanized rubber has good elasticity and wear resistance, is not afraid of direct sunlight, has particularly good weather resistance, is not afraid of intense twisting, is not afraid of refrigerants, is resistant to dilute acids, silicone ester lubricants, but not phosphate ester hydraulic oil. It is easy to crystallize and harden at low temperature, and its storage stability is poor. The general use temperature range is -50~150 ℃. Advantages: good elasticity and good compression deformation, the formula does not contain sulfur so it is very easy to make. It is resistant to animal and vegetable oils, and will not be affected by neutral chemicals, fats, greases, oils and solvents, and has anti-combustion properties.
Disadvantages: Not recommended for use among strong acids, nitrocarbons, esters, chloroform and ketones chemicals Seals resistant to R12 refrigerant, rubber parts or seals on household appliances. Suitable for use in a variety of direct contact with the atmosphere, sunlight, ozone parts. Suitable for a variety of flame-resistant, chemical-resistant rubber products.
Fluoroelastomer FKM
Advantages and disadvantages of fluorine rubber and its applicable media
Fluorocarbon is an elastic polymer with fluorine atoms attached to the carbon atoms of the main or side chains of the molecule obtained by polymerization or condensation of fluorine-containing monomers. Due to the different fluorine-containing monomers used in manufacturing, fluorocarbon rubber has many varieties, which can be broadly classified into fluorinated olefin copolymers and nitrosoids copolymers. Specifically, according to the chemical composition, it can be divided into fluorinated olefin-containing fluoroelastomer, fluorosilicone rubber, nitroso fluoroelastomer, fluorinated acrylate rubber, fluorinated phosphonitrile rubber, fluorinated ether rubber, etc. Fluorine rubber has the characteristics of high temperature resistance, oil resistance and resistance to erosion of a variety of chemicals, and is an indispensable material for modern aviation, missiles, rockets, space navigation and other cutting-edge science and technology. As the automotive industry’s requirements for reliability and safety continue to rise, the amount of fluorine rubber in automobiles is also growing rapidly.
Temperature range: -45℃～204℃
Advantages: – Excellent chemical stability, resistant to most oils and solvents, especially acids, aliphatic hydrocarbons, aromatic hydrocarbons, animal and vegetable oils – Excellent high temperature resistance – Good aging resistance – Excellent vacuum properties – Excellent mechanical properties – Good electrical properties – Good permeability
Disadvantages:
– Not recommended for ketones, low molecular weight esters and compounds containing nitro – Poor low temperature performance – Poor radiation resistance
Applicable Media.
– Mineral oil, ASTM No. 1 oil IRM902 oil and 903 oil
– Non-combustible HFD hydraulic fluid
– Silicone oil and silicone ester
– Mineral and vegetable oils and fats
– Aliphatic hydrocarbons (butane, propane, natural gas)
– Aromatic hydrocarbons (toluene, xylene)
– Chlorinated hydrocarbons (trichloroethane, carbon tetrachloride)
– Gasoline (including high-alcohol gasoline)
– High vacuum
Not applicable media:
– Glycol-based brake fluid
– Ammonia, amine, alkali
– Superheated water vapor
– Low molecular weight organic acids (formic acid and acetic acid)