Rubber Material

1. What is rubber material: Rubber is the only material with high elasticity

1. Definition of rubber: American Society for Measurement and Testing (ASTM D1566): Rubber is a material that can quickly recover its deformation under large deformation; rubber can be modified, and the modified rubber cannot be dissolved in organic solvents Medium, but swellable. Essentially refers to the vulcanization (ie cross-linking) of rubber. The vulcanized rubber material has high elasticity and features: 18-29°C, a sample that can be stretched twice in 1 minute, when the external force is removed, it will retract to less than 1.5 times its original length within 1 minute.

2. Rubber and elastomers II. History of development of natural rubber, synthetic rubber and thermoplastic elastomers.

Application of rubber materials: gradually becoming the fourth strategic resource after petroleum, iron ore and non-ferrous metals!

Automobile tires; production line conveyor belts; engine transmission; high-speed rail vibration reduction; manned aerospace and space station seals and other seals; rubber packers to ensure the safe production of oil and gas wells;

Fighter aircraft, tank rubber parts; submarine sound-absorbing tiles; earthquake resistance and disaster mitigation; thermally conductive elastomers, heat dissipation of microelectronic equipment; reliability and safety of high-tech equipment 3. Challenges and possible solutions for the sustainable development of the rubber industry

1. Resource problem: The planting area of natural rubber trees is limited to the Tropic of Cancer, and the output is limited!

Expansion of the planting area of natural rubber through biological and genetic engineering: 1,000 tons of rubber need to plant 3 million trees, 5,500 management and planting personnel, and an investment of 1,300 US dollars/t. 2. Energy-saving problem: internal consumption wastes driving energy, wasting 10% of automobile fuel;

Green tires have low rolling resistance and can save fuel by 2-5%; wear resistance and wet skid resistance remain unchanged. High-performance rubber nanocomposites are the key to the development of fuel-saving and safe tires. Tire rubber materials are multi-layered and multi-scale nanocomposites; the fuel-saving performance, wet skid resistance and wear resistance of tires are all related to the structure and structure of rubber nanocomposites. Performance is closely related

2. Recycling issues: The annual consumption of rubber is more than 7 million tons; chemically cross-linked rubber is difficult to recycle and reuse; "black pollution" invades the land, pollutes the environment, and easily causes fires. Recycling and reuse of rubber materials: prototype use; pyrolysis of fuel; rubber powder; illegal soil refining; reclaimed rubber (the most important method), 71.3%, taking into account the problems of recycling and insufficient resources. Reclaimed rubber: rubber recycling is the use of physics and chemistry Or biological methods, the process of opening the three-dimensional cross-linked network to form a processable quasi-linear reclaimed rubber.

From traditional rubber recycling technology to green, high-efficiency, continuous dynamic desulfurization of recycled waste rubber technology and application of thermoplastic elastomers: low energy consumption, high efficiency, and convenient recycling for molding processing. Fourth, basic rubber knowledge

(1) 1. Classification: Classification by source and use: natural rubber; comprehensive properties

synthetic rubber

² General-purpose synthetic rubber (replacement): synthetic rubber that can partially or completely replace natural rubber. Its performance and use effect are different, but because it is not restricted by geographical conditions, it develops rapidly, and its production and consumption exceed those of natural rubber styrene butadiene rubber. (SBR, the largest production of synthetic rubber, tires), butadiene rubber (BR, the best elasticity, matching), isoprene rubber (IR, synthetic natural rubber, isoprene rubber cis-1,4 structure content (92%) -97%) not as high as natural rubber (>98%), large varieties of special rubbers: butyl rubber (IIR, best airtight; modified, bromobutyl rubber), nitrile rubber (NBR, currently the largest amount Special synthetic rubber, oil resistance is higher than chloroprene, second only to polysulfide, silicon, acrylate), ethylene propylene rubber (EPM, EPDM, heat resistance, aging resistance, water resistance is the best in the synthesis, the lowest density, making cars Window sealing strips, radiator hoses, etc.), neoprene (CR, weather resistance, flame resistance, oil resistance, chemical corrosion resistance, etc., the highest density, flame retardant, oil resistance, adhesives, the best versatility);

Special synthetic rubber, small varieties of special rubber: Synthetic rubber with special properties and special purposes that can be used under harsh conditions, such as high and low temperature resistant silicone rubber (SiR), acrylic rubber (ACM, heat resistant oxygen, ozone, heat resistant oil , Second only to fluorine, poor hydrolysis and cold resistance, automotive seals), fluorine rubber (FKM), chloroether rubber (CO, ECO). .

Classified by chemical structure: Carbon chain rubber: unsaturated non-polar (natural rubber (NR), styrene butadiene rubber (SBR), butadiene rubber (BR), isoprene rubber (IR)); unsaturated polar (nitrile butadiene rubber) Rubber (NBR), chloroprene rubber (CR)); saturated non-polar (ethylene propylene rubber (EPM), butyl rubber (IIR)); saturated polar (hydrogenated nitrile rubber (HNBR)) heterochain rubber: silicon Rubber (SiR); polyurethane rubber (PU); chloroether rubber (CO, ECO) according to the cross-linking method: chemically cross-linked traditional rubber; thermoplastic elastomer-the third-generation rubber according to the raw material form:

Bulk solid rubber; powder rubber; liquid rubber according to the consumption ratio: NR is the largest, accounting for 40% of all rubber consumption; followed by SBR, accounting for 40%-50% of synthetic rubber consumption; specialty rubber accounting for about 1%. As the performance requirements of rubber products increase, the amount of special rubber will be higher and higher.