Characteristics of Polybutadiene rubber
Polybutadiene rubber specifications and properties
Polybutadiene rubber is a synthetic rubber manufactured by the polymerization of isoprene, a small cyclic natural hydrocarbon. Polybutadiene rubber is used in a broad range of applications including tires, hoses, conveyor belts, conveyor belting, and many other industrial applications Polybutadiene [butadiene rubber BR] is a synthetic rubber. Polybutadiene rubber is a polymer formed from the polymerization of the monomer 1,3-butadiene. Polybutadiene has a high resistance to wear and is used especially in the manufacture of tires, which consumes about 70% of the production. Another 25% is used as an additive to improve the toughness (impact resistance) of plastics such as polystyrene and acrylonitrile butadiene styrene (ABS). Polybutadiene rubber accounted for about a quarter of total global consumption of synthetic rubbers in 2012 It is also used to manufacture golf balls, various elastic objects and to coat or encapsulate electronic assemblies, offering high electrical resistivity polybutadiene rubber containing a polymer obtained by block or graft polymerization of cis-1,4-polybutadiene with syndiotactic (syn)-1,2-polybutadiene, alone or blended with the other diene rubber, said syn-1,2-polybutadiene being crystallized and in a short fiber-like shape, and a breaking resistance characteristic and reinforcement characteristic being considerably improved by specifying the diameter and length of said short fiber, which is suitable for various parts of tire or industrial materials, and further relates to a composition of said polybutadiene rubber to which a carbon black is added for preferably used as a chafer or tread of tire, and still further relates to said composition to which a carbon black and an antioxidant are added for preferably used as a rubber blend composition for side wall. High-Cis Polybutadiene rubber “PBR 1220” is produced by a technology of solution polymerization based on Ziegler-Natta (Cobalt) catalyst. It has more than 96% of 1,4 Cis content and very low glass transition temperature. Cured “PBR 1220” has excellent properties such as abrasion resistance, tear strength, resilience, weathering resistance and low rolling resistance (good fuel economy) due to its low glass transition temperature (Tg typically <–90˚C).
Polymerization of butadiene
1,3-Butadiene is an organic compound that is a simple conjugated diene hydrocarbon (dienes have two carbon-carbon double bonds). Polybutadiene forms by linking many 1,3-butadiene monomers to make a much longer polymer chain molecule. In terms of the connectivity of the polymer chain, butadiene can polymerize in three different ways, called cis, trans and vinyl. The cis and trans forms arise by connecting the butadiene molecules end-to-end, so-called 1,4-polymerisation. The properties of the resulting isomeric forms of polybutadiene differ. For example, “high cis”-polybutadiene has a high elasticity and is very popular, whereas the so-called “high trans” is a plastic crystal with few useful applications. The vinyl content of polybutadiene is typically no more than a few percent. In addition to these three kinds of connectivity, polybutadienes differ in terms of their branching and molecular weights. The trans double bonds formed during polymerization allow the polymer chain to stay rather straight, allowing sections of polymer chains to align to form microcrystalline regions in the material. The cis double bonds cause a bend in the polymer chain, preventing polymer chains from aligning to form crystalline regions, which results in larger regions of amorphous polymer. It has been found that a substantial percentage of cis double bond configurations in the polymer will result in a material with flexible elastomer (rubber-like) qualities. In free radical polymerization, both cis and trans double bonds will form in percentages that depend on temperature. The catalysts influence the cis vs trans ratio.
Invention of PBR
Polybutadiene was one of the first types of elastomer or synthetic rubber that was invented. Since this polymer is very similar to natural rubber, namely polyisoprene, its use as an elastomer did not require much thought. This rubber is suitable for applications dealing with low temperatures Car tires are often made of polybutadiene copolymers. Belts, hoses, gaskets and other car parts are also made of polybutadiene, because it shows better resistance to low temperatures than other polymers Many polymers become brittle at low temperatures as a result of a phenomenon called glass transition. Hard rubber called poly(styrene-butadiene-styrene), or rubber, is a copolymer containing polybutadiene. Polybutadiene is a diene polymer; In other words, it is a polymer made from a monomer containing two carbon-carbon double bonds, that is, butadiene. This polymer is made through Ziegler-Natta polymerization.
Application for PBR
ATDM 1220 is appropriate for rubber compounds used in the production of tire, floor coverings, footwear, children toys, rubber hose, belts and golf balls. Typical Physical Properties-Raw Materials
Parameters Units Values Test methods | |||
ML1+4@100℃ | MU | 41-49 | ASTM D1646 |
CIS Content | WT% | MIN 96 | INTERNAL METHOD |
Volatile Material | WT% | MAX 0.75 | ASTM D – 1416 |
Ash Content | WT% | MAX 0.3 | ASTM D – 1416 |
Typical Properties- Compounds
Typical Properties | Units Values Test methods | ||
Compound Mooney Viscosity | MU | MAX 77 | ASTM D – 1646 |
Tensile Strength(35 Min) | Kgf/cm3 | MIN 150 | ASTM D412 |
Elongation at Break (35 Min) | % | MIN 440 | ASTM D412 |
300% Modulus at 145 °C | |||
25 Min |
Kgf/cm3 | 68-108 |
ASTM D412 |
35 Min | 74-114 | ||
50 Min | 74-114 | ||
To each shipping lot/delivery a quality certificate including data on properties of the product determined during release
control is issued. Scope of the testing which is covered by the quality certificate is each time agreed upon in the sales contract.
² Compounding formula according ASTM D–3189.
Packaging for PBR
35 ±0.5 KG bales wrapped with polyethylene film.
36 bales per crate (1260±18 KG).
Transportation of polybutadiene rubber (PBR)
ATDM1220 is typically transported in covered road trucks, in covered railway carriages and in standard shipping containers.1220 is not a dangerous material to transport.
Storage of PBR
Product should be stored in sheltered conditions away from direct sunlight away from radiant heating elements and the temperature should not exceed 30°C.