Butadiene rubber structure
- Mingpai
- 2024-06-07 14:24:09
Butadiene rubber, specifically cis-1,4-polybutadiene rubber (BR), has a linear polymer structure composed primarily of repeating units derived from the 1,3-butadiene monomer (C4H6). In the case of cis-1,4-polybutadiene, the monomers add together predominantly in a head-to-tail manner, with the double bonds adopting a cis configuration. This means that the hydrogen atoms attached to the carbon atoms involved in the double bond are located on the same side of the polymer chain.
The simplified representation of a single repeat unit of cis-1,4-polybutadiene is:
A longer polymer chain would be a repetition of this unit:
where n represents the number of repeat units and can range from hundreds to thousands, depending on the molecular weight of the polymer.
It's important to note that while the majority of the monomers in cis-1,4-polybutadiene link up in the described manner, a small fraction may polymerize in a trans-1,4 or 1,2 configuration, depending on the polymerization conditions and the catalyst used. These different configurations can influence the material's properties, with cis-polybutadiene being known for its high elasticity, low hysteresis, and good low-temperature flexibility.
