Question

Styrene-butadiene elastomers $(SBR)$ are the largest-volume synthetic rubber in the world. What is the ratio of butadiene : styrene in $SBR$ ?

• A. $2 :1$
• B. $3 :1$
• C. $1: 3$
• D. $1: 2$

Answer 1

Answer: (B)

$3 :1$

Answer 2

$SBR$ (Buna-$S$ rubber) is obtained by copolymerisation of a mixture of $1,3$-butadiene and styrene in the ratio of $1, 3$-butadiene and styrene in the ratio of $3 : 1$ in presence of sodium