Mooney [MU]
Remark
Buna® CB 21        73 highly linear
Buna® CB 22        63 highly linear
Buna® CB 24        44 linear
Buna® CB 25        44 long chain branched
Buna® CB 29 MES        37 MES-oil extended
Buna® CB 29 TDAE        37 TDAE-oil extended

 

Buna, for more information; http://tsr.arlanxeo.com/products/polybutadiene-rubber-nd-br/