Styrene Butadiene Rubber (SBR 1507) (23.3% of styrene; Mooney viscosity = 39) was kindly supplied by PETROFLEX S.A, Rio de Janeiro, Brazil.
Styrene Butadiene Rubber residue (SBR-r) (23.3% of styrene) was kindly supplied by CIAFLEX BORRACHAS LTDA, Rio Grande do Sul, Brazil.