Specimen preparation
Specimens were blended with a mechanical blending method.
Mastication was conducted with the FKM and HNBR raw materials
at 60 8C for 5 min, respectively using an open roll mill (8 in. open
roll mill, Hyun Jin). Separately masticated FKM raw material and
HNBR material were blended at 60 8C for 5 min, the additives were
supplied, and the compound was masticated at 60 8C for 15 min to
produce a sheet. A plain specimen (dumbbell type No. 3) and a
compressed specimen were prepared at regular temperature
(160 8C) and pressure (140 kg/cm2) to measure the properties of
the blended final master batch.