Fig. 11(a) shows that the presence of the O–H group
peak at 3380 cm1 is related to the presence of silanol Si–
OH. In addition, two peaks are observed, i.e. at 890 cm1
and 1096 cm1
, which can be related to the Si–O–Si symmetric
stretch, and Si–O–Si asymmetric stretch, respectively.
The spectrum clearly shows the presence of silica in
the NR vulcanisates.