A maximum in the loss modulus E
00 is observed for the composites as shown in
Fig. 16.
At filler loading higher than 10 phr, a pronounced maximum is observed. It is
thus very appealing to make the hypothesis that different contributions are at stake
0.01
0.8
1.2
1.6
2.0
2.4
E' (EPa)
2.8
0.4
1
10
100
% Strain
0.1
Fig. 15 Strain dependence of the storage modulus for NR filled with nanosilica: (open circle)
0 phr, (open triangle) 5 phr, (inverted triangle) 10 phr, (open diamond) 15 phr, (asterisk) 20 phr;
the dotted lines represent the curve firs according to the model
1E-3
0.03
E¨ (MPa)
0.18
0.15
0.12
0.09
0.06
% Strain
100
10
1
0.1
0.01
Fig. 16 Strain dependence of loss modulus for silica-filled NR: (open diamond) 0 phr, ( filled
circle) 5 phr, ( filled triangle) 15 phr, (asterisk) 20 phr
Modeling of Non-Linear Viscoelastic Behavior of Filled Rubbers
211