High-vinyl polybutadiene, stress

Figure 1. Stress relaxation curves for three different extension ratios. Uncross-linked high-vinyl polybutadiene with a weight average molecular weight of 2 million and a reference temperature of 283 K. G is the apparent rubber elasticity modulus calculated from classical affine theory. (Solid line is data from Ref. 1).

B 1,481.2 1,4-Polybutadiene (low vinyl) 1,2-Polybutadiene (high vinyl) Polyethylene Polybutylene Improved material stress-strain properties... 

Another aspect that needs stressing is that the differences among high cis polybutadienes cannot be accounted for by their different hysteresis. In fact, even by assuming an influence of the residual vinyl content, if any, its influence on hysteresis should go exactly in the opposite direction. 

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