Figure 4: Shear rheology on reinforced elastomers.

Comparison of storage (G’) and loss moduli (G’’) at 1 rad s⁻¹ (a) of unmodified PIB as a function of molecular weight, (b) of M0–M5 and D0–D2 as a function of hydrogen-bonding sites per end group and (c) of different blends of M2/D2 as a function of composition; the blends exhibited superior shear moduli compared with those of high molecular weight PIB even for low fractions of D2. (d) Whereas the parent PIB amine was a viscous liquid, M2 was a sticky solid, D2 a brittle powder and a blend of 10 wt% of D2 in M2 was an ‘inherently reinforced’ thermoplastic elastomer (Fig. 1c). See Supplementary Figs 7–10 for more details on rheology measurements and temperature-dependent infrared spectroscopy.