Fig. 7: Two relaxation modes from UPy bond exchange in telechelic PDMS network.

a G’(ω) (open symbol with dotted line), G”(ω) spectra (close symbol with solid line) of the terminal relaxation process in Tele-25/75 sample at different temperatures (different colors) in which high frequency shoulder shows up. The position of \({\tau }_{{fast}}\) and \({\tau }_{{shoulder}}\) on the spectra measured at 273 K are labeled by arrows. b H(τ) spectra of the terminal relaxation process in Tele-25/75 at different temperatures (different colors) in which high frequency shoulder shows up. The position of \({\tau }_{{fast}}\) and \({\tau }_{{shoulder}}\) on the spectra measured at 273 K are labeled by arrows. c Temperature dependance of 2 adjacent relaxation processes (\({\tau }_{{fast}}\): closed symbol; \({\tau }_{{shoulder}}\): open symbol) correlated with UPy bond exchange in telechelic PDMS with different bond ratios (different colors). d Cartoon of the star-like structure formed by imine bond below the percolation threshold.