Electronic Supporting Information
“Metallophilic crosslinking” to provide fast-curing and
mendable poly(urethane-metallothiolate) elastomers
Alaitz Ruiz de Luzuriaga, Alaitz Rekondo, Roberto Martin, Germán Cabañero, Hans J. Grande
and Ibon Odriozola*
Materials Division, IK4-CIDETEC Research Center, Paseo Miramón 196, 20009 Donostia-San Sebastián, Spain
E-mail: iodriozola@cidetec.es
FTIR characterization
S2
Mechanical characterization
S3
Thermal characterization
S4
UV-Vis absorbance spectrum
S5
1H
S5
NMR characterization
Gelification of different polymers
S6
Oxidation of polymer 4
S6
S1
FTIR characterization
Figure S1. FTIR spectra of reaction of PPG 1 and 2-chloroethyl isocyanate at 80 ºC at t = 0
(black trace) and at the end (red trace) where the complete disappearance of the NCO
stretching band at 2272 cm-1 and the appearance of a new band corresponding to the
carbonyl group of urethane moiety at 1720 cm-1 can be observed.
FTIR characterization of thioacetate-functionalized PPG (3)
1690 cm -1
Absorbance (a.u.)
1720 cm -1
4000
3500
3000
2500
2000
1500
1000
-1
Wavenumber (cm )
Figure S2. FTIR spectra of purified thioacetate functionalized PPG 3 where the thioacetate
carbonyl stretching band at 1690 cm-1 can be observed.
S2
Absorbance (a.u.)
FTIR characterization of thiol-functionalized PPG (4)
4000
1720 cm -1
3500
3000
2500
1500
2000
1000
-1
Wavenumber (cm )
Figure S3. FTIR spectra of purified thiol functionalized PPG 4 where the absence of the
thioacetate carbonyl stretching band at 1690 cm-1 can be confirmed.
Mechanical characterization
Figure S4. Stress vs. strain curves obtained from the as-synthesized elastomer 5 (black
traces) and from a reprocessed sample after hot pressing at 100 ºC and 30 bar for 20
minutes (red traces).
S3
Thermal characterization
Figure S5. TGA curves of 2, 3, 4 and 5.
Figure S6. DSC curves for elastomer 5. A) From 90 to 0 ºC, and B) from 25 to 100 ºC.
S4
UV-Vis absorbance spectrum
Figure S7. UV-Vis absorbance spectrum recorded (A) in THF (B) from a 150 µm film of the
synthesized PU elastomer 5 showing the lack of surface plasmon resonance (SPR),
corresponding to the absence of silver nanoparticles.
1H
NMR characterization
Figure S8. 1H NMR spectra of thiol functionalized polymer 4. The complete
disappearance of the thioacetate signal at 2.3 ppm confirmed the complete deprotection of
the acetyl groups and the signal at 2.63 ppm confirmed the presence of thiol groups in the
polymer. A negligible ammount of disulfide was also obserbed.
S5
Gelification of different polymers
Figure S9. Addition of AgTFA/Et3N to polymers 2 (A), 3 (B) and 4 (C) by addition. Gelation was
only observed in the case of polymer 4.
Oxidation of polymer 4
Figure S10. Oxidation thiol-terminated polymer 4 by I2 (0.5 N in ethanol) addition. No
gelation was observed.
S6