Supporting Information
Synthesis of Water-Soluble Zwitterionic Polysiloxanes
Homopolymerization of D3 and D3v. The room temperature, nBuLi-initiated anionic
ROP of D3 and D3v in THF were monitored by GPC. Aliquots (0.1 ml) of each
homopolymerization solution were removed at various time points using dry needles and
syringes, and chlorotrimethylsilane (0.1 ml) was added to the aliquots to quench
propagating polymers. THF and excess chlorotrimethylsilane were removed by rotary
evaporation, and the remaining residue was dissolved in THF (2 ml) and analyzed by
GPC, eluting in THF and calibrated against polystyrene standards.
NMR Spectroscopy of Zwitterionic Siloxane Polymers. NMR spectra of 1PC-3PC and
4PC were obtained in CDCl3:MeOD-d4 mixtures and MeOD-d4, respectively. NMR
spectra of 1SB-3SB and 4SB were obtained in CDCl3:TFE-d3 mixtures and TFE-d3,
respectively.
Chemical shifts in 1H-NMR spectra of 1PC-3PC and 1SB-3SB were
referenced to the residual CHCl3 signal (=7.26 ppm).
29
Si-NMR spectra were conducted
using samples containing chromium(III) acetylacetonate as a T1 relaxation agent to
improve signal-to-noise ratio.
S1
60
20 min
40 min
50
60 min
90 min
RI Signal
120 min
40
152 min
200 min
240 min
30
20
10
21
22
23
24
25
26
1.5
1.45
1.4
1.35
1.3
1.25
1.2
1.15
1.1
1.05
1
8000
Mn (g/mol)
7000
6000
5000
4000
3000
2000
1000
0
0
50
100
150
200
250
PDI
Elution Time (min)
300
Reaction Time (min)
Figure S1. GPC analysis of the anionic ROP of D3 in THF. Top: chromatograms of
reaction solution aliquots at different reaction times; Bottom: estimated number-average
molecular weight and PDI values of the D3 polymerization solution as a function of
reaction time.
S2
210
190
2 min
170
5 min
8 min
RI Signal
150
10 min
130
15 min
110
20 min
90
70
50
30
10
21
22
23
24
25
26
4500
1.5
4000
1.45
3500
1.4
1.35
3000
1.3
2500
1.25
2000
PDI
Mn (g/mol)
Elution Time (min)
1.2
1500
1.15
1000
1.1
500
1.05
0
1
0
5
10
15
20
25
Reaction Time (min)
Figure S2. GPC analysis of the room temperature anionic ROP of D3 v in THF. Left:
chromatograms of reaction solution aliquots obtained at various reaction times; (right)
Change in estimated number-average molecular weight and PDI of the D3v
polymerization solution as a function of reaction time.
S3
a
HS
O
h
d
S
j
k
O P O
O
c
O
NMe3
i
H2O
b
O
g
f
MeOH
e
g,i
h
k
e
a,c,d,f
j
b
MeOH
e
a
c
HS
S
O
f
O
h
g O
d
i
j
O
l
NMe3
f
h,i
j
b
O P O
O
a
e
a
O
O
d c
b
k
g
O
HS
k
O P O
l
a
NMe3
S
Figure S3. NMR spectra of PC-thiol in MeOD-d4: (top) 1H-NMR; (middle)
(bottom) 31P-NMR.
13
C-NMR;
Figure S4. NMR spectra of SB-thiol in MeOD-d4: (top) 1H-NMR; (bottom) 13C-NMR.
S4
a
nBu Si O
42
b
Si O SiMe3
a
42
b
S
S
O
O
nBu Si O
42
O
O P O
O
NMe3
Si O SiMe3
42
S
a
S
O
O
a O
O P O
O
NMe3
Figure S5. Typical NMR spectra of PC-containing polysiloxanes: (top)
(bottom) 31P-NMR.
a
nBu Si O
42
29
Si-NMR;
a
b
Si O SiMe3
42
S
S
b
O
N
SO3
O
Figure S6. Typical 29Si-NMR spectrum of SB-containing polysiloxanes.
S5
160
140
1PC
2PC
3PC
4PC
RI Signal
120
100
80
60
40
20
22
24
26
28
30
32
34
36
38
Elution Time (min)
Figure S7. TFE GPC chromatograms of 1PC-4PC. Single unimodal peaks were
observed for 1PC-3PC. In the 4PC chromatogram, a polymer peak (28.3 minutes) and
an aggregate peak were observed (23.9 minutes). Eluent and flow marker peaks were
observed at 34.4-35.2 minutes and 36.8 minutes, respectively.
200
180
1SB
2SB
160
3SB
4SB
RI Signal
140
120
100
80
60
40
20
22
24
26
28
30
32
34
36
38
Elution Time (min)
Figure S8. TFE GPC chromatograms of 1SB-4SB. Single unimodal peaks were
observed for 1SB-3SB. In the 4SB chromatogram, polymer (28.5 minutes) and aggregate
(23.9 minutes) fractions were observed. Peaks at 34.4-35.2 minutes and 36.8 minutes
correspond to the eluent and the flow marker, respectively.
S6
1SB
1
1PC
Normalized Intensity
2PC
3PC
0.8
4PC
0.6
0.4
0.2
0
1
10
100
1000
Size (nm)
Figure S9. Normalized DLS curves for aqueous solutions ([polymer]=1 mg/ml) for 1SB
and 1PC-4PC.
1
4PC
4SB
Normalized Intensity
0.8
0.6
0.4
0.2
0
1
10
100
Size (nm)
Figure S10. Normalized DLS curves for 1 mg/ml solutions of 4PC and 4SB in TFE
(hydrodynamic sizes of approximately 24 nm).
S7