Electronic Supplementary Material (ESI) for Polymer Chemistry.
This journal is © The Royal Society of Chemistry 2015
Supporting Information for
Ion Pairing Effects in the Zwitterionic Ring Opening Polymerization of Valerolactone
Young A. Chang, Robert M. Waymouth
Department of Chemistry Stanford University, Stanford, CA 94305 United States
Log Intrinsic Viscosity
-0.2
-0.3
-0.4
-0.5
Linear pVL
Cyclic pVL
1M LiCl pVL
-0.6
-0.7
4.2
4.25
4.3
4.35
4.4
Log Molecular Weight
4.45
4.5
Figure S1. Mark-Houwink Plot of Intrinsic Viscosity (IV) as a function of log Molecular
Weight for: Circles: Linear pVL synthesized using BnOH initiator, Squares: cyclic pVL
synthesized in neat THF, and Crosses: Linear pVL synthesized in 1M LiCl in THF.
 cyclic
 cyclic
 0.67 ,
 0.66
 linear
 LiCl
Figure S2. Plot of observed rate constant: kobs (s-1) versus [LiCl]. [VL]=1.0M, [NHC]=0.01M
1.2
0.1M LiCl
33%
58%
74%
79%
85%
Norm Wt Fr
1
0.8
0.6
0.4
0.2
0
3.5
1.4
4 log MW
4.5
5
0.25M LiCl
1.2
30%
49%
1
Norm Wt Fr
5.5
64%
0.8
71%
79%
0.6
0.4
0.2
0
3.5
Norm Wt Fr
1.4
4 log MW
4.5
5
5.5
0.5M LiCl
1.2
25%
42%
64%
74%
78%
1
0.8
0.6
0.4
0.2
0
3.5
4 Log MW
4.5
5
5.5
Figure S3. SEC characterization showing the molecular weight evolution of pVL samples at
various [LiCl]. Percentage indicates monomer conversion. [VL]=1.0M, [NHC]=0.01M.
2425.251 2725.393
2225.162
1623.846
1824.961
1000
2926.487
2125.108
Molar Mass (M/Z)
Intens. [a.u.]
1200
5000
3226.620
800
4000
3526.769
3826.968
600
3000
2000
400
1000
200
0
0
1750
2000
Intens. [a.u.]
1500
2250
2500
2750
3000
3250
3500
3750
50
m/z
O
2725.393
1200
Degree of Polymerization
20 25 30 35 40 45
O
2726.390
1000
n=26
O
O
800
C135H216O54Na+ MW=2725g/mol
2724.432
2727.383
600
400
200
0
2720
2722
2724
2726
2728
2730
2732
m/z
Figure S4. MALDI-TOF spectrum of cyclic poly(valerolactone) prepared in THF at 25°C at
t=5min, 35% conversion. [VL]0 = 1.0M, [NHC]0 = 0.01M
800
2725.383
1523.916
3025.523
2425.248
1925.099
Molar Mass (m/Z)
Intens. [a.u.]
1723.993
3225.609
3325.681
600
400
4000
3000
2000
1000
200
0
0
1500
1750
2000
2250
2500
2750
3000
3250
3500
(x monomer) + Na
15 Degree
20 of Polymerization
25
30
35
m/z
Figure S5. MALDI-TOF spectrum of cyclic poly(valerolactone) prepared in THF at 25°C at
t=7min, 23% conversion. [VL]0 = 0.5M, [NHC]0 = 0.0025M
40
Intens. [a.u.]
2443.412
4000
Molar Mass (M/Z)
2243.294
2743.606
6000
2843.665
2143.247
3000
2943.733
2043.187
4000
2000
3043.810
2026.195
3143.891
1943.133
1000
3243.949
2000
1842.065
3344.052
1743.005
0
3544.180
0
1750
2000
2250
2500
2750
3000
3250
Intens. [a.u.]
1500
3500
15 Degree
20 of Polymerization
25
30
35
2443.412
O
O
HO
O
C120H194O49
6000
Na+
Na
OH
n=23
MW=2443g/mol
2446.438
4000
2447.409
O
O
NaO
O
HO
2000
40
m/z
O
O
Li
n=23
2448.376
OH
O
Na
OH
n=23
C120H193O49Na2+ MW=2465g/mol
2465.393
2468.376
C120H194O49Li+ MW=2427g/mol
2449.379
2427.423
0
2420
2430
2440
2450
2460
2470
m/z
Figure S6. MALDI-TOF spectrum of linear poly(valerolactone) prepared in 1M LiCl in THF
quenched at t=30s, 16% conversion. [VL]0 = 1.0M, [NHC]0 = 0.01M . M/z ~ 2427 corresponds
to the lithium adduct of linear pVL. M/z ~ 2443 and 2465 correspond to sodium adducts of
linear pVL.
Figure S7. MALDI-TOF spectra of p(VL) prepared in THF at various [LiCl]. Samples were
quenched at t=30s. From top to bottom: [LiCl]=0.1M (85% conversion), 0.25M (39%
conversion), 0.5M (32% conversion). M/z ~ 5347 and 5369 correspond to linear polymer with
H2O endgroup and M/z ~ 5329 correspond to cyclic polymer.