Supplementary material (ESI) for Chemical Communications
This journal is © The Royal Society of Chemistry 2004
Direct Synthesis and Aqueous Solution Properties of Y-shaped,
Stimulus-responsive Block Copolymer Surfactants
Yuanli Cai, Carine Burguiere and Steven P. Armes*
Department of Chemistry, School of Life Sciences, University of Sussex, Falmer, Brighton, East Sussex,
BN1 9QJ, UK.
E-mail: S.P.Armes@sussex.ac.uk Fax:+44 1273-677196; Tel: +44 1273-678650
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† Electronic Supplementary Information (ESI) available: [details of
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http://www.rsc.org/suppdata/cc/b0/b000000a/
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CHEM. COMMUN., 2002, 1–XX
1
Supplementary material (ESI) for Chemical Communications
This journal is © The Royal Society of Chemistry 2004
Electronic Supplementary Information (ESI)
Synthesis of PEO23-b-DEA10 and PEO23-b-DEA20 Diblock Copolymers
PEO23-based macroinitiator (PEO23-Br) was synthesised by esterification of monohydroxyl-capped PEO23 with 2-bromoisobutyryl
bromide as reported previously (S. Liu, J. V. M. Weaver, Y. Tang, N. C. Billingham, S. P. Armes, K. Tribe, Macromolecules, 2002, 35,
6131). The diblock copolymers were achieved by the ATRP of DEA using PEO23-Br macro-initiator in 50 % methanol at 20 oC at
[DEA]:[PEO23-Br]:[CuBr]:[bpy] relative molar ratios of 10:1:0.3:0.6 for the PEO23-b-DEA10 and 20:1:0.6:1.2 for the PEO23-b-DEA20.
Polymerisations were terminated after 98 % conversion as judged by 1H NMR studies. The reaction solution turned blue on exposure to
air, indicating aerial oxidation of the Cu(I) catalyst. The resulting copolymer was diluted with methanol and passed through a silica
column to remove the spent ATRP catalyst. The polymer solution was dried under vacuum to remove solvent. GPC analyses indicated
that near-monodisperse diblock copolymers were obtained and and 1H NMR studies (CDCl3) enabled the degrees of polymerisation of
the DEA blocks to be calculated by end group analysis (PEO23-b-DEA10: Mn,cal = 3,100, Mn,NMR = 3,650, Mn,GPC = 6,200, Mw/Mn = 1.21;
PEO23-b-DEA20: Mn,cal = 4,900, Mn,NMR = 5,600, Mn,GPC = 8,400, Mw/Mn = 1.23).
Copolymer Characterization
Dynamic light scattering studies were carried out on 0.5 w/v % aqueous solutions at 20 oC at a scattering angle of 90o using a
Brookhaven BI-9000AT instrument equipped with a 125 mW laser operating at  = 532 nm. The intensity-average hydrodynamic
diameter was calculated from the measured diffusion coefficients using the Stokes-Einstein equation. Surface tensiometry
measurements were made using a Kruss K10 instrument equipped with a Pt ring at 20 oC. The surface tension of doubly-distilled, deionised water (71 mN m-1) was checked periodically between measurements. 0.5 w/v % aqueous solutions were used for all
measurements. 1H NMR spectra (16 scans per spectrum) were recorded at 20 oC in D2O using a 300 MHz Bruker Avance spectrometer.
The solution pH was adjusted as required using either DCl or NaOD.
Abbreviations used for Monomers and Polymers
DMA: 2-(dimethylamino)ethyl methacrylate; DEA: 2-(diethylamino)ethyl methacrylate; MEMA: 2-(N-Morpholino)ethyl methacrylate;
HEMA: 2-hydroxyethyl methacrylate; GMA: glycerol monomethacrylate; HEA: 2-hydroxyethyl acrylate; SEMA: 2-succinyloxyethyl
methacrylate; PEO: poly(ethylene oxide); PMMA: poly(methyl methacrylate); PAA: poly(acrylic acid).
1
2
60
Mn = 2,100
Mw/Mn = 1.10
55
surface tension (mN/m)
Mn = 7,200
Mw/Mn = 1.19
50
45
40
JM1000-b-(DEA10)2
PEO23-b-DEA20
PEO23-b-DEA10
35
30
10
11
12
13
14
15
16
17
18
19
20
25
2
Elution time (min)
3
4
5
6
7
8
9
10
11
12
pH
Fig. S1 THF GPC traces: (1) JM1000-Br2 ATRP macroinitiator and
(2) the corresponding Y-shaped JM1000-b-(DMA10)2 block
copolymer.
O
O
5
4
O
3
O
O
2
Br
O
N
n5
1
50
Br
45
20
O
R
O
O
R = H or CH 3
7, 8
18
16
O
5
1
2
4
-CH2OH
JM1000-based
macroinitiator in CDCl3
12
8 7
3
14
JM1000-b-polyHEMA2 in pyridine-d5
35
10
30
loose aggregates
8
Intensity (kcp)
6
40
Dh (nm)
CH 3
6
1
2
R
5
Fig. S2 Surface tension vs. pH curves for 2 g/L aqueous solutions of the
non-linear JM1000-b-(DEA10)2 and the two linear PEO23-b-DEA10 and
PEO23-b-DEA20 copolymers at 20 oC.
6
25
-OOCCH2CH2COOH
4
JM1000-b-polySEMA2 in pyridine-d5
micelles
2
20
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
0
chemical shift (ppm)
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
o
Temperature ( C)
1
Fig. S3 H NMR spectra for the JM1000-Br2 (upper spectrum), the
JM1000-b-(HEMA10)2 Y-shaped copolymer precursor (middle
spectrum) and the final acidic Y-shaped copolymer [JM1000-b(SEMA10)2 (lower spectrum)].
Fig. S4 Variation of hydrodynamic diameter (Dh) and light
scattering intensity as a function of temperature for 5 g/L aqueous
solution of the JM2005-b-(GMA20)2 Y-shaped copolymer
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