Supporting Information
Copolymerization of a Dendronized Monomer with Styrene and
Different Acrylates: Determination of Reactivity Ratios
Anke Krebs, Anna Müller-Cristadoro, Rabie Al-Hellani, Bernd Bruchmann and A. Dieter
Schlüter
Contents
Reactivity Ratios ....................................................................................................................................... 5
MG1 and Styrene................................................................................................................................... 7
MG1 and tert-Butyl acrylate ............................................................................................................... 11
MG1 and tert-Butyl methacrylate ....................................................................................................... 14
MG1 and Methyl methacrylate ............................................................................................................ 17
MEO2MA and Styrene ........................................................................................................................ 20
MG1.5 and Styrene.............................................................................................................................. 23
MG2 and Styrene................................................................................................................................. 25
NMR-Spectra........................................................................................................................................... 29
1
Experimental Procedure
Monomer synthesis:
Scheme 1: Synthesis of first-generation monomer MG1.
Epichlorohydrine (1 eq) and 2-methoxyethanol (3 eq) were heated to 50 °C and an aqueous
solution of NaOH (19 mol/l; 3 eq) was added. The reaction mixture was stirred overnight before
it was extracted with dichloromethane (3x). The combined organic phases were dried over
MgSO4 and the solvent was evaporated to yield the desired alcohol which was used without
further purification.
The alcohol (1 eq), triethylamine (3 eq) and DMAP (0.1 eq) were dissolved in dichloromethane.
The reaction vessel was immersed in an ice-bath and methacryloyl chloride (2 eq) was slowly
added. The reaction was stirred overnight at room temperature. The reaction solution was washed
with water, aqueous NaOH (10%), 0.1M HCl and again with water. The organic phase was dried
over MgSO4 and the solvent was evaporated. Column chromatography using hexane /
ethylacetate (2:1) as eluent yielded the desired product.
H-NMR (300 MHz, CDCl3):  = 1.94 (s, 3H, CH3); 3.37 (s, 6H, OCH3); 3.50-3.70 (m, 12H,
CH2); 5.19-5.23 (m, 1H, CH); 5.57 (s, 1H, CH); 6.13 (s, 1H, CH) ppm. 13C-NMR (75 MHz,
CDCl3):  = 18.5; 59.2; 70.0; 70.9; 72.0; 125.9; 136.4; 167.0 ppm. H-MS (m/z) (C13H24O6Na):
calcd.: 299.1465, found: 299.1465.
1
Monomer Synthesis MG1.5 and MG2: Following the above mentioned procedure, 2methoxyethanol (1 eq) was dissolved in aqueous NaOH (19 mol/l; 3 eq) and heated to 55 °C.
Epichlorohydrine (1 eq) was slowly added, followed by the successive addition of 0.5 eq, 0.25
eq, 0.125 eq, 0.06 eq and 0.03 eq of epichlorohydrine every two hours. After the last of the
epoxide was added, the reaction was stirred at 55 °C overnight. The mixture was extracted with
dichloromethane repeatedly and the organic phase dried over MgSO4. Evaporation of the solvent
2
yielded the crude alcohol which was dissolved in dichloromethane, along with triethylamine (3
eq) and DMAP (0.5 eq). The reaction was cooled in an ice bath and methacryloyl chloride (2.4
eq) was slowly added. The mixture was allowed to warm to room temperature and stirred
overnight before it was washed with water, NaOH (10%), 0.1M HCl and again water. The
organic phase was dried over MgSO4 and the solvent was evaporated. Column chromatography
of the crude mixture using first ethyl acetate and then a mixture of ethyl acetate and acetone
(15:1) as eluent yielded the desired macromonomers MG1.5 and MG2 as fraction 1 and fraction
2, respectively.
MG1.5: 1H-NMR (300 MHz, CDCl3):  = 1.94 (s, 3H, CH3); 3.36-3.81 (m, 30H, OCH3, CH2,
CH); 5.15-5.17 (m, 1H, CH); 5.56 (s, 1H, CH); 6.12 (s, 1H, CH) ppm. 13C-NMR (75 MHz,
CDCl3):  = 18.5; 59.2; 69.2; 70.1; 70.9; 71.0; 71.6; 71.7; 72.1; 72.2; 72.4; 76.8; 79.1; 125.9;
136.6; 167.0 ppm. H-MS (m/z) (C19H36O9Na): calcd.: 431.2257, found: 431.2246.
MG2: 1H-NMR (300MHz, CDCl3):  = 1.94 (s, 3H, CH3); 3.36-3.81 (m, 42H, OCH3, CH2, CH);
5.16 (m, 1H, CH); 5.56 (s, 1H, CH); 6.11 (s, 1H, CH) ppm. 13C-NMR (75 MHz, CDCl3):  =
18.9; 59.6; 69.5; 69.6; 70.4; 70.9; 71.3; 71.4; 71.5; 71.8; 71.9; 72.0; 72.5; 72.6; 72.9; 73.3; 78.0;
79.2; 79.4; 79.5; 126.2; 137.0; 167.4 ppm. H-MS (m/z) (C25H48O12Na): calcd.: 563.3044, found:
563.3045.
Copolymerization: All reagents were used as a 5 mol/l-solution in toluene, except methyl
methacrylate (10 mol/l) and AIBN (0.08 mol/l). The appropriate amounts of monomer were
placed in a Schlenck-tube and AIBN was added so that the amount of solvent adds up to 0.1 ml.
The solution was dried by several freeze-pump-thaw cycles. The reaction vessel was placed in a
pre-heated oil bath at 65 °C until the desired amount of copolymer was generated. The reaction
mixture was filtered through a plug of silica gel and washed with dichloromethane. The solvent
was evaporated and the obtained polymer was dried in vacuo. The polymer was dissolved in
deuterated chloroform and analyzed by NMR. The experiments were repeated several times and
the results averaged where appropriate. Proof of copolymerization was obtained by DSCmeasurements.
DSC measurements were carried out using a DSC Q1000 V7.3 build 249 machine. Recording of
NMR samples was done on a 300 MHz instrument by Bruker. All signals were referenced to the
CDCl3-solvent peak at 7.26 ppm.
Determination of molar ratios:
The determination of the molar ratios of the two monomers in the copolymer will be explained
with the help of two exemplary NMR-spectra. If individual signals for both monomers could be
detected, their ratio was determined via the direct comparison of the appropriately calibrated
integrals (Figure 1).
3
Figure 1: NMR-spectra of the copolymerization of MG1 and styrene. Integral I represents the aromatic protons of
styrene, while integral II depicts the side chains of monomer MG1.
If no individual signals for the monomers could be detected the molar ratio was determined by
putting the integral of the gylcerol proton of MG1 in relation to the integral of the polymeric
backbone from which the 5 protons belonging to the MG1 unit have been subtracted (Figure 2).
4
Figure 2: NMR-spectra of the copolymerization of MG1 and MMA. Integral I represents the glycerol proton of
MG1, signal II those of the polymeric backbone. Thus the molar ratio can be calculated as the value of signal II from
which the 5 protons of the MG1 unit have been subtracted, divided by the number of protons belonging to the MMA
backbone.
The values of the reactivity ratios highly depend on which integrals are chosen. It turned out that
the values of the reactivity ratios differed depending on whether the glycerol proton or the side
chains were used for comparison. In cases were the glycerol proton could not be clearly detected,
e.g. in the copolymerization of MG1 with styrene, the more consistent results were derived when
the signal of the side chain was used.
Reactivity Ratios
The methods and equations used to determine the reactivity ratios are shown below and each
procedure is briefly explained. The feeds and molar ratios as well as the graphical plot for each
pair of monomers are given below.
Mayo and Lewis
The data of the feed ([M1] and [M2]) and molar ratios of the monomers in the copolymer (m1 and
m2) are substituted into eq. (1) for each experiment and r2 is plotted as a function of a series of
assumed values of r1, resulting in a straight line for each experiment. The coordinates of the
center of the smallest circle whose periphery either crosses or tangents all lines give the values of
r1 and r2.
r2 
 M1   m2 1   M1  r   1
 
 
 M 2   m1   M 2  1  
(1)
Finemann and Ross
F
   f  1
 f 
(2)
is plotted versus
F2
(3)
f
with F = [M1] / [M2] and f = m1 / m2. The slope of the resulting best fit straight line renders r1.
The reactivity ratio r2 is determined by the slope of the best fit straight line resulting from the plot
of
5
 f  1
(4)
F
versus
f
F2
(5)
Kelen and Tudos
This method is based on eq. (6), which can be solved by plotting  versus . The result is a
straight line which at (0) and (1) gives the values of –r2/ and r1, respectively.
    r1  r2    r2 
(6)
with
G
F
F

F
 M1  m2  m1  1
G
 M 2  m1  m2 

 M   m
F   1  2
  M 2   m1
(7)
(8)
(9)
2
The symmetry factor  is given as   Fmin Fmax
(10)
.
With the help of r1 and r2 it is possible to calculate the probability p11 of forming M1M1 dyads in
the copolymer at a given monomer feed
p11 
r1
r1   M 2   M1 
(11)
Accordingly the probabilities p12, p21 and p22 for forming pairs of M1M2, M2M1 and M2M2,
respectively, are given by
p12 
M 2 
r1  M 1    M 2 
6
(12)
 M1 
r2  M 2    M 1 
r2  M 2 
p22 
r2  M 2    M 1 
p21 
(13)
(14)
In a similar manner the number-average sequence length n can be calculated according to
n1 
n2 
r1  M 1    M 2 
M 2 
(15)
r2  M 2    M 1 
(16)
 M1 
MG1 (M1) and Styrene (M2)
Entry
M1
M2
m1
m2
1
2
3
4
5
9
2
1
1
1
1
1
1
2
9
0.64
0.29
0.167
0.101
0.033
0.2
0.2
0.2
0.2
0.2
7
Conversion
(%)
0.4
6.8
5.0
2.9
2.6
ML
9:1
2:1
1:1
1:2
1:9
20
15
10
5
r1
0
-5
-10
-15
-20
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
0.8
1.0
r2
FR
Determination of r1
7
6
5
(F/f)(f-1)
4
3
2
1
Equation
y = a + b*x
Weight
No Weighting
Residual Sum
of Squares
0.16823
Pearson's r
0.99746
0.99322
Adj. R-Square
Value
0
B
Intercept
B
Slope
Standard Error
-0.46409
0.12429
0.26421
0.0109
-1
0
5
10
15
2
F /f
8
20
25
1.2
Determination of r2
0
(f-1)/F
-2
-4
-6
Equation
y = a + b*x
Weight
No Weighting
0.0317
Residual Sum
of Squares
-0.99964
Pearson's r
0.99904
Adj. R-Square
Value
-8
B
Intercept
B
Slope
-2
0
2
Standard Error
0.3079
0.05498
-0.58644
0.00907
4
6
8
10
12
14
2
f/F
KT
0.3
0.2
0.1

0.0
-0.1
-0.2
-0.3
Equation
y = a + b*x
Weight
No Weighting
Residual Sum
of Squares
0.00967
Pearson's r
0.98219
0.95292
Adj. R-Square
Value
B
Intercept
B
Slope
Standard Error
-0.42075
0.04647
0.7359
0.08129
-0.4
0.0
0.2
0.4
0.6

9
0.8
1.0
10
MG1 (M1) and tert-Butyl acrylate (M2)
Entry
M1
M2
m1
m2
1
2
3
4
5
9
2
1
1
1
1
1
1
2
9
1
1
1
1
1
0.107
0.376
0.690
1.523
6.996
ML
9:1
2:1
1:1
1:2
1:9
6
4
2
0
r2
-2
-4
-6
-8
-10
-12
-14
-0.5
0.0
0.5
1.0
r1
11
1.5
2.0
Conversion
(%)
6.9
7.7
3.4
7.4
8.5
FR
Determination of r1
8
(F/f) (f-1)
6
4
2
Equation
y = a + b*x
Weight
No Weighting
Residual Sum
of Squares
0.16647
Pearson's r
0.99839
0.99571
Adj. R-Square
0
Value
Intercept
Slope
Standard Error
-0.51511
0.12861
0.99255
0.03256
-2
10
8
6
4
2
0
2
F /f
2
Determination of r2
0
(f-1)/F
-2
-4
-6
Equation
y = a + b*x
Weight
No Weighting
0.16
Residual Sum
of Squares
-0.99852
Pearson's r
0.99605
Adj. R-Square
Value
Intercept
Slope
-8
0
2
Standard Error
1.31151
0.13078
-0.77558
0.0244
4
6
8
2
f/F
12
10
12
KT
1.0
0.8
0.6
0.4

0.2
0.0
-0.2
Equation
y = a + b*x
Weight
No Weighting
Residual Sum
of Squares
0.23194
Pearson's r
0.93878
0.84174
Adj. R-Square
-0.4
Value
Intercept
Slope
Standard Error
-0.78518
0.24589
2.08491
0.44176
-0.6
-0.8
0.0
0.2
0.6
0.4

13
0.8
1.0
MG1 (M1) and tert-Butyl methacrylate (M2)
Entry
M1
M2
m1
m2
1
2
3
4
5
9
2
1
1
1
1
1
1
2
9
1
1
1
1
1
0.176
0.792
1.132
2.869
10.679
ML
9:1
2:1
1:1
1:2
1:9
10
r2
0
-10
-0.5
0.0
0.5
r1
14
1.0
1.5
Conversion
(%)
5.3
3.6
8.6
3.3
4.5
FR
Determination of r1
8
(F/f)(f-1)
6
4
2
Equation
y = a + b*x
Weight
No Weighting
1.22991
Residual Sum
of Squares
0.9878
Pearson's r
0.96768
Adj. R-Square
Standard Error
Value
Intercept
0
Slope
-0.90471
0.34521
0.58811
0.05352
-2
8
6
4
2
0
16
14
12
10
2
F /f
Determination of r2
2
0
(f-1)/F
-2
-4
Equation
y = a + b*x
Weight
No Weighting
0.06824
Residual Sum
of Squares
-6
-0.99935
Pearson's r
0.99826
Adj. R-Square
Value
Intercept
Slope
-8
-1
0
1
Standard Error
0.50724
0.08303
-1.14128
0.02385
2
3
4
2
f/F
15
5
6
7
8
KT
0.6
0.4
0.2
0.0

-0.2
-0.4
-0.6
-0.8
Equation
y = a + b*x
Weight
No Weighting
Residual Sum
of Squares
0.01963
Pearson's r
0.99462
0.9857
Adj. R-Square
Value
-1.0
Intercept
Slope
Standard Error
-1.62266
0.08793
2.18138
0.13111
-1.2
-1.4
0.0
0.2
0.6
0.4

16
0.8
1.0
MG1 (M1) and Methyl methacrylate (M2)
Entry
M1
M2
m1
m2
1
2
3
4
5
9
2
1
1
1
1
1
1
2
9
1
1
1
1
1
0.836
1.142
1.601
2.474
16.22
Conversion
(%)
6.6
9.9
6.2
2.9
1.1
ML
9:1
2:1
1:1
1:2
1:9
40
30
20
10
r2
0
-10
-20
-30
-40
-0.6
-0.4
-0.2
0.0
0.2
r1
17
0.4
0.6
0.8
1.0
1.2
FR
Determination of r1
1.5
1.0
0.0
-0.5
-1.0
Equation
y = a + b*x
Weight
No Weighting
Residual Sum
of Squares
0.92554
Pearson's r
0.90929
Adj. R-Square
0.76909
Standard Error
Value
Intercept
-0.8971
0.28533
Slope
0.03557
0.0094
-1.5
-2.0
0
-10
70
60
50
40
30
20
10
2
F /f
Determination of r2
0
-2
(f-1)/F
(F/f)(f-1)
0.5
-4
-6
Equation
y = a + b*x
Weight
No Weighting
1.71347
Residual Sum
of Squares
-0.98331
Pearson's r
0.95587
Adj. R-Square
Value
-8
Intercept
Slope
Standard Error
0.51695
0.43556
-1.71441
0.18313
-10
0
1
2
3
2
f/F
18
4
5
KT
0.1
0.0

-0.1
-0.2
Equation
y = a + b*x
Weight
No Weighting
0.039
Residual Sum
of Squares
-0.3
0.83122
Pearson's r
0.5879
Adj. R-Square
Value
Intercept
Slope
-0.4
Standard Error
-0.31062
0.08125
0.40955
0.15815
-0.5
0.0
0.2
0.4
0.6

19
0.8
1.0
MEO2MA (M1) and Styrene (M2)
Entry
M1
M2
m1
m2
1
2
3
4
9
2
1
1
1
1
1
2
0.871
0.247
0.151
0.082
0.1983
0.2
0.1993
0.1184
ML
9:1
2:1
1:1
1:2
15
10
5
r2
0
-5
-10
-15
-20
-0.5
0.0
0.5
1.0
r1
20
1.5
2.0
Conversion
(%)
2.2
4.0
1.8
2.8
FR
Determination of r1
8
7
6
(F/f)(f-1)
5
4
3
2
1
Equation
y = a + b*x
Weight
No Weighting
Residual Sum
of Squares
0.20416
Pearson's r
0.99724
0.99175
Adj. R-Square
Value
0
Standard Error
B
Intercept
-0.7183
0.20408
B
Slope
0.41335
0.02174
-1
-2
0
2
4
6
8
10
12
14
16
18
20
2
F /f
Determination of r2
0.5
(f-1)/F
0.0
-0.5
Equation
y = a + b*x
Weight
No Weighting
0.08463
Residual Sum
of Squares
-1.0
-0.98038
Pearson's r
0.94172
Adj. R-Square
Value
-1.5
0.0
B
Intercept
B
Slope
0.5
Standard Error
0.46186
0.1391
-0.67741
0.0963
1.0
1.5
2
f/F
21
2.0
2.5
3.0
KT
0.35
0.30
0.25
0.20

0.15
0.10
0.05
0.00
Equation
y = a + b*x
Weight
No Weighting
Residual Sum
of Squares
0.00303
Pearson's r
0.98188
0.94613
Adj. R-Square
Value
-0.05
B
Intercept
B
Slope
Standard Error
-0.16056
0.03625
0.55726
0.07605
-0.10
0.1
0.2
0.3
0.4
0.5

22
0.6
0.7
0.8
0.9
MG1.5 (M1) and Styrene (M2)
Entry
M1
M2
m1
m2
1
2
3
4
5
9
2
1
1
1
1
1
1
2
9
0.67
0.207
0.123
0.07
0.019
0.2
0.2
0.2
0.2
0.2
Conversion
(%)
6.1
7.0
7.1
8.4
3.3
ML
9:1
2:1
1:1
1:2
1:9
20
15
10
r1
5
0
-5
-10
-15
-20
-0.6
-0.4
-0.2
0.0
0.2
r2
23
0.4
0.6
0.8
1.0
1.2
FR
Determination of r1
7
6
5
(F/f)(f-1)
4
3
2
1
0
Equation
y = a + b*x
Weight
No Weighting
Residual Sum
of Squares
0.00127
Pearson's r
0.99998
0.99996
Adj. R-Square
Value
-1
B
Intercept
B
Slope
Standard Error
-1.12407
0.01107
0.30745
0.00101
-2
0
5
10
15
20
25
2
F /f
Determination of r2
0
(f-1)/F
-2
-4
Equation
y = a + b*x
Weight
No Weighting
0.00334
Residual Sum
of Squares
-6
-0.99997
Pearson's r
0.99991
Adj. R-Square
Value
B
Intercept
B
Slope
Standard Error
0.28552
0.01816
-1.09657
0.00517
-8
-1
0
1
2
3
4
2
f/F
24
5
6
7
8
KT
0.4
0.2

0.0
-0.2
-0.4
Equation
y = a + b*x
Weight
No Weighting
Residual Sum
of Squares
0.00904
Pearson's r
0.98984
0.97305
Adj. R-Square
Value
B
Intercept
B
Slope
Standard Error
-0.63962
0.04716
0.98702
0.08184
-0.6
0.0
0.2
0.4
0.6

MG2 (M1) and Styrene (M2)
25
0.8
1.0
Entry
M1
M2
m1
m2
1
2
3
4
5
9
2
1
1
1
1
1
1
2
9
0.56
0.197
0.05
0.05
0.013
0.2
0.2
0.16
0.2
0.2
ML
9:1
2:1
1:1
1:2
1:9
r2
20
0
-20
-0.6
-0.4
-0.2
0.0
0.2
r1
FR
26
0.4
0.6
0.8
1.0
1.2
Conversion
(%)
2.9
1.6
4.1
2.1
4.1
Determination of r1
6
(F/f)(f-1)
4
2
0
Equation
y = a + b*x
Weight
No Weighting
2.02903
Residual Sum
of Squares
0.9762
Pearson's r
0.93728
Adj. R-Square
Value
-2
0
5
10
B
Intercept
B
Slope
15
20
Standard Error
-1.88924
0.44705
0.26501
0.03399
25
30
2
F /f
Determination of r2
0
(f-1)/F
-2
-4
-6
Equation
y = a + b*x
Weight
No Weighting
0.18642
Residual Sum
of Squares
Pearson's r
-0.9982
Adj. R-Square
0.99522
-8
Value
B
Intercept
B
Slope
Standard Error
0.15311
0.13577
-1.62907
0.05644
-10
0
1
2
3
2
f/F
KT
27
4
5
6
0.2

0.0
-0.2
-0.4
Equation
y = a + b*x
Weight
No Weighting
0.0596
Residual Sum
of Squares
0.93224
Pearson's r
0.82542
Adj. R-Square
Value
-0.6
0.0
0.2
0.4
0.6

28
B
Intercept
B
Slope
0.8
Standard Error
-0.70116
0.11736
0.82881
0.18573
1.0
1.2
Spectra
29
30
31