Sample Name: Poly(styrene-b-ethylene oxide)
1H
NMR spectrum of the sample
Sample #: P3207-SEO
p3207-SEO
3.65 ppm
Structure:
CH2
CH
b
n
CH2
CH2
O
m
6.4 7.2 ppm
Composition:
Mn x 103
S-b-EO
51.0-11.5
PDI
1.05
2.36
1.0
Synthesis Procedure:
Poly(styrene-b-ethylene oxide) diblock copolymer is prepared
by living anionic polymerization.
SEC profile of the block copolymer
P3207-SEO
Characterization:
The molecular weight and polydispersity index (PDI) of the
block copolymer are characterized by size exclusion
chromatography (SEC).
The composition of the block
copolymer was calculated from 1H-NMR by comparing the
peak area of the phenyl polystyrene protons between 6.4 to 7.2
ppm and the ethylene oxide protons at 3.65 ppm.
Solubility:
The polymer is soluble in THF (at 35 °C), CHCl3, benzene,
toluene, dioxane. Low molecular weight SEO with high
contents of the polyethylene oxide block can also be solubilized
in methanol and water.
18
19
20
21
22
23
24
25
26
27
28
29
Ve (ml)
Size exclusion chromatography of poly(styrene-b-ethylene oxide)
Poly(styrene), Mn=51000, Mw=53500, PI=1.05
Block Copolymer PSt(51000)-b-PEO(11500), PI=1.05
Composition from H NMR
Thermal analysis of the sample# P3207-SEO
Thermal analysis results at a glance
Thermal analysis of the samples was carried out on a TA Q100
differential scanning calorimeter at a heating rate of
20oC/min.The midpoint of the slope change of the heat flow
plot of the second heating scan was considered as the glass
transition temperature (Tg).
For PS block Tg: 86oC
For PEO block
Tg: -61oC
Tm: 53oC
Tc: -32oC
Thermogram for the sample
Melting and crystallization curve for the PEO block
For PEO block:
The melting temperature (Tm) was taken as the maximum of the
endothermic peak where as the crystallization temperature (Tc)
was considered as the minimum of the exothermic peak.
-0.2
-0.3
-72.57°C
-0.4
-60.96°C(T)
-0.6
-55.72°C
-0.5
Heat Flow (W/g)
Heat Flow (W/g)
-0.4
-0.6
-0.8
-1.0
-0.7
-80
-75
-70
-65
-60
Exo Up
-55
-50
-45
-40
53.12°C
-1.2
Universal V4.2E TA Instruments
Temperature (°C)
For PS block
-1.4
20
30
40
50
Exo Up
60
70
80
Universal V4.2E TA Instruments
Temperature (°C)
0.70
0.8
-31.61°C
0.65
0.6
0.60
Heat Flow (W/g)
Heat Flow (W/g)
90.60°C
85.71°C(T)
72.72°C
0.55
0.4
0.50
50
Exo Up
60
70
80
Temperature (°C)
90
100
Universal V4.2E TA Instruments
0.2
-45
Exo Up
-40
-35
-30
Temperature (°C)
-25
-20
Universal V4.2E TA Instruments