Supplementary Material
Star vs. Long Chain Branching of PLA with Multifunctional Aziridine
Liangliang Gu a, Yuewen Xu b,c, Grant W. Fahnhorst c, , Christopher W. Macosko a *
a
Department of Chemical Engineering and Materials Science, University of Minnesota, 421 Washington
Avenue SE, Minneapolis, Minnesota 55455
b
present address: Void Technologies, Neenah, WI 54956
c
Department of Chemistry, University of Minnesota, 07 Pleasant St SE, Minneapolis, MN 55455
Table S1 Molecular weight of Joncryl ADR4368 and PLA blended with TGIC and PMDA
Sample
code
TGIC
PMDA
PMDA
PMDA
wt. %
Mixing time
r
Mn (kg/mol)
Mw (kg/mol)
PDI
0.15
0.16
0.16
0.16
-
7
2
7
15
-
1.1
1.0
1.0
1.0
-
61
73
68
64
3.6
129
141
131
128
6.4
2.1
1.9
1.9
2.0
1.8
Joncryl
ADR4368
Molecular weight of PLA based on universal calibration described in Table 1 footnote. Molecular weight of Joncryl
based on PS standard since it is a styrene based polymer.
190
185
T (oC)
180
175
Neat PLA
0.16 wt.% PMDA
0.5 wt.% Joncryl
0.15 wt.% TGIC
0.25 wt.% TTMAP
170
165
Add branching agent
160
0
2
4
6
Time (min)
Figure S1 Representative temperature profiles during reactive processing. Time scale was shifted to make
the moment of adding branching agent time zero.
20
PT3
Torque (N m)
15
PT2
10
PT1
5
Add PMDA Add TTMAP
-2
0
2
Time (min)
Figure S2 Torque profiles for sample PT1, PT2 and PT3. Time scale was shifted to make the moment of
adding TTMAP time zero.
107
 (t, ) [Pa s]
106
Red: J
Blue: PT1
Purple: TP1
0.1 s
0.3 s
3s
10 s
5
10
-1
1s
-1
-1
-1
-1
3(t)
104
103
180°C
0.01
0.1
1
10
100
t [s]
Figure S3 Comparing extensional viscosity of sample J, TP1, TP1.
H, max
4
3
2
T1
T2
TP1
J
1
180°C
0.1
1
10
 [s ]
-1
Figure S4 Hencky strain at sample failure evaluated at Hencky strain of 2.7. For samples broken before εH
= 2.7, XE was calculated at εH,max.